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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Thu Apr 25 2024 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS AND SOUTHERN NEW MEXICO... Elevated to critical conditions have started to develop across southeast New Mexico. Expect these conditions to expand/worsen through the day as mid-level flow strengthens and lee cyclogenesis continues. Expanded the Elevated delineation slightly farther north based on current and expected position of the front and dryline. Otherwise, no changes were necessary. See previous discussion below. ..Bentley.. 04/25/2024 .PREV DISCUSSION... /ISSUED 0114 AM CDT Thu Apr 25 2024/ ...Synopsis... A midlevel trough will track eastward across the Southwest, while an accompanying 60-70-kt midlevel southwesterly jet overspreads southern NM and the southern High Plains. This will promote rapid deepening of a lee cyclone over eastern CO, while a southward-extending dryline sharpens over west TX. This large-scale pattern evolution will yield an expansive area of critical fire-weather conditions across the aforementioned areas, with high-end critical conditions expected over eastern NM. ...Southern New Mexico and the Southern High Plains... Behind the sharpening dryline, strong downslope warming/drying and diurnal heating will contribute to a deep/dry boundary layer, characterized by surface temperatures in the mid/upper 80s and single-digit to lower-teens RH. Here, a tightening surface pressure gradient peripheral to the deepening lee cyclone, and mixing into the strong flow aloft, will support 25-35 mph sustained southwesterly surface winds (with gusts upwards of 45 mph). These conditions will yield an expansive area of high-end critical fire-weather conditions, given modestly receptive fuels. The overlap of strongest winds and lowest relative humidity is expected over eastern NM, where extremely critical meteorological conditions are likely. However, a lack of abundant and very dry fuels over the area precludes such highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0731 AM CDT Thu Apr 25 2024 Valid 251300Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS WESTERN KS AND TONIGHT ACROSS NORTHWEST TX INTO CENTRAL OK... ...SUMMARY... Very large hail up to 3 inches in diameter and a strong tornado or two will be possible this evening across western Kansas. Large hail up to 2.5 inches in diameter, damaging winds to 70 mph and a few tornadoes will be possible tonight from northwest Texas into central Oklahoma. ...Synopsis... A midlevel shortwave trough and associated 70 kt jet will eject northeastward toward western KS by late tonight and Friday morning. An associated lee cyclone is expected to deepen this afternoon across northeast CO, with a sharpening dryline arcing to its south across western KS and the TX/OK Panhandles. Farther east, a warm front will continue to move northward from OK into KS, though northward progress of the front will be slowed by elevated convection (posing an isolated large hail threat) that will reinforce the cool side of the boundary during the day. A somewhat bimodal threat distribution is expected - the warm sector in western KS and a second corridor overnight from northwest TX into OK. ...Western KS this afternoon/evening... An unstable warm sector will be present through this evening, with boundary-layer dewpoints in the 60s beneath steep midlevel lapse rates. The base of the elevated mixed layer will be relatively warm, suggesting the need for surface temperatures into the 80s on the immediate moist side of the dryline. The better potential for storm development this afternoon will be across western KS, where dryline parcel residence times will be longer and in closer proximity to the left-exit region of the approaching mid-upper jet. The initial dryline storms will likely become supercells capable of producing very large hail of 2-3 inches in diameter, and these storms could continue northeastward as elevated supercells atop the warm front. The potential for a strong tornado or two will increase this evening as the storms encounter richer low-level moisture and increasing low-level shear. However, the window of opportunity will not be particularly large given the presence of a rain-reinforced front to the northeast and increasing convective inhibition by late evening. ...Northwest TX into OK overnight... A general consensus of most overnight forecast guidance suggests a southern corridor of greater hail/wind threat starting early tonight just off the Caprock and then spreading northeastward over northwest TX into southwest/central OK early Friday morning. Thunderstorm initiation will become more probable by 03-06z in association with cooling/moistening at the base of the elevated mixed layer, coincident with the beginning of eastward movement of the dryline/Pacific cold front along the trailing influence of the ejecting midlevel trough. Storm mode will likely trend to clusters/line segments while spreading northeastward. Boundary-layer dewpoints approaching the upper 60s beneath steep midlevel lapse rates will contribute to MUCAPE in excess of 2000 J/kg through the overnight hours, which will favor the potential for both large hail (especially with any embedded supercells) and damaging winds of 60-70 mph. A few tornadoes may also occur with embedded circulations as low-level shear increases tonight. ...TX Panhandle/western OK this afternoon/evening... A conditionally favorable environment for supercells with very large hail and tornadoes will exist this afternoon/evening across the eastern TX Panhandle into western OK. The primary uncertainty here will be lingering convective inhibition and substantial uncertainty in storm coverage/location along the dryline. For these reasons, have lowered the overall severe threat, but maintained some conditional significant severe potential. ..Thompson/Kerr.. 04/25/2024
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No Mesoscale Discussions are in effect as of Thu Apr 25 12:01:02 UTC 2024.
