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NorthGeorgiaWX

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  1. NorthGeorgiaWX

    Hurricane Michael

    By NorthGeorgiaWX,

    All data from the Atlanta NWS office
    Hurricane Michael Hits Georgia
     October 10, 2018
    [Overview]
    [Damaging Wind]
    [Wind Damage Photos]
    [Heavy Rainfall]
    [Tornadoes]

     
    Overview:
    Hurricane Michael made landfall along the Florida panhandle near Panama City on the afternoon of October 10, 2018 as a high-end Category 4 hurricane. Michael then moved rapidly inland, causing widespread wind damage along its path. Hurricane Michael was the strongest hurricane on record to make landfall along the Florida panhandle as well as the first major hurricane (Category 3+) to directly impact Georgia since the 1890s. In southwest Georgia, wind gusts as high as 115 mph were recorded in Donalsonville. Within the NWS Atlanta/Peachtree City county warning area, winds gusted over 70 mph in portions of central Georgia on the evening of October 10th, leading to widespread tree damage and power outages as well as severe crop damage, especially to cotton and pecan crops. Additionally, a few brief tornadoes in the outer bands of Michael caused sporadic damage in portions of the the area while heavy rainfall led to localized flooding. Michael quickly exited the state as a tropical storm on the morning of October 11th.
    For more information on the catastrophic damage experienced within the NWS Tallahassee area, click here.
    This infrared satellite image was taken as Hurricane Michael entered southwest Georgia as it maintained a Category 3 intensity on the evening of October 10, 2018. 
    (Click the map to enlarge it.)
     

    Damaging Winds:
    Within the portion of central Georgia in the NWS Atlanta/Peachtree City county warning area, sustained winds of 40-50 mph with gusts in the 60-75+ mph range downed countless trees and power lines. Numerous trees fell onto homes and businesses, causing additional damage. The peak wind gust officially recorded within the local warning area was in Arabi, GA where a 76 mph gust was recorded. Even stronger wind gusts well over hurricane force (74+ mph) were recorded in southwest Georgia in the NWS Tallahassee county warning area. Power outages lasted up to a week or even a bit longer for some areas. Below is a map displaying many of the strong wind gusts recorded across the state during Hurricane Michael. 
    Note: Wind gusts were likely stronger than displayed for a number of locations in central and south Georgia; however, recording instruments failed as electrical power and communications were lost.
    This map displays peak recorded wind gusts across Georgia during Michael.
    (Click the map to enlarge it.)
     
    This graph shows wind direction and wind speed/gusts in miles per hour in Eastman, GA. (Courtesy MesoWest, University of Utah)
    Gusts exceeded 60 mph before the instrument ceased reporting.
    Click the graph to enlarge it.
     
    This graph shows wind direction and wind speed/gusts in miles per hour in Dublin, GA. (Courtesy MesoWest, University of Utah)
    Wind gusts exceeded 60 mph before the instrument ceased reporting.
    Click the graph to enlarge it.
     
    This graph shows wind direction and wind speed/gusts in miles per hour in Cordele, GA. (Courtesy MesoWest, University of Utah)
    Wind gusts exceeded 50 mph before the instrument ceased reporting.
    Click the graph to enlarge it.

    Wind Damage Photos:

    Widespread tree damage of this magnitude occurred in Cordele. Many homes were damaged by falling trees. Electrical infrastructure experienced significant damage in many areas of central Georgia. (Cordele, GA)  
    Many large trees like this one were downed in Dodge County. (Courtesy WGXA-TV) Numerous trees and power lines were brought down in Americus. (Courtesy Americus Times-Recorder)
     
    Trees were downed around this house on Judy Lane in Americus. (Courtesy Americus Times-Recorder)



    Heavy Rainfall:
    Rainfall totals reached in excess of 5" in some locations. Though the ground was relatively dry due to recent dry weather, these rainfall totals led to isolated instances of flooding, including a few roads that were washed out. 
     
     
    This road near Dallas in Paulding County experienced a washout due to the heavy rainfall from Michael.
    (Courtesy: Paulding County Fire Department)


    Tornadoes:
    Three brief tornadoes touched down in the outer bands of Hurricane Michael on the evening of October 10th. See the specifics on these tornadoes below.
      1) Peach County Tornado: A brief EF-0 tornado snapped a few pine trees along Carver Drive, just south of Fort Valley State University.
    Damage Path - Peach County County Rating # of Injuries KML Peach EF-0 0    Rating: EF-0 Peak Wind: 75 MPH Path Length: 1.8 miles Path Width: 100 yards Fatalities: 0 Injuries: 0 Start Date: October 10, 2018 Start Time: 3:32 PM EDT Start Lat/Lon: 32.4955 / -83.8795 End Date: October 10, 2018 End Time: 3:36 PM EDT End Lat/Lon: 32.5195 / -83.8916     2) Crawford County Tornado: Hurricane Michael spawned a high-end EF-1 tornado in Crawford County within its outer rain bands. The tornado first touched down along Avera Road southwest of Roberta, snapping a few small trees and branches near a residence just east of the Hammett Road intersection. The tornado continued west-northwest, crossing Pope Road and Carroll Road, snapping and uprooting trees with the high-end EF-0 range. The tornado continued to move west where it intensified to a high end EF-1 with estimated maximum winds of 110 mph along Flint River Estates Road. Numerous trees were snapped from 10 to 20 feet off the ground or uprooted, including many hardwood trees. Several homes along the road were damaged by falling trees. A detached workshop at one of the homes was completely destroyed. The survey revealed that the garage was open with the opening facing the direction of the maximum winds, which led to its complete failure. The tornado continued westward, snapping trees as it crossed State Route 128 where it damaged another residence with falling trees. The tornado continued west, crossing Hortman Road, where a few small trees and large branches were downed before lifting as it approached Walker Chapel Road.
    Damage Path - Crawford County County Rating # of Injuries KML Crawford EF-1 0    Rating: EF-1 Peak Wind: 110 MPH Path Length: 5.0 miles Path Width: 250 yards Fatalities: 0 Injuries: 0 Start Date: October 10, 2018 Start Time: 3:58 PM EDT Start Lat/Lon: 32.6525 / -84.0267 End Date: October 10, 2018 End Time: 4:07 PM EDT End Lat/Lon: 32.6937 / -84.0974  
    Numerous trees were snapped or uprooted along the tornado track. This outbuilding was destroyed by the tornado. 3) Fulton County (Atlanta) Tornado: A brief tropical-cyclone tornado touched down just a couple miles southwest of downtown Atlanta along Dill Avenue SW. Along this road, several large trees were snapped. This is where a Tornado Debris Signature (TDS) was initially observed and where a peak wind of 75-80 mph was estimated. The tornado quickly crossed Highway 29 (Lee Street SW), downing several more trees along Avon Avenue SW between Princess Avenue SW and Wyland Drive SW. No further notable damage was seen downstream from this point.
    Damage Path - Fulton County County Rating # of Injuries KML Fulton EF-0 0    Rating: EF-0 Peak Wind: 80 MPH Path Length: 1.1 miles Path Width: 100 yards Fatalities: 0 Injuries: 0 Start Date: October 10, 2018 Start Time: 6:33 PM EDT Start Lat/Lon: 33.7179 / -84.4126 End Date: October 10, 2018 End Time: 6:37 PM EDT End Lat/Lon: 33.7236 / -84.4312  
    This large tree was downed by the tornado. This was one of several trees uprooted by the tornado.  
  2. NorthGeorgiaWX
    All data is from the National Weather Service in Atlanta
    North and Central Georgia
    October 2018 Climate Summary
    (Majority of locations were 3 to 4 degrees warmer than normal and ~1 inch wetter than normal)
    Monthly Top 10 Rankings:
    Athens 10th warmest on record Atlanta 6th warmest on record Macon 10th warmest on record *Complete rankings in tables below
     
    Hurricane Michael
    Hurricane Michael entered Georgia on 10/10 – 10/11 bringing 50 to 76+ mph wind gusts to portions of central GA. Listed below are a few of the highest measured gusts in our area. A map of the highest gusts across the state has also been included below. For more information on Hurricane Michael and the impacts in Georgia click here.
     Site
     Highest Gusts (mph) 
     Arabi – Crisp County
    76
     Cordele – Crisp County
    69
     Eastman – Dodge County
    63
     Hatley – Crisp County
    63
     Dublin – Laurens County
    61
     Louisville – Jefferson County 
    60
     McRae – Telfair County
    59
     Unadilla – Dooly County
    58
     Byromville – Dooly County
    58
    *Note: Data gathered from multiple sources including (ASOS/AWOS/GDOT/USFS/AEMN). Data slightly incomplete due to the failure of some observing sites.

