Severe Storms

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Tue Feb 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN TENNESSEE AND KENTUCKY INTO UPSTATE NEW YORK... ...SUMMARY... Isolated strong to severe gusts will be possible today from eastern Tennessee and Kentucky into the Northeast. ...Synopsis... A deep upper trough will move rapidly from the upper MS Valley across the Great Lakes through 00Z, and into New England by Thursday morning. An intense 500 mb jet of 120 kt will exist along the east side of the trough, with meridional orientation. At the surface, low pressure will continue to deepen as it moves from Lake Huron early this morning into northern Quebec by 00Z. A fast-moving cold front will extend south from the low, moving from KY and TN across the Appalachians by late afternoon. Ahead of the cold front, a narrow plume of 50s F dewpoints will extend as far north as southwest PA, with 60+ F values from TN/MS southward. Aiding moisture advection early will be 50-60 kt southwesterly 850 mb flow, but winds will quickly veer with frontal passage and drying. ...Parts of eastern TN/KY across the Appalachians into NY/southwest New England... Rain and storms are likely to be ongoing along much of the cold front early this morning, from OH into northern MS. This activity is expected to be rather disorganized, as the front encounters a somewhat moist and weakly unstable air mass. Forecast soundings ahead of the front during the day depict low-topped convective potential, perhaps with little if any lightning. However, given the strong linear forcing along the front and potential for mixing down of the stronger winds just off the surface, will maintain low probabilities for locally strong to severe gusts. ..Jewell/Lyons.. 02/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Tue Feb 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN TENNESSEE AND KENTUCKY INTO UPSTATE NEW YORK... ...SUMMARY... Isolated strong to severe gusts will be possible today from eastern Tennessee and Kentucky into the Northeast. ...Synopsis... A deep upper trough will move rapidly from the upper MS Valley across the Great Lakes through 00Z, and into New England by Thursday morning. An intense 500 mb jet of 120 kt will exist along the east side of the trough, with meridional orientation. At the surface, low pressure will continue to deepen as it moves from Lake Huron early this morning into northern Quebec by 00Z. A fast-moving cold front will extend south from the low, moving from KY and TN across the Appalachians by late afternoon. Ahead of the cold front, a narrow plume of 50s F dewpoints will extend as far north as southwest PA, with 60+ F values from TN/MS southward. Aiding moisture advection early will be 50-60 kt southwesterly 850 mb flow, but winds will quickly veer with frontal passage and drying. ...Parts of eastern TN/KY across the Appalachians into NY/southwest New England... Rain and storms are likely to be ongoing along much of the cold front early this morning, from OH into northern MS. This activity is expected to be rather disorganized, as the front encounters a somewhat moist and weakly unstable air mass. Forecast soundings ahead of the front during the day depict low-topped convective potential, perhaps with little if any lightning. However, given the strong linear forcing along the front and potential for mixing down of the stronger winds just off the surface, will maintain low probabilities for locally strong to severe gusts. ..Jewell/Lyons.. 02/28/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 PM CST Tue Feb 27 2024 Valid 281200Z - 291200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF EASTERN TENNESSEE AND KENTUCKY INTO UPSTATE NEW YORK... ...SUMMARY... Isolated strong to severe gusts will be possible today from eastern Tennessee and Kentucky into the Northeast. ...Synopsis... A deep upper trough will move rapidly from the upper MS Valley across the Great Lakes through 00Z, and into New England by Thursday morning. An intense 500 mb jet of 120 kt will exist along the east side of the trough, with meridional orientation. At the surface, low pressure will continue to deepen as it moves from Lake Huron early this morning into northern Quebec by 00Z. A fast-moving cold front will extend south from the low, moving from KY and TN across the Appalachians by late afternoon. Ahead of the cold front, a narrow plume of 50s F dewpoints will extend as far north as southwest PA, with 60+ F values from TN/MS southward. Aiding moisture advection early will be 50-60 kt southwesterly 850 mb flow, but winds will quickly veer with frontal passage and drying. ...Parts of eastern TN/KY across the Appalachians into NY/southwest New England... Rain and storms are likely to be ongoing along much of the cold front early this morning, from OH into northern MS. This activity is expected to be rather disorganized, as the front encounters a somewhat moist and weakly unstable air mass. Forecast soundings ahead of the front during the day depict low-topped convective potential, perhaps with little if any lightning. However, given the strong linear forcing along the front and potential for mixing down of the stronger winds just off the surface, will maintain low probabilities for locally strong to severe gusts. ..Jewell/Lyons.. 02/28/2024 Read more