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No watches are valid as of Wed Apr 24 03:02:01 UTC 2024.
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WW 132 SEVERE TSTM TX 232045Z - 240300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 132 NWS Storm Prediction Center Norman OK 345 PM CDT Tue Apr 23 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest Texas * Effective this Tuesday afternoon and evening from 345 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Isolated to scattered thunderstorms are forecast to develop this afternoon into the evening. A few of the stronger storms will probably evolve into supercells and pose a risk for large to very large hail and severe gusts. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 95 miles west northwest of Abilene TX to 75 miles east northeast of Abilene TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU2). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 27030. ...SmithRead more -
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0324 PM CDT Tue Apr 23 2024 Valid 251200Z - 011200Z An active fire weather pattern will become situated over the southern High Plains late this week through the weekend. The passage of multiple mid-level troughs will encourage surface cyclone development and the eastward surge of a dryline each day Thursday-Sunday along the southern High Plains. Critically dry and windy conditions will become situated behind the dryline each day, with 70% Critical probabilities maintained where very windy and dry surface conditions will coincide for several hours during the afternoon. Furthermore, locally Extremely Critical surface winds/RH cannot be ruled out over portions of eastern New Mexico into far western Texas for Day 3/Thursday or Day 5/Saturday, when the core mid-level jet stream from both upper-level troughs overspread the region. By early next week, the ejection of these mid-level troughs, in favor of upper ridging, will encourage a more quiescent fire weather pattern over the southern High Plains, though dry surface conditions should persist. ..Squitieri.. 04/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Apr 23 2024 Valid 232000Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTHWEST TEXAS... ...SUMMARY... Isolated severe thunderstorms capable of producing large hail (potentially 2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. ...20Z Update... Overall forecast outlined in the previous discussion (appended below) remains valid. As mentioned in recently issued MCD 506, a supercell or two should develop across a portion of western North Texas through late afternoon, with large hail of 1.5 to 2.5 inches in diameter and localized severe gusts of 60-70 mph possible. An isolated storm or two is also possible farther south in the Texas Trans Pecos vicinity. Marginally severe hail (i.e. around 1" in diameter) and damaging gusts are possible here as well. Farther north, isolated thunderstorms are still anticipated from northern IL into Lower MI ahead of an approaching shortwave trough and associated cold front. A few strong to severe storms are possible with small to marginally severe hail and damaging winds as the primary hazards (as mentioned in recently issued MCD 507). ...Early tomorrow morning from TX Panhandle into north-central/central OK... Elevated thunderstorms may develop from the northeast TX/eastern OK Panhandles into central/north-central OK within the warm-air advection regime along the northeastern edge of the returning low-level moisture. Steep mid-level lapse rates and favorable cloud-bearing layer shear could support an isolated instance or two of hail with initial development. However, severe coverage is currently expected to remain less than 5%, precluding the introduction of any outlook areas. ..Mosier.. 04/23/2024 .PREV DISCUSSION... /ISSUED 1123 AM CDT Tue Apr 23 2024/ ...Northwest TX... Visible satellite imagery and surface analysis this morning indicate the initial stage of moisture return is occurring across the southern Great Plains in the wake of a frontal intrusion into the Gulf a few days ago. A mid-level ridge will increasingly become established across the central/southern Rockies and adjacent High Plains as a Great Lakes disturbance gradually becomes more displaced from the region. An associated cold front will move southward across KS/OK before eventually stalling tonight across southeast OK and northwest TX. Weak lee cyclogenesis will aid in maintaining a southerly low-level fetch across central into west TX as strong heating results in a sharpening dryline by late afternoon. Isolated thunderstorm development will be most probable near the triple point 20-22Z. Steep lapse rates coupled with adequate