     
    Temp. Extremes (°F) for October
     Site
    Warmest Temp.
    Coldest Temp.
     Athens
    95 (10/5)
    37 (10/22)
     Atlanta
    93 (10/6)
    43 (10/21)
     Columbus
    92 (10/5,10/6)
     44 (10/22,10/28) 
     Macon
    95 (10/5)
    36 (10/22)
     Cartersville
    92 (10/5)*
    32 (10/22)*
     DeKalb Peachtree Arpt 
    92 (10/5)*
    37 (10/22)
     Fulton Co. Arpt
    91 (10/5*,10/6*)
    36 (10/22)*
     Gainesville
    90 (10/5)*
    40 (10/22)*
     Peachtree City
     92 (10/5*,10/6*) 
    35 (10/22)
     Rome
    93 (10/5,10/6*)
    35 (10/22)
    * Set record for day
    October Averge Temperature (°F) and Rankings
    * Click on site name below to view a graph with additional data
    Site
     Avg. Temp and Current Ranking 
     Normal 
     Dep. from Normal 
    Record
    Athens
    66.3 (10th Warmest)
    63.0
    +3.3
    73.0 (1919)
    Atlanta
    67.4 (6th Warmest)
    63.3
    +4.1
    70.8 (1919)
    Columbus
    70.3 (11th Warmest)
    66.5
    +3.8
    77.5 (1919)
    Macon
    68.9 (10th Warmest)
    64.9
    +4.0
     74.4 (1919) 
    Cartersville
    64.2
    60.6
    +3.6
       DeKalb Peachtree Arp t
    65.7
    61.9
    +3.8
      Fulton Co. Arpt
    65.5
    62.5
    +3.0
      Gainesville
    64.8
    61.7
    +3.1
      Peachtree City
    66.3
    61.4
    +4.9
      Rome
    65.6
    61.1
    +4.5
       
    Precipitation Extremes (in) for October
    Site
      Highest Daily Amount  
    Athens
    1.87" (10/11)
    Atlanta
    3.42" (10/10)*
    Columbus
    3.26" (10/10)*
    Macon
    3.22" (10/10)*
    Cartersville
    2.90" (10/10)*
     DeKalb Peachtree Arpt  
    2.12" (10/10)*
    Fulton Co. Arpt
    4.34" (10/10)*
    Gainesville
    2.29" (10/10)*
    Peachtree City
    3.09" (10/10)*
    Rome
    1.02" (10/10)
    * Set record for day
    October Precipitation Totals (in) and Rankings
    * Click on site name below to view a graph with additional data
    Site
     Total Precip and Current Ranking 
     Normal 
     Dep. from Normal 
    Records
    Athens
    4.26" (39th Wettest)
    3.55"
    +0.71"
     11.23" (1937) 
    Atlanta
    4.75" (27th Wettest)
    3.41"
    +1.34"
    11.04" (1995)
    Columbus
    4.14" (28th Wettest)
    2.58"
    +1.56"
    8.41" (1995)
    Macon
    4.62" (19th Wettest)
    2.79"
    +1.83"
    9.39" (1959)
    Cartersville
    4.80"
    3.40"
    +1.40"
       DeKalb Peachtree Arpt 
    3.99"
    3.45"
    +0.54"
      Fulton Co. Arpt
    7.19"
    3.61"
    +3.58"
      Gainesville
    4.56"
    4.08"
    +0.48"
      Peachtree City
    4.79"
    3.41"
    +1.38"
      Rome
    3.60"
    3.86"
    -0.26"
       
    Records Set this October
    Athens: High Minimum Temperature - 71 on 10/10 (ties record of 71 in 2017) - 66 on 10/16 (breaks old record of 65 set in 1985) Atlanta: High Maximum Temperature - 91 on 10/4 (ties record of 91 in 1954) High Minimum Temperature - 71 on 10/7 (ties record of 71 in 2017) -  72 on 10/10 (ties record of 72 in 2017) Daily Precipitation Total - 3.42" on 10/10 (breaks old record of 1.59“ set in 1990) Columbus: High Minimum Temperature - 74 on 10/10 (ties record of 74 in 1919) Daily Precipitation Total - 3.26" on 10/10 (breaks old record of 1.11“ set in 1999) Macon: High Maximum Temperature - 92 on 10/16 (breaks old record of 88 set in 2015 and 1971) High Minimum Temperature  - 74 on 10/10 (breaks old record of 72 set in 2017) Daily Precipitation Total - 3.22" on 10/10 (breaks old record of 1.18“ set in 1994)  
    Yearly Temperatures at DaculaWeather.com

     
  5. NorthGeorgiaWX
    One of the winters that is an analog for the Weatherbell forecast is the winter of 2009-2010. Since you probably don't remember many of the details, I've brought many of them together here for you to read.  My next post will be another analog, 2002-2003. 

    The average temperatures for the December 2009 - February 2010 period were among some of the coldest ever across north and central Georgia.  Each of the four climate sites - Atlanta Hartsfield-Jackson International Airport, Athens Ben Epps Airport, Columbus Metropolitan  Airport, and Macon/Middle Georgia Regional Airport - saw average temperatures among the ten coldest ever recorded.  The average temperatures for Columbus had the 4th coldest average temperature for the winter season, while Macon tied for the 5th coldest, Atlanta was the eighth coldest and Athens tied for the ninth coldest winter season.
     
    Dec - Feb 2009-2010
     

    Dec 2009 Temp Anomalies
     

    Jan 2010 Temp Anomalies
     

    Feb 2010 Temp Anomalies
     

    DJF 500 mb Anomalies Winter 2009-2010

    The total snowfall this season at Atlanta breaks top 5 for total snowfall recorded December through March for the period of record.  As of midnight Wednesday March 3, the total snowfall for the winter season was 5.3 inches which is now the fifth highest since accurate snow records began in 1929. Additionally... the snow on March 2nd marks the third time measurable snow and the tenth time at least a trace of snow or sleet fell at Atlanta Hartsfield-Jackson International Airport this season. In an average winter season Atlanta typically experiences 4 days of measurable snow and 6 days with a trace or more of snow or sleet.

     
    A few of my own pictures...


     
    January 7th, 2010 - Snow

    On Thursday, January 7th, a cold front pushed across north and central Georgia, with the combination and timing of cold air and moisture bringing wintry precipitation across the area. Light snow began during the late morning hours. Snow fell across the area through the day and into the early hours of Friday January 8th.  The reinforcing cold air behind the front remained across much of the area through the weekend.  North and much of central Georgia's temperatures stayed at or below freezing through Sunday.  The map to the left shows the snowfall amounts across north and central Georgia.

    March 2, 2010  Snow

    An upper level disturbance traversing the western portion of the United States February 28 and March 1, 2010  helped to develop a surface low along the Texas coast on March 1. This surface low pressure system tracked along the Gulf coast and advected moisture ahead of the system into Georgia from both the Gulf of Mexico and the Atlantic Ocean. By Tuesday, March 2, the surface low moved across southern Georgia and the Florida panhandle  and by that afternoon, had moved into the Atlantic Ocean along the Carolina coast. This system brought both rain and snow to the state. Precipitation started as rain and began moving into western Georgia just before midnight on March 2. During the morning hours on March 2 the precipitation continued moving across the state and changed to snow across north Georgia. The snow proceeded to change back to rain during the afternoon and ended across eastern Georgia late in the evening. Snowfall amounts averaged from 2 to 4 inches across north Georgia. However, higher values were reported across northeast Georgia with reports of 9.0 inches in Union county.
     
    February 12th, 2010 Snow

    On Friday, February 12th, precipitation associated with a surface low tracking across the Gulf of Mexico and an upper level short wave tracked across much of north and central Georgia. Light snow began over portions of west Georgia around noontime, then spread eastward through the afternoon before tapering off to flurries by mid evening and dissipating by early Saturday morning.  Snow and slush on the roadways froze overnight leading to hazardous driving conditions late Friday night into Saturday morning.  The map to the left shows the snowfall amounts across north and central Georgia.
     