WW 0026 Status Updates
STATUS REPORT ON WW 26 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 WNW SBN TO 10 ENE BEH TO 30 SW GRR TO 10 E MKG. ..SPC..02/28/24 ATTN...WFO...IWX...GRR...DTX... STATUS REPORT FOR WS 26 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS INC003-033-039-085-087-091-099-113-141-149-151-183-280640- IN . INDIANA COUNTIES INCLUDED ARE ALLEN DE KALB ELKHART KOSCIUSKO LAGRANGE LA PORTE MARSHALL NOBLE ST. JOSEPH STARKE STEUBEN WHITLEY MIC005-015-021-023-025-027-037-045-057-059-065-067-075-077-081- 091-093-117-139-145-149-155-159-161-280640- MI . MICHIGAN COUNTIES INCLUDED ARE ALLEGAN BARRY BERRIEN BRANCH CALHOUN CASS CLINTON EATON GRATIOT HILLSDALE INGHAM IONIA JACKSON KALAMAZOO KENT LENAWEE LIVINGSTON MONTCALM OTTAWA SAGINAW ST. JOSEPH SHIAWASSEE VAN BUREN WASHTENAW Read more

WW 0027 Status Updates
STATUS REPORT ON WW 27 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..02/28/24 ATTN...WFO...PAH...LSX...ILX...IND...LMK...ILN... STATUS REPORT FOR WT 27 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-023-025-027-033-035-047-049-051-055-059-065-069-077- 079-081-087-101-119-121-127-133-145-151-153-157-159-163-165-181- 185-189-191-193-199-280540- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND CLARK CLAY CLINTON CRAWFORD CUMBERLAND EDWARDS EFFINGHAM FAYETTE FRANKLIN GALLATIN HAMILTON HARDIN JACKSON JASPER JEFFERSON JOHNSON LAWRENCE MADISON MARION MASSAC MONROE PERRY POPE PULASKI RANDOLPH RICHLAND ST. CLAIR SALINE UNION WABASH WASHINGTON WAYNE WHITE WILLIAMSON INC005-013-019-021-025-027-029-031-037-041-043-047-051-055-059- 061-063-065-071-077-079-081-083-093-097-101-105-109-115-117-119- 123-125-129-133-135-137-139-143-145-147-153-155-161-163-167-173- 175-177-280540- Read more

MD 0167 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR SOUTHERN ILLINOIS AND INDIANA INTO PORTIONS OF NORTHERN KENTUCKY AND SOUTHWEST OHIO
Mesoscale Discussion 0167 NWS Storm Prediction Center Norman OK 0746 PM CST Tue Feb 27 2024 Areas affected...southern Illinois and Indiana into portions of northern Kentucky and southwest Ohio Concerning...Severe potential...Watch likely Valid 280146Z - 280345Z Probability of Watch Issuance...95 percent SUMMARY...The severe risk is expected to increase this evening and overnight upper-level ascent and a fast-moving cold front intersect with the retreating dryline. Bowing segments and supercells will be capable of all severe hazards as they spread east along the OH Valley. A new Tornado Watch will likely be needed in the next 1-2 hours. DISCUSSION...Over the last hour, surface obs near STL showed the dryline retreating westward with a surge in dewpoints to the low 60s F. Evening water-vapor and IR imagery showed large-scale ascent beginning to impinge on the warm sector across portions of the mid MS and lower OH Valleys. Weak convection in the well-mixed warm sector to the west has steadily deepened, and should move into more robust surface moisture this evening. Additional convection also appears likely to develop along the cold front surging southeastward across eastern MO later tonight. Low 60s F surface dewpoints and ~1000 J/kg of MLCAPE will support strong updrafts within the warm sector. Very favorable deep-layer shear (50-60 kt) will support a mix of supercells and short bowing segments. Damaging gusts and hail appear likely, given the strong vertical shear and favorable buoyancy. Rapidly increasing low-level shear (evident on area VADs) may support a risk for tornadoes, especially with more sustained supercells. A significant tornado also cannot be ruled out, given very large effective helicity of 400-600 m2/s2 and a 50-60 kt 850 mb jet. Confidence remains low on the exact timing of convective initiation, given that some convective inhibition remains. As ascent begins to deepen, most hi-res guidance, and extrapolation of weaker convection farther west, suggests new storms should develop in the next 1-2 hours and quickly become severe. With all severe hazards possible, a new Tornado Watch is likely needed in the next couple of hours for parts of southern IL/ IN into northern KY and southwestern OH. ..Lyons/Edwards.. 02/28/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...IND...PAH...ILX...LSX... LAT...LON 36848841 36748893 36778938 37198983 37468988 37978985 38718946 39188830 40018593 40278485 40188455 39788434 39268422 38748426 38288439 37958475 37428636 36888832 36848841 Read more