moisture (1500-2000 J/kg MLCAPE) and veering flow beneath moderate westerlies, will support an initial supercell mode. Isolated very large hail of 2-2.5 inches in diameter will be the main threat, along with a few 55-65 mph gusts. ...Northern IL/southeast WI/Lower MI late this afternoon/evening... Have not changed the existing outlook for this region due primarily to consistency in model data and the forecast conceptual model not deviating. Water-vapor imagery this morning shows a mid-level trough over the Upper Midwest and this will continue southeast into the central Great Lakes by mid evening. An associated surface trough will likewise move southeastward, and this trough will be preceded by a band of rain with minimal buoyancy. Behind the rain band, surface heating with steepening low-level lapse rates and cooling midlevel temperatures will support weak surface-based buoyancy just ahead of a secondary frontal surge. Some low-topped convection will be possible late this afternoon through late evening from northern IL/southeast WI into Lower MI. The stronger storms could yield a localized marginal hail/damaging wind threat.
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... The previous forecast remains unchanged. ..Squitieri.. 04/23/2024 .PREV DISCUSSION... /ISSUED 0129 AM CDT Tue Apr 23 2024/ ...Synopsis... A low-latitude midlevel trough accompanied by strong southwesterly flow aloft will impinge on the Southwest, where dry antecedent conditions will be in place. This will promote a fairly expansive area of dry/breezy conditions across the region; however, fuels are generally not supportive of large-fire spread at this time. Elsewhere, a limited overlap of warm/dry/breezy conditions will temper fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0131 PM CDT Tue Apr 23 2024 Valid 251200Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE EASTERN TX PANHANDLE AND WESTERN OK INTO SOUTHWEST/SOUTH-CENTRAL KS... AMENDED TO UPDATE FORECAST ...SUMMARY... Severe thunderstorms are likely from late Thursday afternoon into Thursday night across parts of the central and southern Great Plains. Very large hail, severe wind gusts, and strong tornadoes will all be possible. Guidance continues to suggest strong buoyancy will be in place ahead of a negatively tilted shortwave trough ejecting across the southern High Plains. General forecast expressed in the previous outlook remains valid, but confidence in an area of greater severe-weather potential has become more apparent with the most recent guidance. Late afternoon development is anticipated across the TX Panhandle, with these storms quickly becoming severe and capable of large to very large hail up to 3" in diameter. Low-level moisture may be later to arrive in west-central/southwest KS, delaying convective initiation to a few hours later than farther south. Large to very large hail is anticipated with initial development across west-central/southwest KS as well. In both of these areas, storms are expected to move east-northeastward off the dryline, encountering strengthening low-level southerly flow and environment that is increasingly favorable for tornadoes. Low-level shear will continue to strengthening into the early evening, and the overall environment supports the potential for strong to intense tornadoes if a discrete mode can be maintained. --- Previous Discussion issued at 0230 AM CDT Tue Apr 23 2024 --- ...Synopsis... A shortwave trough initially over the Southwest is forecast to take on an increasingly negative tilt as it moves eastward towards the central/southern Plains by Thursday night into Friday morning. In response, a surface low will consolidate and deepen across the central High Plains through the day, before moving northeastward toward northwest KS/southwest NE by Friday morning. An initially stationary surface boundary will move northward as a warm front across the central Plains through the day. Along/south of the warm front, relatively rich low-level moisture will stream northward to the east of a dryline that will become established from the eastern TX Panhandle into western KS and eastern CO. ...Southern/central Great Plains... Coverage of the severe-thunderstorm threat remains somewhat uncertain, but a couple intense supercells are possible by Thursday evening near the dryline from western KS into western OK and the TX/OK Panhandles. Another round of overnight convection will potentially bring the severe threat eastward into a larger portion of the central/southern Plains. The warm sector of the deepening cyclone will likely remain capped for much of the day, though elevated convection may persist from parts of central/eastern KS into eastern OK, to the north of the