    National Climatic Data Center - Click here for full review of the Winter of 2009-2010
     
    The purpose of this special report is to provide documentation, data analysis, and a preliminary understanding of large-scale climate patterns and their effects on regional weather events. In climatological terms, the Cold Season lasts from October through March. The 2009/2010 Cold Season for North America was historically active and powerful. Extreme fluctuations in temperature and precipitation in the mid-latitudes during this period can be attributed to a wide variety of rapidly progressing weather systems. The persistent systems were influenced by larger scale patterns. The strong warm phase of the El Niño–Southern Oscillation (ENSO) helped to alleviate moderate to exceptional drought across the contiguous United States. Meanwhile, the record-setting negative phase of the Arctic Oscillation produced record cold temperatures in the Deep South. During the October–March period, the contiguous U.S. experienced its eighth wettest such period, while the average temperature was below average (36th coolest). The anomalously cold air, coupled with copious amounts of moisture produced historical snowfall amounts that bested monthly and seasonal records across the country. While the overall drought footprint was at its lowest in the last decade, the moisture surplus caused flooding in the Upper Midwest and New England. High amplitude flow patterns helped the cold arctic air remain entrenched for days and weeks, devastating mild climate crops. The extreme winter of 1977/1978 was similar, as a moderate warm phase of ENSO coincided with a strong negative phase of the Arctic Oscillation. The effects of large-scale climate patterns are often influential on regional weather events and when they are extreme and historic in nature, their local effects are profound and far reaching. 
    The snow cover extent for the contiguous U.S. during the 2009/2010 Cold Season was above average for the season as a whole, but there was significant variation from month to month. The snowy season got off to an early start with several storms impacting the U.S. during October. These storms helped produce the largest average snow extent during any October for the contiguous U.S. in the 42 year satellite record, according to Rutger's University Global Snow Lab. Conversely, November was very quiet with much below average snow cover. The following three months were cold and snowy with the extent being much above average for December (all time snowiest), January (6th snowiest), and February (3rd snowiest). During January, snow and freezing temperatures were reported as far south as central Florida. 



  6. NorthGeorgiaWX
    The upcoming 5 days are going to really make you feel like it's fall!
    Today, sunny and warm! Awesome day to get outside, and probably the best day to do so through Monday.
    I'll share several images here, temps and temp anomalies for Thu/Fri, and precip through Sunday night.
    Max Temp Thursday

     
    Thursday Max Temp Anomalies

     
    Max Temps Friday

     
    Friday Max Temp Anomalies - Notice that some of those temps are close to 20 degrees below normal. Looks like a wedge. A wedge is also called Cold Air Damming or CAD. 

     
    Precip through Sunday - For most, close to an inch of rain will fall

  9. NorthGeorgiaWX
    A daily summary of social media discussions about the weather.Early start to winter there...Click on the link in the Tweet below. Awesome fall images.Very interesting story of an event from October 1844'tis the season! :-) Some areas are going from fall to winter already!Garth Brooks concert at Notre Dame StadiumView the full article
  10. NorthGeorgiaWX
    A daily summary of social media discussions about the weather. Early start to winter there... Click on the link in the Tweet below. Awesome fall images. Very interesting story of an event from October 1844 'tis the season! :-) Some areas are going from fall to winter already! Garth Brooks concert at Notre Dame Stadium
    View the full article
  13. NorthGeorgiaWX
    Temp Anomalies for SundayWell, at least I have a few alternatives for posting information. Starting today I will be making these consolidated "daily" post. They will contain everything that I would normally share in a day, all rolled up into one post. Who knows, it may be easier for you to read instead of wading through multiple post. But this will mean that you will have to come back here to get the updates. I can post a comment on FB when I do an update, but that's about it. 

    This consolidated post will be ordered with the most recent update at the bottom and I will time stamp each update for you.  All I ask is that if you like the post, to please click on the Facebook button at the bottom to "Like" it. Since the Facebook page isn't working, new followers will be harder to come by, so those likes will go a long way in helping me out.  Thursday, 8:33 am
    If it doesn't feel like fall for you yet, it will very soon.  It's looking like our high temps will be below normal for about a week. With rain coming in on Saturday, we'll see a little bump up, but still below normal. The six images below are the high temperature anomalies through Wednesday, and as you can see, we will finally get a week of BELOW normal temps instead of above.  Friday Saturday Saturday Monday Tuesday Wednesday Thursday, 9:05 am
    Blocking events are what helps to push the cold air south. And speaking of cold air, the very NW corner on NC and NE corner of TN could see a flake or two of snow. Fun times ahead! :-) Thursday, 10:12 am
    Here's another story on the crop losses in Georgia due to Hurricane Michael, and the losses are estimated to be  in the neighborhood of 3 billion dollars.

    https://www.ajc.com/news/hurricane-michael-damage-billion-georgia-agricultural-losses/TLLCf5XpCsnJvMAhWZE8cI/
    Thursday, 11:26 am
    Thursday, 12:13 pm
    Animated GIF showing the 10 day temperature anomalies from the 00Z Euro operational run. Thursday, 1:43 pm
    Here's the Weekly Weather Briefing from the Atlanta NWS office. Thursday, 2:48 pm
    Whoa!!!
    View the full article
  15. NorthGeorgiaWX
    Today in Weather History
    for March 22 

    March 22, 1920 
    A spectacular display of the Northern Lights was visible as far south as Bradenton FL, El Paso TX, and Fresno CA. At Detroit MI, the display was described so brilliant as to blot out all stars below first magnitude. (22nd-23rd) (The Weather Channel) 

    March 22, 1936 
    A great flood crested on rivers from Ohio to Maine. The flood claimed 107 lives and caused 270 million dollars property damage. (David Ludlum) 

    March 22, 1954 
    Six to ten inch rains caused the Chicago River to overflow its banks. (The Weather Channel) 

    March 22, 1987 
    An intense storm produced heavy snow in the southern and central Rockies, and high winds from southern California to West Texas. Wolf Creek Pass CO received 24 inches of snow, and winds gusted to 69 mph at Ruidoso NM. Blizzard conditions were reported in eastern Colorado. (The National Weather Summary) (Storm Data) 

    March 22, 1988 
    Rain and high winds battered the Northern Pacific Coast Region, with wind gusts to 78 mph at Ocean Shores WA. The high winds uprooted trees and down power lines. Ten cities in the northeastern U.S. reported new record low temperatures for the date. Eight cities in the central U.S. reported record highs. Southerly winds gusting to 60 mph helped push the mercury at Ottumwa IA to a record warm reading of 83 degrees. (Storm Data) (The National Weather Summary) 

    March 22, 1989 
    Six cities in the Great Lakes Region, and three in southern Texas, reported new record low temperatures for the date, including Alpena MI with a reading of 9 above zero, and Brownsville TX with a reading of 38 degrees. (The National Weather Summary) 

    March 22, 1990 
    A surge of arctic air kept temperatures in the teens and 20's during the day in the north central U.S., and heavy snow fell over parts of Montana. Record warmth was reported in the western U.S.,and in Alaska. Phoenix AZ reported a record high of 94 degrees, and the town of Barrow, located along the arctic coast of Alaska, reported a record high of 20 degrees. (The National Weather Summary) 

    Data courtesy of WeatherForYou              
    View the full article
     
  16. NorthGeorgiaWX
    Weather History
    For Saturday, April 20, 2019

    1901 - A spring storm produced unusually heavy snow in northeast Ohio. Warren received 35.5 inches in thirty-six hours, and 28 inches fell at Green Hill. Akron OH established April records of 15.6 inches in 24 hours, and 26.6 inches for the month. Pittsburgh PA established April records of 12.7 inches in 24 hours, and 13.5 inches for the month. (David Ludlum) (The Weather Channel)

    1920 - Tornadoes in Mississippi and Alabama killed 219 persons. (David Ludlum)

    1952 - The tankers Esso Suez and Esso Greensboro crashed in a thick fog off the coast of Morgan City LA. Only five of the Greensboro's crew survived after the ship bursts into flame. (David Ludlum)