WW 0027 Status Updates
STATUS REPORT ON WW 12 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SE AAF TO 25 WSW TLH TO 25 E DHN. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0095 ..WEINMAN..01/27/24 ATTN...WFO...TAE... STATUS REPORT FOR WT 12 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC039-065-073-129-272240- FL . FLORIDA COUNTIES INCLUDED ARE GADSDEN JEFFERSON LEON WAKULLA GAC007-087-131-201-205-253-275-272240- GA . GEORGIA COUNTIES INCLUDED ARE BAKER DECATUR GRADY MILLER MITCHELL SEMINOLE THOMAS GMZ730-755-272240- CW Read more

MD 0168 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR LOWER MICHIGAN AND NORTHERN INDIANA
Mesoscale Discussion 0168 NWS Storm Prediction Center Norman OK 0828 PM CST Tue Feb 27 2024 Areas affected...Lower Michigan and northern Indiana Concerning...Severe potential...Watch likely Valid 280228Z - 280330Z Probability of Watch Issuance...80 percent SUMMARY...Severe threat will increase across lower Michigan and northern Indiana late this evening. Wind/hail are the primary risks. Severe thunderstorm watch will likely be issued to account for these risks. DISCUSSION...High-level diffluent flow is overspreading the central Great Lakes this evening ahead of progressive MS Valley short-wave trough. Boundary-layer moisture has increased substantially across lower MI where mid 50s surface dew points are currently observed. While surface-based instability is currently capped, sustained ascent/moistening aloft will contribute to substantial, weakly inhibited buoyancy by mid evening. Forecast soundings across this region suggest parcels lifted near 850mb will yield MUCAPE in excess of 1500 J/kg. Convection that developed over northern IL has grown upscale and is now a mature MCS as it spreads across the western portion of southern Lake MI. Additionally, a well-defined MCV has evolved near the lakeshore over eastern Lake County. While it's not entirely clear how this complex of storms will be affected as it spreads east, sustained low-level warm advection and steep lapse rates suggest this activity will likely have longevity as it spreads across lake MI into lower MI. While the ongoing storm mode and forecast soundings suggest hail/wind will be the primary risks, a brief tornado can not be ruled out. ..Darrow/Edwards.. 02/28/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DTX...IWX...GRR... LAT...LON 42808670 43198441 42308381 41818470 41518676 42808670 Read more

WW 0026 Status Updates
STATUS FOR WATCH 0026 HAS NOT BEEN ISSUED YET Read more

WW 0026 Status Updates
STATUS FOR WATCH 0026 HAS NOT BEEN ISSUED YET Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ESE MMO TO 25 SW RAC. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC031-091-097-197-280340- IL . ILLINOIS COUNTIES INCLUDED ARE COOK KANKAKEE LAKE WILL INC007-073-089-111-127-280340- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280340- WI . WISCONSIN COUNTIES INCLUDED ARE KENOSHA RACINE WALWORTH Read more