effective warm front. Increasing moisture beneath steep midlevel lapse rates will support MLCAPE in excess of 2000 J/kg along/east of the dryline, as deep-layer shear strengthens across the region through the day. Ascent attendant to the approaching shortwave trough will begin to impinge upon the warm sector by late afternoon, with isolated supercell development possible near the surface low across southwest KS and southward down the dryline into the TX Panhandle. Very large hail (potentially 2-3 inches in diameter) will likely be the primary initial hazard. A notable increase in low-level flow/shear near and after 00Z will also support a tornado threat with any supercells that can persist into the evening across parts of western KS/OK. While any initial dryline storms may weaken by mid/late evening due to increasing MLCINH with eastward extent, renewed storm development is possible overnight along the Pacific cold front from southwest TX into western/central KS/OK as stronger large-scale ascent overspreads the region. Steep midlevel lapse rates, moderate buoyancy, and strong low-level and deep-layer shear will conditionally support a severe threat with overnight convection across the warm sector, though storm mode may become complex and tend toward a linear evolution with time. Severe wind gusts may become an increasing threat with the nocturnal convection, though hail and a couple tornadoes will also be possible if semi-discrete or embedded supercells can be maintained. ...NE/WY border region into northeast CO... Low-level southeasterly flow will support modest moisture return into parts of northeast CO, southeast WY, and western NE, to the north of the deepening cyclone. Thunderstorm development will be possible near and to the cool side of the effective warm front during the afternoon. While deep-layer shear will be weaker compared to areas farther southeast, steep midlevel lapse rates will support an isolated hail threat. A tornado also cannot be ruled out, if surface-based storms can be maintained within this regime. ..Mosier.. 04/23/2024
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM WEST TEXAS INTO MUCH OF OKLAHOMA... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... Upper pattern is expected to feature a shortwave trough from western Quebec through western New York early Wednesday, with another shortwave well off the southern CA Coast. Shortwave ridging is anticipated between these two troughs. This entire trough/ridge/trough pattern is forecast to move eastward during the period, with the eastern shortwave trough moving off the Northeast/New England coast by Wednesday evening, and the western shortwave trough making steady eastward progress, likely extending from southern NV into southwest AZ/far northwest Mexico by early Thursday morning. Shortwave ridging will be maintained between these troughs, ending the period over the Great Plains. At the surface, a cold front associated with the Northeast shortwave will progress quickly eastward, moving off the Northeast coast by the late afternoon and off the Mid-Atlantic coast later during the evening. Farther west, modest lee troughing is anticipated early Wednesday, with a weak surface low likely over the Texas Trans-Pecos. Lee troughing is expected to sharpen throughout the day, with the surface low likely deepening as well. At the same time, persistent low-level theta-e advection across TX will contribute to the sharpening of a stalled frontal boundary from the southeast TX Panhandle across southern OK. By late Wednesday night/early Thursday morning, this front will likely begin pushing northward across the eastern TX Panhandle and OK as a warm front. ...Eastern TX/OK Panhandles into central OK early Wednesday... Elevated thunderstorms may be ongoing early Wednesday morning from the northeast TX/eastern OK Panhandles into central/north-central OK within the warm-air advection regime along the northeastern edge of the returning low-level moisture. Gradually strengthening westerly flow aloft will support enough vertical shear for organized updrafts and the potential for some storms strong enough to produce large hail. Background height rises cast some doubts for overall storm severity, but thunderstorms will likely persist into the afternoon as they move generally southeastward. ...TX Panhandle through Permian Basin Wednesday afternoon... Low-level moisture is forecast to advect northwestward into the southern High Plains throughout the day. As such, low 60s dewpoints are expected from the TX Panhandle southward to the Big Bend by the early afternoon. Even so, mid-level temperatures and associated capping will likely preclude widespread deep convection. Some isolated development