    1987 - Fifty-two cities in the central and eastern U.S. reported new record high temperatures for the date. The high of 92 degrees at Memphis TN was a record for April, and the high of 94 at Little Rock AR equaled their April record. (The National Weather Summary)

    1988 - A storm in the western U.S. brought heavy rain to parts of California. Mount Wilson was soaked with 4.15 inches of rain in 24 hours. The heavy rain caused some flooding and mudslides in the Los Angeles area, and a chain reaction collision of vehicles along the Pomona Freeway which resulted in 26 injuries. (Storm Data) (The National Weather Summary)

    1989 - Hot weather spread from the southwestern U.S. into the Great Plains Region. Twenty-three cities reported new record high temperatures for the date. The afternoon high of 104 degrees at Tucson AZ was an April record, and highs of 87 at Provo UT, 90 at Pueblo CO, and 85 at Salt Lake City UT, equaled April records. (The National Weather Summary)

    1990 - A fast moving Pacific storm produced heavy snow in the central mountains and the Upper Arkansas Valley of Colorado, with a foot of snow reported at Leadville. Thunderstorms in the south central U.S. produced wind gusts to 76 mph at Tulsa OK, and heavy rain which caused flooding of Cat Claw Creek in the Abilene TX area. Lightning struck the building housing a fish farm in Scott AR killing 10,000 pounds of fish. Many of the fish died from the heat of the fire. (The National Weather Summary) (Storm Data)

    2006 - Up to five feet of snow falls in the Dakotas. I-94 and other highways were closed, power was out for thousands and caused at least four deaths.

    Data courtesy of WeatherForYou              
    View the full article
     
  17. NorthGeorgiaWX
    Today in Weather History
    for May 15 

    May 15, 1834 
    The Northern Atlantic Coast States were in the midst of their greatest May snowstorm of record. The hills around Newbury, VT, were covered with two to three feet of snow. (David Ludlum) 

    May 15, 1968 
    A tornado touched down southwest of Anchorage, AK. It was the second of just three tornadoes reported in Alaska since 1950. (The Weather Channel) 

    May 15, 1972 
    The worst ice jam flooding of memory for long-time residents took place along the Kuskokwim River and Yukon River in Alaska. It was the first time since 1890 that the two rivers "flowed as one". The towns of Oscarville and Napaskiak were completely inundated. (15th-31st) (The Weather Channel) 

    May 15, 1987 
    Unseasonably warm weather returned to the north central U.S. Seven cities reported record high temperatures for the date, including Janestown, ND, with a reading of 96 degrees. Thunderstorms in Utah produced five inches of rain south of Bicknell. (The National Weather Summary) (Storm Data) 

    May 15, 1988 
    Thunderstorms in Oklahoma produced wind gusts to 80 mph in Oklahoma County, and baseball size hail at Pawnee. Hail piled up to a depth of 18 inches south of Pawnee. Hail damage in Oklahoma was estimated at close to 25 million dollars. Thunderstorms in the Upper Midwest produced golf ball size hail around Cleveland, OH, and wind gusts to 83 mph at Angola, IN. (Storm Data) (The National Weather Summary) 

    May 15, 1989 
    Thunderstorms developing along and north of a stationary front produced severe weather in the south central U.S. Thunderstorms spawned eleven tornadoes, and there were 145 reports of large hail and damaging winds. Softball size hail caused 2.1 million dollars damage at Sherman, TX. (The National Weather Summary) (Storm Data) 

    May 15, 1990 
    Thunderstorms produced severe weather from the Central Plains Region and Oklahoma to Indiana and western Kentucky. Thunderstorms spawned fifteen tornadoes, including seven in Oklahoma, and there were 165 reports of large hail or damaging winds. A tornado killed one person, injured a dozen others, and caused four million dollars damage at Stillwater, OK. Another tornado injured eight persons at Foyil, OK. Thunderstorms in Oklahoma also produced wind gusts to 92 mph at Oologah Lake, and softball size hail at Canton and north of Oakwood. (The National Weather Summary) (Storm Data) 

    Data courtesy of WeatherForYou              
    View the full article
     
  18. NorthGeorgiaWX
    Today in Weather History
    for August 21 

    August 21, 1883 
    A tornado hit Rochester, MN, killing 31 persons and wrecking 1351 dwellings. (David Ludlum) 

    August 21, 1888 
    A tornado swarm occurred in Maryland and Delaware. Many waterspouts were seen over Chesapeake Bay. (Sandra and TI Richard Sanders - 1987) 

    August 21, 1918 
    A tornado struck Tyler, MN, killing 36 persons and destroying most of the business section of the town resulting in a million dollars damage. (David Ludlum) 

    August 21, 1983 
    The temperature at Fayetteville, NC, soared to 110 degrees to establish a state record. (The Weather Channel) 

    August 21, 1987 
    Early morning thunderstorms produced severe weather in eastern Iowa and west central Illinois. Thunderstorms produced wind gusts to 82 mph at Moline IL, and tennis ball size hail at Independence IA. Rock Island IL was drenched with 3.70 inches of rain. Total damage for the seven county area of west central Illinois was estimated at twelve million dollars. (National Weather Summary) (Storm Data) 

    August 21, 1988 
    Thunderstorms spawned several tornadoes in Iowa, produced wind gusts to 63 mph in the Council Bluffs area, and drenched Sioux Center IA with up to 6.61 inches of rain. (Storm Data) (The National Weather Summary) 

    August 21, 1989 
    Afternoon and evening thunderstorms produced severe weather from Kansas to Minnesota and North Dakota. Thunderstorms in Minnesota produced baseball size hail from Correll to north of Appleton. Thunderstorms in north central Kansas produced wind gusts higher than 100 mph at Wilson Dam. Thunderstorms around Lincoln NE produced baseball size hail and up to five inches of rain, and Boone NE was deluged with five inches of rain in an hour and a half. (The National Weather Summary) (Storm Data) 

    Data courtesy of WeatherForYou
    View the full article
  19. NorthGeorgiaWX
    I'll try to be quiet while you sleep.... it's 3:28 am here in Atlanta, do you know where your cars are? 🙂
    There are some light showers moving into the Lincoln area right now and they may linger through the early morning hours, bu most of the day should be dry. 

     
    Recording #147.mp4  
     
    Here's the hour by hour

     
    Here are the expected temperature anomalies (GFS) through the end of next week. Sun-Tue will be warm, but great after that. 

     
    Annnnd the forecast. I'll tell you what... after today, you won't need me to help you with the weather. 🙂 It will be great to have a dry and relatively cool Nationals. 

     
    Hope everyone has a great day!
     
  20. NorthGeorgiaWX
    The main focus on this article is not to make a winter forecast, but  to explore what effects El Nino's and teleconnections have on winter weather across the southeast. One of the main sources of data in this report comes from a weather friend of mine that I call "Brother Larry". Larry would prefer to remain anonymous, so from here on out you'll hear me refer to Larry as "Brother Larry". :-)  Larry has a wealth of information about the weather history in Georgia, and I'll be using a lot of his findings to help give you an idea how this winter may turn out, based on the environment created by the El Nino, as well as several other factors. Again, this data is based on analog years, or those years that most closely identify with the current patterns, so keep that in mind. Analog's are not perfect, but they do give us a very good idea about how things have happened in the past and how they may happen again in the future. 

