Severe Thunderstorm Warning issued August 31 at 7:54PM EDT until July 31 at 9:00PM EDT by NWS View the full article

Flood Advisory issued August 17 at 9:57AM EDT by NWS View the full article

MD 1767 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL AND NORTHERN ILLINOIS AND WESTERN INDIANA Mesoscale Discussion 1767 NWS Storm Prediction Center Norman OK 0800 AM CDT Sat Aug 17 2019 Areas affected...central and northern Illinois and western Indiana Concerning...Severe potential...Watch unlikely Valid 171300Z - 171500Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorms will continue to move out of Missouri and into central Illinois this morning. Additional thunderstorms will be possible across northern Illinois as well. Hail and gusty winds may be possible with the strongest cores. The area will be monitored for potential watch, but current indications are that the threat should remain sufficiently isolated to not warrant one. DISCUSSION...Long-lived cluster of thunderstorms continues to move east from northern Missouri into central Iowa. Most-unstable CAPE along and ahead of this cluster is around 1000-1500 J/kg; however, deep-layer shear is generally less than 25 knots. Thus, although a severe hail or strong thunderstorm wind gust will be possible with the strongest cores, the threat should remain sufficiently isolated/episodic that a watch is not currently anticipated for this activity. To the north, across northern Illinois, additional thunderstorms may develop within a belt of stronger midlevel flow, likely in response to ageostrophic forcing from the mesoscale convective system to the southwest. The result will be thunderstorms developing in an objectively analyzed environment of most-unstable CAPE around 1000-1500 J/kg and deep-layer shear of 40-50 knots. Although this would normally suggest a threat for organized severe thunderstorms, considerable uncertainty remains regarding convective coverage and longevity. As such, area will continue to be monitored for potential watch, but expectations are that the threat will remain too isolated in nature to warrant watch issuance. ..Marsh/Edwards.. 08/17/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IWX...IND...LOT...ILX...LSX...DVN... LAT...LON 39948994 41609062 42338945 41488669 39198715 38529025 39948994 Read more View the full article

Saturday, August 17 2019 Preference: Blend of the 00Z GFS/ECMWF, and GEFS/ECENS means Confidence: Average The large scale flow across the CONUS will remain broadly cyclonic through the weekend, although gradual height rises are expected by later Sunday and early next week across the central and southern U.S. Shortwaves rotating through the flow will be the primary sensible weather makers, and it is discrepancy among these features that lead to the preferred blend. The most notable differences involve the 00Z NAM which continues to be a relatively strong outlier with several of these vort lobes impacting the Plains/Midwest that are shedding around a complex of upper lows in Canada. In fact, the NAM gradually becomes out of tolerance with the global model consensus across much of central/southern Canada by the end of the period. The 00Z UKMET also is problematic with energy it has lifting up across the upper Midwest through early Sunday as it is sharper and stronger with a surface wave lifting up along a cold front crossing this region. The UKMET also is out of tolerance across Canada versus the model consensus, which is strongly supported at this point by the 00Z GFS and 00Z ECMWF overall. Across the Southeast and Mid-Atlantic coastal plain, a persistent and quasi-stationary frontal zone is expected to be the focus for multiple waves of low pressure. One wave of low pressure will eject northeast off the Mid-Atlantic coast and out to sea on Saturday. Meanwhile, a second wave of low pressure situated already down across northern FL will lift northeast very close to the Southeast and southern-Mid-Atlantic coastline through Sunday before then exiting offshore and out to sea on Monday. The 00Z NAM, 00Z CMC and especially the 00Z UKMET intensify this low center as it lifts northeast up the coast, with the 00Z GFS and 00Z ECMWF showing more modest development. A large number of Canadian ensemble members and a fair number of the GEFS members favor at least a modest low center, with the vast majority of the ECENS members more ill-defined. The 00Z NAM-conest, 00Z ARW/ARW2 solutions show a bit more development comparable to the NAM, but the 00Z NMMB is a weak outlier. There is strong support toward a GFS/ECMWF blend out of the latest GEFS/ECENS means across the CONUS, and thus a blend of all of these will be preferred at this point. However, a slightly stronger version of the GFS/ECMWF solutions is suggested along the Southeast and Mid-Atlantic coasts with the low center lifting northeast across these areas on Sunday.  

MD 1766 CONCERNING SEVERE THUNDERSTORM WATCH 589... FOR EASTERN KANSAS AND MISSOURI Mesoscale Discussion 1766 NWS Storm Prediction Center Norman OK 0440 AM CDT Sat Aug 17 2019 Areas affected...eastern Kansas and Missouri Concerning...Severe Thunderstorm Watch 589... Valid 170940Z - 171145Z The severe weather threat for Severe Thunderstorm Watch 589 continues. SUMMARY...Thunderstorm intensity continues to decrease across most of the area, and this trend should continue. The lone exception is a storm moving southeast toward southwest Missouri. Gusty winds and hail will be the main threat with this storm. A new watch is currently not anticipated. DISCUSSION...Widespread thunderstorm activity and effects from what appears to be a large heat burst across south-central Kansas appear to have stabilized much of the airmass across Kansas. The effect of this is an general decrease of thunderstorm intensity. Farther east, across far eastern Kansas and western Missouri, a more favorable thermodynamic environment for thunderstorms remains in place, where most-unstable CAPE values around 2000 J/kg exist. However, the kinematic environment is more hostile to thunderstorm organization with deep-layer shear generally less than 25 knots. The most intense thunderstorm across the central United States is moving across west-cental Missouri, within the aforementioned environment. Given the current thunderstorm organization and favorable thermodynamic environment ahead of the storm, continued gusty winds and hail will be possible with this storm in the short term. However, with time, thunderstorm organization will lessen and therefore the thunderstorm should weaken. In fact, recent radar imagery suggests this may already be underway with indications of a turn to the east occurring. To the northeast, across northeast Missouri, a couple of thunderstorms have briefly intensified within the last hour. The thermodynamic environment here is weaker than farther southwest, but the deep-layer shear is better. Current suggestion is that although a brief severe hail or wind threat may develop with any sustained/intense updraft, the overall threat should remain limited and a new watch will not be needed. ..Marsh.. 08/17/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...SGF...EAX...OAX...TOP...ICT... LAT...LON 38209787 38949791 38979735 40359734 40359688 40529686 40519644 40279647 40249506 40159506 40139462 40049460 40029422 40129418 40119377 40269374 40239332 40069337 40009228 39259233 38689264 38689307 38519307 38529354 38239352 38199406 38049405 38069593 38199596 38159635 38089637 38119718 38179718 38209787 Read more View the full article