WW 660 SEVERE TSTM IN MI LM 280015Z - 280600Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 660 NWS Storm Prediction Center Norman OK 815 PM EDT Tue Aug 27 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Indiana Far Southwest Lower Michigan Lake Michigan * Effective this Tuesday night and Wednesday morning from 815 PM until 200 AM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms will spread southeastward across far southwest Lower Michigan and northern Indiana this evening while posing a threat for mainly severe/damaging winds up to 60-70 mph. Isolated large hail may also occur. The severe thunderstorm watch area is approximately along and 45 statute miles north and south of a line from 55 miles east southeast of South Bend IN to 40 miles southwest of South Bend IN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 658...WW 659... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30035. ...Gleason Read more

WW 0658 Status Updates
STATUS REPORT ON WW 658 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 WNW MMO TO 15 W BEH. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2023 ..DEAN..08/28/24 ATTN...WFO...LOT...MKX... STATUS REPORT FOR WS 658 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC053-063-075-091-093-099-105-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE FORD GRUNDY IROQUOIS KANKAKEE KENDALL LA SALLE LIVINGSTON WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 658 SEVERE TSTM IL IN WI LM 272210Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 658 NWS Storm Prediction Center Norman OK 510 PM CDT Tue Aug 27 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Illinois Northwest Indiana Far Southeast Wisconsin Lake Michigan * Effective this Tuesday afternoon and evening from 510 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Thunderstorms should continue to grow in coverage and intensity this afternoon and evening as they move east-southeastward. Large hail around 1-2 inches in diameter will be a threat with any supercells, but severe/damaging winds generally around 60-70 mph may also occur if thunderstorms can grow into a small cluster. The severe thunderstorm watch area is approximately along and 45 statute miles east and west of a line from 15 miles west of Racine WI to 55 miles southeast of Marseilles IL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 656...WW 657... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30025. ...Gleason Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Tue Aug 27 2024 Valid 280100Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN GREAT LAKES AND PORTIONS OF THE MIDWEST... ...SUMMARY... Severe thunderstorms capable of damaging thunderstorm winds and isolated large hail remain possible across the southern Great Lakes region and portions of the Midwest tonight. ...01z Update... Upper ridge is flattening across the Great Lakes this evening in response to a progressive short-wave trough advancing east across the upper MS Valley. This feature will deamplify as it shifts into the central Great Lakes by 28/12z. Westerly flow is gradually deepening across this region and low-level convergence is not particularly focused, though a synoptic front does currently extend from northern Lower MI/south-central WI arcing into southern NE. Multiple thunderstorm complexes have spread across WI/MI with the leading edge of one MCS now advancing southeast of Lake Erie. This activity should struggle as it propagates into eastern OH/western PA as buoyancy is not particularly strong across this portion of the OH Valley. Upstream along the trailing synoptic front, a reservoir of extreme instability has yet to be overturned from northern IL into northern MO. Robust convection is tracking southeast along a lake breeze near the Chicago metro. These storms will propagate into northern IN over the next several hours with an attendant risk for hail/wind. Farther southwest, weaker steering currents are contributing to slow-moving clusters along the front across northern MO into northeast KS. This activity will be more deviant in storm motion due to weak flow, driven largely by convective outflow and the presence of extreme instability. Hail/wind remain possible with these storms. ..Darrow.. 08/28/2024 Read more

WW 0659 Status Updates
STATUS REPORT ON WW 659 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SW CLE TO 35 N YNG TO 30 NW ERI. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2021 ..SQUITIERI..08/28/24 ATTN...WFO...CLE... STATUS REPORT FOR WS 659 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OHC007-055-280140- OH . OHIO COUNTIES INCLUDED ARE ASHTABULA GEAUGA PAC039-049-280140- PA . PENNSYLVANIA COUNTIES INCLUDED ARE CRAWFORD ERIE LEZ149-169-280140- CW . ADJACENT COASTAL WATERS INCLUDED ARE CONNEAUT OH TO RIPLEY NY Read more