    Again, almost all of the text below (other than a few of my own edits and additions) is from Larry, and he gets all the credit for the research and stats. ​ ENSO and Southeast US  Winters
    This data was compiled by taking a list of 26 “cold” US winters (Dec/Jan/Feb) since 1894 -1895 (i.e., the coldest 23%) for the eastern third of the US. This requires solid, widespread, below normal anomalies, and requires the southeast to be pretty chilly itself. The two maps to the right were created with data from the list of years below, but that dataset only goes back to 1948, so the maps I'm displaying are not 100% complete with the years in the list. Here's the list of those winters, and you can see the years I used on the maps themselves. 
    Also, Larry's 26 coldest winters study was done the better part of 10 years back, since then, it is possible that some of 09, 10, 13, 14, etc. could be added, although he is not reassessing those now. 2002 - 2003 1995 - 1996 1993 - 1994 1981 - 1982 1980 - 1981 1978 - 1979 1977 - 1978 1976 - 1977 1969 - 1970 1968 - 1969 1967 - 1968 1963 - 1964 1962 - 1963 1960 - 1961 1947 - 1948 1939 - 1940 1935 - 1936 1917 - 1918 1911 - 1912 1909 - 1910 1904 - 1905 1903 - 1904 1901 - 1902 1900 - 1901 1898 - 1899 1894 - 1895 Temperature Anomalies Precipitation Nino Base State
    ENSO Regions ONI Chart from Golden Gate Weather Services - http://ggweather.com/enso/oni.png Forecast So now that we have our list of base years, let's look at the base Nino state for those winters. Before we can do that, we need to take a look at the various Nino/Nina classifications. Graphs and Charts

    The Oceanic Niño Index (ONI) has become the standard that NOAA uses for identifying El Niño (warm) and La Niña (cool) events in the tropical Pacific.  The ONI is defined as the running 3-month mean SST anomaly for the Niño 3.4 region (i.e., 50N-50S, 120W-170W).  Events are defined as 5 consecutive overlapping 3-month periods at or above the +0.5 anomaly for warm (El Niño) events and at or below the -0.5 anomaly for cold (La Niña) events.  The threshold is further broken down into: Weak (with a 0.5 to 0.9 SST anomaly) Moderate (1.0 to 1.4) Strong (1.5 to 1.9) Very Strong (≥ 2.0)  For the purpose of this blog post, for an event to be categorized as weak, moderate, strong or very strong, it must have equaled or exceeded the threshold for at least 3 consecutive overlapping 3-month periods. Here's an analysis of the 26 cold winters by ENSO state: Strong Nino: 0 of 26 (0%) Moderate Nino: 1 of 26 (4%) Weak Nino: 9 of 26 (35%) Neutral positive: 4 of 26 (15%) Neutral negative: 5 of 26 (19%) Weak Nina: 6 of 26 (23%) Moderate Nina: 1 of 26 (4%) Strong Nina: 0 of 26 (0%) Dec-Feb temperature anomalies during weak Nino's Notice that out of all the cold years, the majority of them occurred during weak Nino's (35%). Also notice that out of all of those cold winters, none of them occurred with a strong Nino or a strong Nina. 

    The map on the left depicts the temperature anomalies that occurred during a Weak Nino. Due to the data only going back to 1948, all of the years are not depicted, but this will give you a good idea. 

    As you can see, a weak Nino is what we'd like to see come Dec-Feb. If the current one stays too strong, it could severely limit our cold this winter based on past analogs. keep in mind, Larry's study is based on temperatures, not precipitation.  ​ ​Nino and the Pacific Decadal Oscillation (PDO)
    +PDO or Warm State -PDO or Cold State PDO Index (http://www.daculaweather.com/4_pdo_index.php) While it's easy to look at one specific weather pattern, there are many factors that determine how a winter will turn out, with the ENSO state being just one of those. But there are other teleconnections and long term patterns that also have an effect on our winter weather, and they all work in tandem with each other.  Graphs and Charts

    Now we are going to turn our attention to the PDO state or Pacific Decadal Oscillation. First, the definition from the National Center for Environmental Information:

    "The Pacific Decadal Oscillation (PDO) is often described as a long-lived El Niño-like pattern of Pacific climate variability (Zhang et al. 1997). As seen with the better-known El Niño/Southern Oscillation (ENSO), extremes in the PDO pattern are marked by widespread variations in the Pacific Basin and the North American climate. In parallel with the ENSO phenomenon, the extreme phases of the PDO have been classified as being either warm or cool, as defined by ocean temperature anomalies in the northeast and tropical Pacific Ocean. When SSTs are anomalously cool in the interior North Pacific and warm along the Pacific Coast, and when sea level pressures are below average over the North Pacific, the PDO has a positive value. When the climate anomaly patterns are reversed, with warm SST anomalies in the interior and cool SST anomalies along the North American coast, or above average sea level pressures over the North Pacific, the PDO has a negative value (Courtesy of Mantua, 1999). " 

    Here's an analysis of the cold 26 winters by DJF averaged PDO status:+ PDO: 18 of 58 (31%) - PDO: 8 of 57 (14%) Again, much as it was with weak Nino's, many of our coldest winters occurred during a + PDO state, while only 8 out of 57 occurred during a negative PDO state. ​ Nino and the North Atlantic Oscillation (NAO)
    In order for us to get long lasting cold air that stays locked in, we need some blocking. There are several teleconnection patterns that aid in developing this blocking, one of which is the North Atlantic Oscillation or NAO. Graphs and Charts
    Negative NAO (-NAO) Positive NAO (+NAO) Here's the definition of the NAO:
    "The North Atlantic Oscillation (NAO) is a climatic phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high. Through fluctuations in the strength of the Icelandic low and the Azores high, it controls the strength and direction of westerly winds and storm tracks across the North Atlantic. It is part of the Arctic Oscillation, and varies over time with no particular periodicity."
    Strong positive phases of the NAO tend to be associated with above-average temperatures in the eastern United States and across northern Europe and below-average temperatures in Greenland and oftentimes across southern Europe and the Middle East. They are also associated with above-average precipitation over northern Europe and Scandinavia in winter, and below-average precipitation over southern and central Europe. Opposite patterns of temperature and precipitation anomalies are typically observed during strong negative phases of the NAO. For us, negative is what we're looking for in the winter. 

    Let's take a look at the analysis of the cold 26 Dec-Feb winters by averaged NAO status:

    – NAO: 19 of 48 (40%) + NAO: 7 of 67 (10%) Again, a large number of the cold winters had a negative NAO. ​​ Piecing It All Together...
    Now let's take the combination of the ENSO state (in our case, Nino), and factor in the PDO and NAO and let's see what we get. Here's the analysis of the 26 cold winters by a combination of Dec-Feb averaged PDO and NAO status:+ PDO/-NAO: 12 of 25 (46%) - PDO/-NAO: 7 of 23 (30%) (all 7 had (PDO – NAO) > 0) + PDO/+NAO: 6 of 33 (18%) - PDO/+NAO: 1 of 34 (3%) Things start to change a little. Obviously, the combination of +PDO and -NAO are the best combination, and that makes perfect sense. During the positive phase of the PDO, the wintertime Aleutian low is deepened and shifted southward, warm/humid air is advected along the North American west coast and temperatures are higher than usual from the Pacific Northwest to Alaska but below normal in Mexico and the southeastern United States. Add the effects of the blocking provided by the NAO and you lock in the cold air instead of having it rush out to sea.  Now, let's really lay it out.
    Here's "Brother Larry's" analysis of the 26 cold winters by a combination of ENSO state and Dec-Feb averaged PDO and NAO status:

    Strong Nino:+PDO/-NAO: 0 of 6 (0%) -PDO/-NAO: 0 of 1 (0%) +PDO/+NAO: 0 of 7 (0%) -PDO/+NAO: 0 of 1 (0%)
    Moderate Nino:+PDO/-NAO: 1 of 2 (50%) -PDO/-NAO: 0 of 0 (N/A) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 0 of 2 (0%)
    Weak Nino:+PDO/-NAO: 6 of 7 (86%) -PDO/-NAO: 2 of 2 (100%) +PDO/+NAO: 1 of 2 (50%) -PDO/+NAO: 0 of 4 (0%)
    Neutral Positive:+PDO/-NAO: 2 of 4 (50%) -PDO/-NAO: 0 of 3 (0%) +PDO/+NAO: 2 of 10 (20%) -PDO/+NAO: 0 of 5 (0%)
    Neutral Negative:+PDO/-NAO: 1 of 3 (33%) -PDO/-NAO: 2 of 7 (29%) +PDO/+NAO: 2 of 10 (20%) -PDO/+NAO: 0 of 5 (0%)
    Weak Nina:+PDO/-NAO: 2 of 2 (100%) -PDO/-NAO: 3 of 5 (60%) +PDO/+NAO: 1 of 4 (25%) -PDO/+NAO: 0 of 7 (0%)
    Moderate Nina:+PDO/-NAO: 0 of 1 (0%) -PDO/-NAO: 0 of 3 (0%) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 1 of 4 (25%)
    Strong Nina:+PDO/-NAO: 0 of 0 (N/A) -PDO/-NAO: 0 of 2 (0%) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 0 of 6 (0%) Conclusions...
    Weak Nino’s give the highest percentage chance for cold of any of the ENSO states by far (with weak Nina’s second); however, a combo of -PDO/+NAO seems to make it difficult even for weak Nino’s. A very impressive 13 of 16 (81%) of the aggregate of weak Nino's and weak Nina's with -NAO were cold. Don't ever bet on cold with either a strong Nino or a strong Nina since none of the 23 were cold. +PDO about doubles the percent chance for cold versus a -PDO. A -NAO more than doubles the percentage chance for cold versus a +NAO and a somewhat higher chance than a +PDO gives. So, I give small edge to –NAO over a +PDO regarding cold prospects. Regardless, both are very important. A +PDO/-NAO combo gives close to twice the percentage chance for cold versus the percentage chance for all PDO/NAO combos in the aggregate. A -PDO/-NAO is the next best combo for cold prospects, but mainly if NAO is more negative than PDO. Don't ever bet on cold with a combination of -PDO/+NAO, since only 1 out of 34 were cold. If there is a +PDO, the chances for a –NAO appear to be high for only weak to moderate Nino’s. The chances appear to only be about 50-50 for strong Nino’s. For neutral ENSO, the chances seem to be surprisingly low (partial negative correlation suggested). The best shot at a +PDO/-NAO combo appears to be with a weak to moderate Nino's. On the other hand, only 3 of 34 (9%) Nina’s had a +PDO/-NAO. A pretty high 17 of 34 (50%) Nina’s had a –PDO/+NAO. A +PDO is difficult with a moderate to strong Nina. Only one out of 16 (6%) had one. A –PDO seems rather difficult with a strong Nino, only 2 out of 15 (13%) had one. +PDO and –PDO winters are about evenly split. But +NAO winters have been a bit more common than -NAO in long term: 58% vs. 42%. Winter Precipitation
    Regarding wintry precipitation for Atlanta, when looking at the three standalone super Nino's (1972-1973, 1982 -1983, 1997-1998) as well as the six strong to super strong 2nd year Nino's (1877-1888, 1888-1889, 1896-1887, 1905-1906, 1940-1941, 1987-1988), Atlanta more often than not, had one major winter storm, but not always:1877-1888: 2.5" 1/3/1878 & a non-major freezing rain followed on 1/9/1878 1888-1889: 6" 2/21/1889 1896-1967: 6.2" 12/2/1896 1905-1906: 6.2" for the season including 3.5"+ major 1/26/1906, measurable snow D, J, and F 1940 -1941: only T of snow 1972 -1973: historic ZR 1/7-8/1973, which included 1" mainly ice pellets; (also, historic snow hit central GA in Feb though Atlanta missed that one) 1982 -1983: 10.3" S/IP for season including 7.9" 3/24/1983 (heaviest since 1940) and measurable snow J, F, and M 1987- 1988: 4.2" of mainly IP 1/7/1988 (would have been ~8" if all snow) 1997- 1998: only 0.6" 12/29/1997 View the full article
  21. NorthGeorgiaWX
    The main focus on this article is not to make a winter forecast, but  to explore what effects El Nino's and teleconnections have on winter weather across the southeast. One of the main sources of data in this report comes from a weather friend of mine that I call "Brother Larry". Larry would prefer to remain anonymous, so from here on out you'll hear me refer to Larry as "Brother Larry". :-)  Larry has a wealth of information about the weather history in Georgia, and I'll be using a lot of his findings to help give you an idea how this winter may turn out, based on the environment created by the El Nino, as well as several other factors. Again, this data is based on analog years, or those years that most closely identify with the current patterns, so keep that in mind. Analog's are not perfect, but they do give us a very good idea about how things have happened in the past and how they may happen again in the future. 

    Again, almost all of the text below (other than a few of my own edits and additions) is from Larry, and he gets all the credit for the research and stats. ​ ENSO and Southeast US  Winters
    This data was compiled by taking a list of 26 “cold” US winters (Dec/Jan/Feb) since 1894 -1895 (i.e., the coldest 23%) for the eastern third of the US. This requires solid, widespread, below normal anomalies, and requires the southeast to be pretty chilly itself. The two maps to the right were created with data from the list of years below, but that dataset only goes back to 1948, so the maps I'm displaying are not 100% complete with the years in the list. Here's the list of those winters, and you can see the years I used on the maps themselves. 
    Also, Larry's 26 coldest winters study was done the better part of 10 years back, since then, it is possible that some of 09, 10, 13, 14, etc. could be added, although he is not reassessing those now. 2002 - 2003 1995 - 1996 1993 - 1994 1981 - 1982 1980 - 1981 1978 - 1979 1977 - 1978 1976 - 1977 1969 - 1970 1968 - 1969 1967 - 1968 1963 - 1964 1962 - 1963 1960 - 1961 1947 - 1948 1939 - 1940 1935 - 1936 1917 - 1918 1911 - 1912 1909 - 1910 1904 - 1905 1903 - 1904 1901 - 1902 1900 - 1901 1898 - 1899 1894 - 1895 Temperature Anomalies Precipitation Nino Base State
    ENSO Regions ONI Chart from Golden Gate Weather Services - http://ggweather.com/enso/oni.png Forecast So now that we have our list of base years, let's look at the base Nino state for those winters. Before we can do that, we need to take a look at the various Nino/Nina classifications. Graphs and Charts

    The Oceanic Niño Index (ONI) has become the standard that NOAA uses for identifying El Niño (warm) and La Niña (cool) events in the tropical Pacific.  The ONI is defined as the running 3-month mean SST anomaly for the Niño 3.4 region (i.e., 50N-50S, 120W-170W).  Events are defined as 5 consecutive overlapping 3-month periods at or above the +0.5 anomaly for warm (El Niño) events and at or below the -0.5 anomaly for cold (La Niña) events.  The threshold is further broken down into: Weak (with a 0.5 to 0.9 SST anomaly) Moderate (1.0 to 1.4) Strong (1.5 to 1.9) Very Strong (≥ 2.0)  For the purpose of this blog post, for an event to be categorized as weak, moderate, strong or very strong, it must have equaled or exceeded the threshold for at least 3 consecutive overlapping 3-month periods. Here's an analysis of the 26 cold winters by ENSO state: Strong Nino: 0 of 26 (0%) Moderate Nino: 1 of 26 (4%) Weak Nino: 9 of 26 (35%) Neutral positive: 4 of 26 (15%) Neutral negative: 5 of 26 (19%) Weak Nina: 6 of 26 (23%) Moderate Nina: 1 of 26 (4%) Strong Nina: 0 of 26 (0%) Dec-Feb temperature anomalies during weak Nino's Notice that out of all the cold years, the majority of them occurred during weak Nino's (35%). Also notice that out of all of those cold winters, none of them occurred with a strong Nino or a strong Nina. 

    The map on the left depicts the temperature anomalies that occurred during a Weak Nino. Due to the data only going back to 1948, all of the years are not depicted, but this will give you a good idea. 

    As you can see, a weak Nino is what we'd like to see come Dec-Feb. If the current one stays too strong, it could severely limit our cold this winter based on past analogs. keep in mind, Larry's study is based on temperatures, not precipitation.  ​ ​Nino and the Pacific Decadal Oscillation (PDO)
    +PDO or Warm State -PDO or Cold State PDO Index (http://www.daculaweather.com/4_pdo_index.php) While it's easy to look at one specific weather pattern, there are many factors that determine how a winter will turn out, with the ENSO state being just one of those. But there are other teleconnections and long term patterns that also have an effect on our winter weather, and they all work in tandem with each other.  Graphs and Charts

    Now we are going to turn our attention to the PDO state or Pacific Decadal Oscillation. First, the definition from the National Center for Environmental Information:

    "The Pacific Decadal Oscillation (PDO) is often described as a long-lived El Niño-like pattern of Pacific climate variability (Zhang et al. 1997). As seen with the better-known El Niño/Southern Oscillation (ENSO), extremes in the PDO pattern are marked by widespread variations in the Pacific Basin and the North American climate. In parallel with the ENSO phenomenon, the extreme phases of the PDO have been classified as being either warm or cool, as defined by ocean temperature anomalies in the northeast and tropical Pacific Ocean. When SSTs are anomalously cool in the interior North Pacific and warm along the Pacific Coast, and when sea level pressures are below average over the North Pacific, the PDO has a positive value. When the climate anomaly patterns are reversed, with warm SST anomalies in the interior and cool SST anomalies along the North American coast, or above average sea level pressures over the North Pacific, the PDO has a negative value (Courtesy of Mantua, 1999). " 