does appear probable, particularly where persistent low-level convergence favors multiple attempts at storm development. Given strong buoyancy and deep-layer vertical shear, any convection that is maintained and matures should become supercellular with the potential to produce large to very large hail and strong, damaging downdrafts. ...TX Panhandle into OK Wednesday night into Thursday morning... Another round of elevated convection is possible from the southern TX Panhandle into northwest TX into OK late Wednesday night into Thursday morning, as low to mid-level moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within any more established storms. ...Northern Mid-Atlantic into Southern New England... Shallow convection is anticipated along and in the wake of the cold front forecast to move quickly eastward/southeastward across the region. Shallow nature to the convection should keep lightning isolated, but a few damaging gusts are still possible as downdrafts augment the moderate westerly low-level flow in place. ..Mosier.. 04/23/2024
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1123 AM CDT Tue Apr 23 2024 Valid 231630Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTHWEST TEXAS... ...SUMMARY... Isolated severe thunderstorms capable of producing large hail (potentially 2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. ...Northwest TX... Visible satellite imagery and surface analysis this morning indicate the initial stage of moisture return is occurring across the southern Great Plains in the wake of a frontal intrusion into the Gulf a few days ago. A mid-level ridge will increasingly become established across the central/southern Rockies and adjacent High Plains as a Great Lakes disturbance gradually becomes more displaced from the region. An associated cold front will move southward across KS/OK before eventually stalling tonight across southeast OK and northwest TX. Weak lee cyclogenesis will aid in maintaining a southerly low-level fetch across central into west TX as strong heating results in a sharpening dryline by late afternoon. Isolated thunderstorm development will be most probable near the triple point 20-22Z. Steep lapse rates coupled with adequate moisture (1500-2000 J/kg MLCAPE) and veering flow beneath moderate westerlies, will support an initial supercell mode. Isolated very large hail of 2-2.5 inches in diameter will be the main threat, along with a few 55-65 mph gusts. ...Northern IL/southeast WI/Lower MI late this afternoon/evening... Have not changed the existing outlook for this region due primarily to consistency in model data and the forecast conceptual model not deviating. Water-vapor imagery this morning shows a mid-level trough over the Upper Midwest and this will continue southeast into the central Great Lakes by mid evening. An associated surface trough will likewise move southeastward, and this trough will be preceded by a band of rain with minimal buoyancy. Behind the rain band, surface heating with steepening low-level lapse rates and cooling midlevel temperatures will support weak surface-based buoyancy just ahead of a secondary frontal surge. Some low-topped convection will be possible late this afternoon through late evening from northern IL/southeast WI into Lower MI. The stronger storms could yield a localized marginal hail/damaging wind threat. ..Smith/Moore.. 04/23/2024
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Apr 23 2024 Valid 231700Z - 241200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, with no changes or additions made. ..Squitieri.. 04/23/2024 .PREV DISCUSSION... /ISSUED 0128 AM CDT Tue Apr 23 2024/ ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0726 AM CDT Tue Apr 23 2024 Valid 231300Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON/EVENING ACROSS NORTHWEST TX... ...SUMMARY... Isolated severe thunderstorms capable of producing large hail (2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. Additional strong storms producing hail up to 1 inch diameter and gusts up to 60 mph are possible from southeast Wisconsin and northern Illinois into Lower Michigan. ...Northwest TX area this afternoon/evening... No appreciable changes to the prior outlook. In the wake of a midlevel trough crossing the Great Lakes, a surface cold front will move southward across KS/OK today, eventually stalling by tonight across southeast OK and northwest TX. There will be sufficient cross-Rockies flow aloft for lee cyclogenesis across eastern NM and adjacent west central TX, which will maintain southerly low-level flow and northward advection of a modifying western Gulf air mass into the frontal zone by mid-late afternoon. Strong surface heating along the west edge of the returning