WW 0656 Status Updates
STATUS REPORT ON WW 656 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 ESE AZO TO 25 WNW JXN TO 20 WNW OSC. ..LYONS..08/27/24 ATTN...WFO...GRR...APX... STATUS REPORT FOR WS 656 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC069-075-272240- MI . MICHIGAN COUNTIES INCLUDED ARE IOSCO JACKSON LHZ363-272240- CW . ADJACENT COASTAL WATERS INCLUDED ARE LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO US/CANADIAN BORDER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0657 Status Updates
STATUS REPORT ON WW 657 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 S AZO TO 25 SSW FNT TO 30 S BAX TO 10 ESE BAX TO 15 NNE BAX TO 25 SE APN. ..LYONS..08/27/24 ATTN...WFO...DTX... STATUS REPORT FOR WS 657 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC063-087-091-093-099-115-125-147-151-161-163-272240- MI . MICHIGAN COUNTIES INCLUDED ARE HURON LAPEER LENAWEE LIVINGSTON MACOMB MONROE OAKLAND ST. CLAIR SANILAC WASHTENAW WAYNE LCZ422-423-460-LEZ444-LHZ441-442-443-462-463-464-272240- CW . ADJACENT COASTAL WATERS INCLUDED ARE ST. CLAIR RIVER DETROIT RIVER LAKE ST. CLAIR OPEN LAKE (U.S. PORTION) MICHIGAN WATERS OF LAKE ERIE FROM DETROIT RIVER TO NORTH CAPE MI Read more

MD 2019 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EXTREME NORTHEAST KS INTO CENTRAL/NORTHERN MO AND WESTERN IL
Mesoscale Discussion 2019 NWS Storm Prediction Center Norman OK 0516 PM CDT Tue Aug 27 2024 Areas affected...Extreme northeast KS into central/northern MO and western IL Concerning...Severe potential...Watch unlikely Valid 272216Z - 280015Z Probability of Watch Issuance...20 percent SUMMARY...Isolated damaging gusts and hail are possible into early evening. DISCUSSION...Isolated thunderstorms have developed from south/southeast of Kansas City into northern MO. The environment across this region is quite warm, moist, and unstable, with MLCAPE of 2500-4000 J/kg in place. However, deep-layer flow and vertical shear are generally weak, which should tend to limit storm organization. Given the favorable instability and rather steep low/midlevel lapse rates, the strongest updrafts could briefly pose some hail threat, though localized downbursts may become the most prominent hazard with time. This isolated severe threat may persist into early evening. ..Dean/Gleason.. 08/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX...DVN...SGF...DMX...EAX...TOP... LAT...LON 39479490 40309368 40729288 40199108 40189091 39589006 39008998 38459021 38219179 38239303 38269453 38969515 39479490 Read more

WW 0658 Status Updates
STATUS REPORT ON WW 658 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..08/27/24 ATTN...WFO...LOT...MKX... STATUS REPORT FOR WS 658 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-031-037-043-053-063-075-089-091-093-097-099-103-105-111- 141-197-201-272340- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE COOK DE KALB DUPAGE FORD GRUNDY IROQUOIS KANE KANKAKEE KENDALL LAKE LA SALLE LEE LIVINGSTON MCHENRY OGLE WILL WINNEBAGO INC007-073-089-111-127-272340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-272340- WI Read more

WW 658 SEVERE TSTM IL IN WI LM 272210Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 658 NWS Storm Prediction Center Norman OK 510 PM CDT Tue Aug 27 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Illinois Northwest Indiana Far Southeast Wisconsin Lake Michigan * Effective this Tuesday afternoon and evening from 510 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2 inches in diameter possible SUMMARY...Thunderstorms should continue to grow in coverage and intensity this afternoon and evening as they move east-southeastward. Large hail around 1-2 inches in diameter will be a threat with any supercells, but severe/damaging winds generally around 60-70 mph may also occur if thunderstorms can grow into a small cluster. The severe thunderstorm watch area is approximately along and 45 statute miles east and west of a line from 15 miles west of Racine WI to 55 miles southeast of Marseilles IL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 656...WW 657... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30025. ...Gleason Read more