    Here's an analysis of the cold 26 winters by DJF averaged PDO status:+ PDO: 18 of 58 (31%) - PDO: 8 of 57 (14%) Again, much as it was with weak Nino's, many of our coldest winters occurred during a + PDO state, while only 8 out of 57 occurred during a negative PDO state. ​ Nino and the North Atlantic Oscillation (NAO)
    In order for us to get long lasting cold air that stays locked in, we need some blocking. There are several teleconnection patterns that aid in developing this blocking, one of which is the North Atlantic Oscillation or NAO. Graphs and Charts
    Negative NAO (-NAO) Positive NAO (+NAO) Here's the definition of the NAO:
    "The North Atlantic Oscillation (NAO) is a climatic phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high. Through fluctuations in the strength of the Icelandic low and the Azores high, it controls the strength and direction of westerly winds and storm tracks across the North Atlantic. It is part of the Arctic Oscillation, and varies over time with no particular periodicity."
    Strong positive phases of the NAO tend to be associated with above-average temperatures in the eastern United States and across northern Europe and below-average temperatures in Greenland and oftentimes across southern Europe and the Middle East. They are also associated with above-average precipitation over northern Europe and Scandinavia in winter, and below-average precipitation over southern and central Europe. Opposite patterns of temperature and precipitation anomalies are typically observed during strong negative phases of the NAO. For us, negative is what we're looking for in the winter. 

    Let's take a look at the analysis of the cold 26 Dec-Feb winters by averaged NAO status:

    – NAO: 19 of 48 (40%) + NAO: 7 of 67 (10%) Again, a large number of the cold winters had a negative NAO. ​​ Piecing It All Together...
    Now let's take the combination of the ENSO state (in our case, Nino), and factor in the PDO and NAO and let's see what we get. Here's the analysis of the 26 cold winters by a combination of Dec-Feb averaged PDO and NAO status:+ PDO/-NAO: 12 of 25 (46%) - PDO/-NAO: 7 of 23 (30%) (all 7 had (PDO – NAO) > 0) + PDO/+NAO: 6 of 33 (18%) - PDO/+NAO: 1 of 34 (3%) Things start to change a little. Obviously, the combination of +PDO and -NAO are the best combination, and that makes perfect sense. During the positive phase of the PDO, the wintertime Aleutian low is deepened and shifted southward, warm/humid air is advected along the North American west coast and temperatures are higher than usual from the Pacific Northwest to Alaska but below normal in Mexico and the southeastern United States. Add the effects of the blocking provided by the NAO and you lock in the cold air instead of having it rush out to sea.  Now, let's really lay it out.
    Here's "Brother Larry's" analysis of the 26 cold winters by a combination of ENSO state and Dec-Feb averaged PDO and NAO status:

    Strong Nino:+PDO/-NAO: 0 of 6 (0%) -PDO/-NAO: 0 of 1 (0%) +PDO/+NAO: 0 of 7 (0%) -PDO/+NAO: 0 of 1 (0%)
    Moderate Nino:+PDO/-NAO: 1 of 2 (50%) -PDO/-NAO: 0 of 0 (N/A) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 0 of 2 (0%)
    Weak Nino:+PDO/-NAO: 6 of 7 (86%) -PDO/-NAO: 2 of 2 (100%) +PDO/+NAO: 1 of 2 (50%) -PDO/+NAO: 0 of 4 (0%)
    Neutral Positive:+PDO/-NAO: 2 of 4 (50%) -PDO/-NAO: 0 of 3 (0%) +PDO/+NAO: 2 of 10 (20%) -PDO/+NAO: 0 of 5 (0%)
    Neutral Negative:+PDO/-NAO: 1 of 3 (33%) -PDO/-NAO: 2 of 7 (29%) +PDO/+NAO: 2 of 10 (20%) -PDO/+NAO: 0 of 5 (0%)
    Weak Nina:+PDO/-NAO: 2 of 2 (100%) -PDO/-NAO: 3 of 5 (60%) +PDO/+NAO: 1 of 4 (25%) -PDO/+NAO: 0 of 7 (0%)
    Moderate Nina:+PDO/-NAO: 0 of 1 (0%) -PDO/-NAO: 0 of 3 (0%) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 1 of 4 (25%)
    Strong Nina:+PDO/-NAO: 0 of 0 (N/A) -PDO/-NAO: 0 of 2 (0%) +PDO/+NAO: 0 of 0 (N/A) -PDO/+NAO: 0 of 6 (0%) Conclusions...
    Weak Nino’s give the highest percentage chance for cold of any of the ENSO states by far (with weak Nina’s second); however, a combo of -PDO/+NAO seems to make it difficult even for weak Nino’s. A very impressive 13 of 16 (81%) of the aggregate of weak Nino's and weak Nina's with -NAO were cold. Don't ever bet on cold with either a strong Nino or a strong Nina since none of the 23 were cold. +PDO about doubles the percent chance for cold versus a -PDO. A -NAO more than doubles the percentage chance for cold versus a +NAO and a somewhat higher chance than a +PDO gives. So, I give small edge to –NAO over a +PDO regarding cold prospects. Regardless, both are very important. A +PDO/-NAO combo gives close to twice the percentage chance for cold versus the percentage chance for all PDO/NAO combos in the aggregate. A -PDO/-NAO is the next best combo for cold prospects, but mainly if NAO is more negative than PDO. Don't ever bet on cold with a combination of -PDO/+NAO, since only 1 out of 34 were cold. If there is a +PDO, the chances for a –NAO appear to be high for only weak to moderate Nino’s. The chances appear to only be about 50-50 for strong Nino’s. For neutral ENSO, the chances seem to be surprisingly low (partial negative correlation suggested). The best shot at a +PDO/-NAO combo appears to be with a weak to moderate Nino's. On the other hand, only 3 of 34 (9%) Nina’s had a +PDO/-NAO. A pretty high 17 of 34 (50%) Nina’s had a –PDO/+NAO. A +PDO is difficult with a moderate to strong Nina. Only one out of 16 (6%) had one. A –PDO seems rather difficult with a strong Nino, only 2 out of 15 (13%) had one. +PDO and –PDO winters are about evenly split. But +NAO winters have been a bit more common than -NAO in long term: 58% vs. 42%. Winter Precipitation
    Regarding wintry precipitation for Atlanta, when looking at the three standalone super Nino's (1972-1973, 1982 -1983, 1997-1998) as well as the six strong to super strong 2nd year Nino's (1877-1888, 1888-1889, 1896-1887, 1905-1906, 1940-1941, 1987-1988), Atlanta more often than not, had one major winter storm, but not always:1877-1888: 2.5" 1/3/1878 & a non-major freezing rain followed on 1/9/1878 1888-1889: 6" 2/21/1889 1896-1967: 6.2" 12/2/1896 1905-1906: 6.2" for the season including 3.5"+ major 1/26/1906, measurable snow D, J, and F 1940 -1941: only T of snow 1972 -1973: historic ZR 1/7-8/1973, which included 1" mainly ice pellets; (also, historic snow hit central GA in Feb though Atlanta missed that one) 1982 -1983: 10.3" S/IP for season including 7.9" 3/24/1983 (heaviest since 1940) and measurable snow J, F, and M 1987- 1988: 4.2" of mainly IP 1/7/1988 (would have been ~8" if all snow) 1997- 1998: only 0.6" 12/29/1997 View the full article
  22. NorthGeorgiaWX
    Today in Weather History
    for March 8 

    March 8, 1717 
    On Fishers Island in Long Island Sound, 1200 sheep were discovered to have been buried under a snow drift for four weeks. When finally uncovered, one hundred sheep were still alive. (The Weather Channel) 

    March 8, 1909 
    The town of Brinkley AR was struck by a tornado which killed 49 persons and caused 600,000 dollars damage. The tornado, which was two-thirds of a mile in width, destroyed 860 buildings. Entire families were killed as houses were completely swept away by the tornado. Tornadoes killed 64 persons and injured 671 others in Dallas and Monroe counties during the Arkansas tornado outbreak. (David Ludlum) 