moisture will result in a sharpening dryline by late afternoon, with a dryline/front triple point likely just off the Caprock. Isolated thunderstorm development will be most probable near the triple point after 21z, and convection will subsequently move southeastward before weakening by late evening. The storm environment will be characterized by moderate buoyancy (MLCAPE of 1500-2000 J/kg), steep midlevel lapse rates near 9 C/km, and sufficient deep-layer shear for supercells. Isolated very large hail of 2-2.5 inches in diameter will be the main threat, along with a few 55-65 mph outflow gusts. ...Northern IL/southeast WI/Lower MI late this afternoon/evening... Only minor changes to the MRGL risk area in lower MI. A midlevel trough over the upper MS Valley this morning will continue east-southeastward over the Great Lakes by Wednesday morning. An associated surface trough will likewise move southeastward, and this trough will be preceded by a band of rain with minimal buoyancy. Behind the rain band, surface heating with steepening low-level lapse rates and cooling midlevel temperatures will support weak surface-based buoyancy just ahead of a secondary frontal surge. Some low-topped convection will be possible in this zone late this afternoon through late evening from northern IL/southeast WI into lower MI. The storms could pose a marginal hail/wind threat. ..Thompson/Kerr.. 04/23/2024
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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Tue Apr 23 2024 Valid 261200Z - 011200Z ...DISCUSSION... A complex but active pattern is expected from D4/Friday through D6/Sunday, as multiple mid/upper-level shortwave troughs impinge upon a moist and unstable environment extending from the southern/central Great Plains into parts of the Midwest and Mississippi Valley. ...D4/Friday - Central/southern Plains into the mid MS Valley... A negatively tilted shortwave trough is forecast to move northeastward from the Great Plains toward the mid/upper MS Valley on Friday. Most guidance suggests that convection developing late in the D3/Thursday period will be ongoing Friday morning, potentially posing an organized severe threat as it moves eastward. The influence of early convection on warm sector evolution by Friday afternoon/evening remains uncertain, but in general, moderate destabilization will be possible along the Pacific front/dryline in the wake of early convection, with some intensification of early storms also possible farther east. Details regarding storm mode remain uncertain at this forecast range, but in general, severe storms capable of producing large hail, damaging winds, and a few tornadoes will be possible across a broad region from the eastern Great Plains into the mid MS Valley. ...D5/Saturday - Central/southern Plains into the Midwest/mid MS Valley... The negatively tilted shortwave trough and attendant occluding surface cyclone are forecast to gradually weaken as they move across the upper Great Lakes region on Saturday. Depending on timing of the departing cyclone and magnitude of diurnal destabilization, some severe-thunderstorm threat could evolve in advance of this system through the afternoon across parts of WI/IL into MI, but confidence remains too low to include 15% probabilities for this area. Meanwhile, another strong shortwave trough is forecast to eject across parts of the central/southern Plains Saturday afternoon and evening, accompanied by strong surface cyclogenesis across the central High Plains. Moderate to locally strong instability may redevelop along/east of the dryline across central/western KS/OK into north TX, as low-level and deep-layer shear strengthen through the day. The synoptic pattern depicted by much of the extended-range guidance is suggestive of an active severe thunderstorm episode along/ahead of the dryline, though some guidance (notably recent runs of the ECMWF) suggest potential for early development across parts of OK/north TX, which could complicate the scenario by late afternoon/evening. Some severe threat could spread toward parts of the mid MS Valley late in the period. ...D6/Sunday - ArkLaTex into parts of the Midwest... Predictability begins to decrease by late in the weekend, though in general, a mid/upper-level trough and attendant surface low are forecast to move from the central Plains toward the upper Great Lakes region. A corridor of severe thunderstorm potential is forecast to extend south-southwestward from the surface low, as a trailing cold front moves through a moist, unstable, and favorably sheared environment. A 15% area has been added where confidence is currently greatest in severe-thunderstorm potential Sunday afternoon and evening.