WW 0659 Status Updates
STATUS FOR WATCH 0659 HAS NOT BEEN ISSUED YET Read more

WW 659 SEVERE TSTM OH PA LE 272235Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 659 NWS Storm Prediction Center Norman OK 635 PM EDT Tue Aug 27 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northern Ohio Far Northwest Pennsylvania Lake Erie * Effective this Tuesday night from 635 PM until Midnight EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...A line of thunderstorms should continue to pose some threat for severe/damaging winds up to 60-70 mph as it moves east-southeastward this evening across parts of northern Ohio and eventually far northwest Pennsylvania. The severe thunderstorm watch area is approximately along and 25 statute miles north and south of a line from 15 miles south of Toledo OH to 20 miles east southeast of Erie PA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 656...WW 657...WW 658... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 30035. ...Gleason Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0447 PM CDT Tue Aug 27 2024 Valid 291200Z - 041200Z In the wake of a midlevel low advancing eastward across the northern Plains, an expansive mid/upper-level ridge will temporarily build over the West through around Day 5/Saturday. While weak surface winds should generally mitigate fire-weather concerns during that time, boundary-layer warming and some drying of fuels is expected, most notably across the Northwest. Thereafter, a midlevel trough/low will approach the Pacific Northwest, with weak midlevel height falls beginning to impinge on coastal OR/WA as early as Day 5/Saturday. Forcing for ascent will not be particularly strong at that time, though gradually increasing midlevel moisture/instability may support an isolated thunderstorm risk along/west of the Cascades (though confidence in this scenario is low). On Days 6-7/Sunday-Monday, the midlevel trough/low will continue east-northeastward across the Northwest, with more substantial midlevel height falls overspreading the region. Increasing midlevel moisture atop a relatively warm/dry boundary layer will support mixed wet/dry thunderstorms, given the ample large-scale ascent. Confidence in thunderstorm development is currently highest across portions of OR on Day 7/Monday -- when the strongest ascent should phase with favorable PW/instability. Dry Thunderstorm probabilities have been withheld owing to uncertainties regarding fuel receptiveness and overall timing of thunderstorm development, though probabilities may eventually be needed as those details become more clear. ..Weinman.. 08/27/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0656 Status Updates
STATUS REPORT ON WW 656 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 ESE AZO TO 25 WNW JXN TO 20 WNW OSC. ..LYONS..08/27/24 ATTN...WFO...GRR...APX... STATUS REPORT FOR WS 656 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC069-075-272240- MI . MICHIGAN COUNTIES INCLUDED ARE IOSCO JACKSON LHZ363-272240- CW . ADJACENT COASTAL WATERS INCLUDED ARE LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO US/CANADIAN BORDER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0657 Status Updates
STATUS REPORT ON WW 657 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 S AZO TO 25 SSW FNT TO 30 S BAX TO 10 ESE BAX TO 15 NNE BAX TO 25 SE APN. ..LYONS..08/27/24 ATTN...WFO...DTX... STATUS REPORT FOR WS 657 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC063-087-091-093-099-115-125-147-151-161-163-272240- MI . MICHIGAN COUNTIES INCLUDED ARE HURON LAPEER LENAWEE LIVINGSTON MACOMB MONROE OAKLAND ST. CLAIR SANILAC WASHTENAW WAYNE LCZ422-423-460-LEZ444-LHZ441-442-443-462-463-464-272240- CW . ADJACENT COASTAL WATERS INCLUDED ARE ST. CLAIR RIVER DETROIT RIVER LAKE ST. CLAIR OPEN LAKE (U.S. PORTION) MICHIGAN WATERS OF LAKE ERIE FROM DETROIT RIVER TO NORTH CAPE MI Read more

WW 0656 Status Updates
STATUS REPORT ON WW 656 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 W BEH TO 25 NE BEH TO 20 SSW GRR TO 35 NNW LAN TO 35 WSW MBS TO 25 NW MBS TO 20 SE HTL TO 35 NNE HTL. ..JEWELL..08/27/24 ATTN...WFO...GRR...APX... STATUS REPORT FOR WS 656 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MIC005-011-015-025-037-045-051-057-065-067-069-075-077-117-129- 159-272140- MI . MICHIGAN COUNTIES INCLUDED ARE ALLEGAN ARENAC BARRY CALHOUN CLINTON EATON GLADWIN GRATIOT INGHAM IONIA IOSCO JACKSON KALAMAZOO MONTCALM OGEMAW VAN BUREN LHZ363-272140- CW . ADJACENT COASTAL WATERS INCLUDED ARE LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO US/CANADIAN BORDER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE Read more

WW 656 SEVERE TSTM MI LM 271745Z - 280000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 656 NWS Storm Prediction Center Norman OK 145 PM EDT Tue Aug 27 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Lower Michigan Lake Michigan * Effective this Tuesday afternoon and evening from 145 PM until 800 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Multiple of storms are expected to spread east-southeastward this afternoon through early evening across western/interior Lower Michigan, with damaging winds and some hail possible. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 35 miles east northeast of Manistee MI to 30 miles west of Kalamazoo MI. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 655... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 28025. ...Guyer Read more