    March 8, 1984 
    A freak thunder snowstorm produced high winds, vivid lightning, and up to seven inches of snow in the northern suburbs of Washington D.C. (Sandra and TI Richard Sanders - 1987) 

    March 8, 1987 
    Thirty-two cities in the eastern U.S. reported new record high temperatures for the date, including Madison WI with a reading of 71 degrees. Afternoon highs of 68 degrees at Houghton Lake MI and 72 degrees at Flint MI smashed their previous records for the date by fourteen degrees. (The National Weather Summary) 

    March 8, 1988 
    A cold front brought wintry weather to the north central U.S. Snowfall totals in northwestern Minnesota ranged up to eight inches at Roseau and Hallock. Winds in South Dakota gusted to 61 mph at Brookings. (The National Weather Summary) (Storm Data) 

    March 8, 1989 
    While arctic cold gripped the northeastern U.S., unseasonably warm weather prevailed across the southwestern states. Albany NY reported a record low of 2 degrees below zero. Tucson AZ reported a record high of 90 degrees. (The National Weather Summary) 

    March 8, 1990 
    Late afternoon thunderstorms produced severe weather in east central Iowa and west central Illinois. Thunderstorms spawned a tornado south of Augusta IL which traveled 42 miles to Marbleton. Golf ball size hail was reported at Peoria IL and near Vermont IL. (The National Weather Summary) (Storm Data) 

    March 8, 2004 
    The California coast warms up. San Francisco broke a 112-year record by reaching 82 degrees. Los Angeles soared to 93 degrees. 

    March 8, 2005 
    A line of strong to severe thunderstorms affected the eastern portions of North and South Carolina, with wind damage and a few tornadoes reported. Winds gusted over 70 MPH with some of the stronger storms. 

    March 8, 2008
    Strong winds combined with the snow and cold temperatures to result in unseasonably winter-like conditions for March. Up to 2 inches of snow fell from Floyd County to Union County in extreme north Georgia with the maximum report of 2.5 inches in Fannin County. (NWS Atlanta)

    Data courtesy of WeatherForYou              
    View the full article
     
  23. NorthGeorgiaWX
    Data from the Atlanta NWS office
    First Snow of the Season in Georgia!
    Early on November 1, 2014, northeast Georgia received their first snow of the season! A strong upper level low dove into eastern Georgia and the Carolinas, bringing wrap-around moisture from the low pressure system to parts of Georgia. In addition, the area was in northwest flow with cold air being ushered into the state. This combination of precipitation and freezing temperatures brought the first snow of the season to Georgia. Even though the accumulation was limited to the northeastern part of the state, snow flurries were observed as far south as the northern portion of the Atlanta metro area! Overall snowfall accumulations ranged from 0.5-2 inches.
    This snow event was unusually early for the season. Although snowfall records across northeast Georgia are somewhat limited, based on records that are available, the previous earliest snowfall at Blairsville was November 10 (1968), at Helen it was November 12 (1968) and at Cleveland it was also November 12 (1968). Please note there is the potential for missing data at these sites.
    500mb Pattern on November 1, 2014 5am Temperatures on November 1, 2014  
    Snowfall Map from November 1, 2014
  24. NorthGeorgiaWX
    All data from the Atlanta NWS office
    Heavy Snowfall
    December 8 - 9, 2017
     
    Event Summary Snow Accumulation Map Recorded Snowfall Totals Event Photos   Event Summary A major early-season heavy snowfall affected north Georgia from Friday, December 8th into the morning of Saturday, December 9th. Many locations recorded up to a foot of snowfall, which is exceptionally rare for Georgia, especially in early December! This heavy snowfall also led to numerous power outages. At the height of the storm over 200,000 customers in north Georgia were in the dark. There was a sharp northwest to southeast gradient of accumulating snow through metro Atlanta. Areas southeast of Atlanta did not receive much accumulating snow, while areas north and west of the city received very significant totals.   Snow Accumulation Map:

    Above: The heaviest snow accumulations occurred in a ribbon stretching from Carroll County into the northwestern Atlanta suburbs and into the north Georgia mountains. Up to a foot of snow accumulated in these areas!  
    Satellite Image December 9th:

    Above: A visible satellite image of north Georgia on the afternoon of Saturday, December 9th shows much of the snow that fell on Friday and early Saturday remained on the ground.   Snowfall Reports Table   For snowfall reports from a specific county, click on the county name of interest below. Counties are sorted alphabetically. (*Note that only counties from which reports were received are listed below.*)   Banks Dawson Hall Polk Barrow DeKalb Haralson Towns Bartow Douglas Henry Troup Carroll Fannin Jackson Union Catoosa Fayette Lumpkin Walker Chattooga Floyd Madison Walton Cherokee Forsyth Murray White Clayton Fulton Muscogee Whitfield Cobb Gilmer Paulding   Coweta Gwinnett Pickens   Event Photos
    Over 10" of snow accumulated in the Brookstone Subdivision in Acworth. (courtesy of Chris Dolce)
    Acworth, GA
    About 13" of snow was recorded in Jasper. (courtesy of Dean Davis)
    Jasper, GA 
    Trees drooped and broke under the weight of a foot of heavy, wet snow in Hiram. (courtesy of Brandie Freeman) 
    Hiram, GA
    About 8" of snow fell at this location along the Cobb/Fulton County border in Roswell. (courtesy @d_mez7)
    Roswell, GA
    The Carroll County Courthouse is covered in several inches of snow. (courtesy of Carroll County Gov't)
    Carrollton, GA
    Snow falling in Midtown Atlanta on December 8, 2017. (courtesy of Jeremy Mills)
    Atlanta, GA
    Several inches of snow accumulated along the Atlanta BeltLine in Inman Park. (courtesy of Atlanta BeltLine)
    Atlanta, GA
    This aerial view of a Fayette County neighborhood shows a blanket of snow on the morning of December 9th. (courtesy @supeshooter)
    Fayette County, GA
    The Union County Historical Courthouse on the morning of December 9th.
    Blairsville, GA
    The heavy snow caused extensive damage to power infrastructure. (Courtesy of Cobb EMC)
    Powder Springs, GA
    This aerial view of Georgia Tech and Midtown Atlanta shows the abundant snow cover. (Courtesy of Zonglin Jack Li)
    Atlanta, GA
    Berry College was picturesque in the snow. (Courtesy of Berry College)
    Rome, GA
     

  25. NorthGeorgiaWX

    Finally....

    By NorthGeorgiaWX,


    Car
    The wheels arrived this week... finally. I ordered the wheels on July 1 so it was a long wait but worth it. I took the car down to Gran Turismo East for the installation of all the new pieces (except for the already done engine tune). 
    Renick RP 556 Wheels Gloss Black Front: 19x9.5” with 265/30-ZR19 Michelin Pilot Sport 4S Rear: 19x11” with 305/30-ZR19 Michelin Pilot Sport 4S Renick front and rear adjustable sway bars Eibach Pro springs Track alignment Trifecta Tune Some people like to take their car to the drag strip while others like the twisty turns or maybe even both. I'm a twisty kind of guy. I've autocrossed since 1973 so I've driven a lot of cars and know what feels good and what doesn't, and I know what modifications need to be done to most any car to get the most out of it. Fortunately this car started off with all the right pieces, it just needed a little tweaking. 
    Right now this car feels incredible. The steering is quick and responsive with plenty of feedback. The grip is incredible for a street tire. I'm used to autocrossing on bias ply race slicks that are squishy and flexible and these new tires are nothing like that at all. The tires are more quiet, have a better ride, and have a lot more grip than the OEM Michelin Pilot Super Sport tires that came on the car. I know part of that increase in grip is increased wheel width along with a corresponding increase in tire size, but what I feel is even more. The zero body roll and instant steering response is confidence inspiring. I couldn't be more pleased with how this car handles. In case you didn't know, the car has the magnetic ride shocks, so you're not going to get better than that. The car has three modes, Tour, Sport, and Track, and as you go up in modes the shocks get firmer and more controlled. These shocks sample the road surface 1000 times a second and can react to every imperfection, so I have no need to ever mess with the shocks.
    I got her (yes, this is Grace so be nice) cleaned up and took some pictures. 













     

Various Links

These are links to various pages on my Daculaweather.com site

NWS Links

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