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Flood Warning issued April 22 at 9:19PM EDT until April 24 at 10:24AM EDT by NWS Jacksonville FL
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Flood Warning issued April 22 at 9:17PM EDT by NWS Jacksonville FL
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No Mesoscale Discussions are in effect as of Mon Apr 22 18:01:02 UTC 2024.
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Frost Advisory issued April 22 at 2:00PM EDT until April 23 at 9:00AM EDT by NWS Peachtree City GA
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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Sun Apr 21 2024 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential will remain low through tonight. ...Southeast GA/North FL... Severe probabilities have been removed from southeast GA/northern FL with the 01z update. Weakening large-scale ascent, poor low-level convergence, and a cooling/stabilizing boundary layer post-sunset will suppress severe thunderstorm potential the remainder of the evening. However, sufficient elevated instability may support isolated non-severe thunderstorm near the southward sagging surface front for a few more hours. ..Leitman.. 04/22/2024
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No Mesoscale Discussions are in effect as of Sun Apr 21 21:46:01 UTC 2024.
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0414 PM CDT Sun Apr 21 2024 Valid 231200Z - 291200Z Upper-level ridging over the Plains will promote relatively quiescent fire weather conditions during the middle of the week. By Thursday into the weekend though, a series of mid-level troughs will eject into the southern Plains, supporting the development of multiple surface cyclones and accompanying eastward surges of a dryline over the southern High Plains each day. In the post-dryline environment, Critical overlapping surface westerly winds and RH are expected, with guidance consensus showing the best chance at such conditions occurring along the CO/KS/TX/NM border areas by Thursday-Saturday afternoon peak heating. Here, 70 percent critical probabilities have been introduced for Days 5-7 (Thursday-Saturday), though Critical fire weather concerns may persist into early next week. Higher Critical probabilities may be needed for Sunday and perhaps beyond over the southern High Plains if guidance consensus shows the continued critically dry and windy conditions with any consistency. ..Squitieri.. 04/21/2024 ...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Sun Apr 21 2024 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Guidance consensus continues to show solidly Elevated equivalent winds and RH to overspread portions of the northern High Plains tomorrow afternoon. Still, fuels appear too poorly receptive to support significant wildfire spread, with fire weather highlights withheld this outlook. A dry thunderstorm or two may also occur along portions of the central High Plains tomorrow afternoon, where fuels are at least modestly receptive to wildfire spread. However, confidence in storm coverage to prompt more than a localized wildfire-spread threat via lightning-induced ignitions is too low to introduce isolated dry thunderstorm highlights at this time. ..Squitieri.. 04/21/2024 .PREV DISCUSSION... /ISSUED 0154 AM CDT Sun Apr 21 2024/ ...Synopsis... Along the southern periphery of a midlevel low tracking eastward across southern Canada, a swath of strong deep-layer westerly flow will overspread the northern/central Plains into the Upper MS Valley. At the same time, a cold front will move eastward across the region. Behind the front, 20-30 mph sustained west-northwesterly surface winds (with higher gusts) will overlap the northern edge of low boundary-layer RH across eastern MT into the Dakotas. While this may lead to localized fire-weather concerns, preceding rainfall atop already marginal fuels for some areas, and uncertainty regarding RH reductions, limit confidence in the fire-weather threat -- precluding Elevated highlights at this time. Ahead of the front from the southern Plains into the Midwest, a tight pressure gradient beneath a strong low-level jet will yield 20-25 mph sustained southwesterly surface winds (with gusts upwards of 35 mph). However, RH reductions generally appear marginal across this corridor. Nevertheless, the strong/gusty winds may still promote locally elevated fire-weather conditions where fuels are receptive to fire spread. ...Please see www.spc.noaa.gov/fire for graphic product...
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Frost Advisory issued April 21 at 2:34PM EDT until April 22 at 9:00AM EDT by NWS Peachtree City GA
SPC Apr 25, 2024 1630 UTC Day 1 Convective Outlook
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