MD 2014 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF CENTRAL/EASTERN KANSAS
Mesoscale Discussion 2014 NWS Storm Prediction Center Norman OK 0202 PM CDT Tue Aug 27 2024 Areas affected...Portions of central/eastern Kansas Concerning...Severe potential...Watch unlikely Valid 271902Z - 272030Z Probability of Watch Issuance...5 percent SUMMARY...Isolated strong/marginally severe winds and small hail are possible this afternoon in central/eastern Kansas. A watch is not likely. DISCUSSION...A few thunderstorms have initiated along an outflow boundary in central Kansas. Additional storms are possible farther east as heating continues this afternoon. Though deep-layer shear is weak, 1500-2000 J/kg MLCAPE will support isolated strong/marginally severe downburst winds as storms collapse. Small hail could occur as well, but warm temperatures in the profile and the mentioned weak shear should limit potential for marginally severe hail. Storms should have a tendency to move northward given the location of the upper-level ridge where continuing modification of the outflow should eventually support strong wind gusts. ..Wendt/Guyer.. 08/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX...TOP...ICT...GID...DDC... LAT...LON 37939636 38149732 38239796 38089859 38099937 38299956 39029929 39149917 39369903 39539704 39099527 38469462 37819478 37939636 Read more

MD 2015 CONCERNING SEVERE THUNDERSTORM WATCH 656... FOR CENTRAL INTO EASTERN LOWER MICHIGAN
Mesoscale Discussion 2015 NWS Storm Prediction Center Norman OK 0246 PM CDT Tue Aug 27 2024 Areas affected...central into eastern Lower Michigan Concerning...Severe Thunderstorm Watch 656... Valid 271946Z - 272145Z The severe weather threat for Severe Thunderstorm Watch 656 continues. SUMMARY...Storms over central Lower Michigan continue to pose a strong to severe wind threat, with gusty wind potential spreading east over the next several hours. DISCUSSION...Storms with extensive outflow have pushed across Lake MI and into western MI, producing locally severe gusts. Although current radar presentation shows rather broken cell structures, fast-moving outflow continues to push east. Given the strongly unstable air mass developing ahead of the outflow, some severe potential will likely spread eastward through the afternoon, with strong to locally severe gusts. Shear remains weak but new development is possible along the outflow with some degree of forward propagation expected. Also aided downdraft potential are precipitable water values in excess of 1.75" and steepening low-level lapse rates into the peak heating hours. ..Jewell/Guyer.. 08/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...APX...IWX...GRR... LAT...LON 42038330 41878468 41918505 42358551 42778555 43158535 43688502 44058476 44198454 44228323 44108293 43508237 42768252 42288291 42038330 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Aug 27 2024 Valid 272000Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE GREAT LAKES AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms capable of damaging thunderstorm winds and occasional large hail and a tornado or two are possible across the Great Lakes region and portions of the Midwest through tonight. ...20z Update... The prior forecast remains largely on track with minor changes. The Slight and Marginal risk area over parts of WI was trimmed behind extensive convection ongoing over the Lake and northern MI. Ongoing severe storms over parts of the Great Lakes are expected to gradually expand in coverage and intensity over southern lower MI, northern IL and IN through the remainder of the afternoon and into the evening/overnight. The primary risk remains damaging winds associated with organized clusters or bowing segments, but hail and a tornado or two will also remain possible. Farther south into parts of the Mississippi Valley and eastern Plains, additional storm development/intensification is probable this afternoon within a warm and unstable air mass ahead of a weak cold front. Vertical shear is somewhat weaker displaced south of the main shortwave trough, but robust boundary-layer heating should suffice for periodic intensification of multicell storms. At least some damaging wind or hail risk may develop with clusters of strong to severe storms across eastern KS and south-central IA from this afternoon through the evening. ..Lyons.. 08/27/2024 .PREV DISCUSSION... /ISSUED 1142 AM CDT Tue Aug 27 2024/ ...Great Lakes/Midwest/Central Plains... A rather complex mesoscale scenario exists particularly across the Great Lakes region, influenced by multiple MCSs/outflows since last evening. Multiple MCVs are apparent across the region including western Upper Michigan, potentially including an MCV with evolving asymmetric quasi-linear convection across east-central Wisconsin late this morning. Within a zone of pre-frontal confluence/augmented outflow, MCS persistence and further upscale/southward peripheral growth is possible into Lower Michigan/northern Illinois into a very unstable air mass, but this is far from certain. For additional short-term information, see Mesoscale Discussion 2013. Where storm clusters do develop and intensify regionally, ample buoyancy, particularly south of the aforementioned late-morning MCS, and sufficient deep-layer shear will support damaging wind and isolated large hail potential. The severe threat could reach as far as the Lake Ontario vicinity late tonight/early Wednesday. Farther southwest, nearer to the cold front and potentially augmented by residual outflow, CAPE and especially vertical shear will be weaker from southeast Iowa/western Illinois into northern Missouri and eastern Kansas/southeast Nebraska. A few organized multicells are possible atop a strongly heated boundary layer, with strong wind gusts and severe hail possible. Read more