WW 25 TORNADO IA IL IN WI LM 272155Z - 280400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 25 NWS Storm Prediction Center Norman OK 355 PM CST Tue Feb 27 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southeast Iowa Northern Illinois Northwest Indiana Southeast Wisconsin Lake Michigan * Effective this Tuesday afternoon and evening from 355 PM until 1000 PM CST. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Widespread large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging wind gusts to 70 mph possible SUMMARY...Thunderstorms will intensify across the watch area in the next hour or two, with a few supercells possible. Very large hail and a tornado or two are the main threats through the evening. The tornado watch area is approximately along and 50 statute miles north and south of a line from 80 miles west of Marseilles IL to 35 miles north of Valparaiso IN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and 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. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 400. Mean storm motion vector 27035. ...Hart Read more

WW 0025 Status Updates
STATUS REPORT ON WW 25 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 N BMI TO 45 SW RFD TO 20 W RFD. ..SPC..02/28/24 ATTN...WFO...DVN...LOT...ILX...MKX... STATUS REPORT FOR WT 25 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-031-037-043-053-063-075-089-091-093-097-099-103-105-111- 141-197-201-280240- 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 INC007-073-089-111-127-280240- IN . INDIANA COUNTIES INCLUDED ARE BENTON JASPER LAKE NEWTON PORTER WIC059-101-127-280240- Read more

MD 0166 CONCERNING TORNADO WATCH 25... FOR NORTHERN ILLINOIS
Mesoscale Discussion 0166 NWS Storm Prediction Center Norman OK 0559 PM CST Tue Feb 27 2024 Areas affected...Northern Illinois Concerning...Tornado Watch 25... Valid 272359Z - 280130Z The severe weather threat for Tornado Watch 25 continues. SUMMARY...Severe thunderstorm clusters, including supercells with the possibility for tornadoes, will spread/develop east toward southern Lake MI over the next several hours. DISCUSSION...Secondary surface low appears to be evolving along the front over southeast IA/northwest IL. A multifaceted corridor of low-level convergence arcs east from this feature across northern IL. Over the last few hours significant boundary-layer moistening has advanced as far north as Rockford where surface dew points are now in the lower 50s. Over the next few hours, low-level flow may back slightly downstream, in advance of the low. This should aid convergence along the warm front currently draped from Henry-La Salle-Iroquois County IL. Several maturing thunderstorm clusters are currently located from south of Davenport IA to DeKalb IL. Significant rotation is now observed with several supercells embedded along this corridor. Given the steep lapse rates observed, very large hail can be expected with this activity. Tornado threat is also increasing as environmental parameters become more favorable along the warm front. This activity should spread toward the southern portions of Lake MI, including the metro Chicago area. ..Darrow.. 02/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...MKX...DVN... LAT...LON 42069020 42678699 41248699 40639022 42069020 Read more

MD 0165 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF CENTRAL AND SOUTHERN ILLINOIS INTO WESTERN INDIANA
Mesoscale Discussion 0165 NWS Storm Prediction Center Norman OK 0547 PM CST Tue Feb 27 2024 Areas affected...parts of central and southern Illinois into Western Indiana Concerning...Severe potential...Watch possible Valid 272347Z - 280115Z Probability of Watch Issuance...40 percent SUMMARY...Isolated storm development along the dryline is possible early this evening. Experimental WOFS guidance and environmental analysis suggest conditional severe potential if supercells are able to develop. DISCUSSION...As of 2230 UTC, regional satellite data showed towering altocumulus deepening across parts of central IL. Located along the dryline ahead of a subtle shortwave trough, multiple attempts at CI appear to be underway. The environment downstream of the dryline is conditionally favorable for deep convection, with dewpoints in the upper 50s to low 60s F and steep mid-level lapse rates supporting 1500-2000 J/kg of MLCAPE. Considerable MLCINH (-100 J/kg from mesoanalysis) remains in place, but if deep convection can initiate, 50+ kt of effective shear would favor storm organization with a supercellular mode. Hi-res and experimental forecast guidance has shown isolated storm development early this evening over several prior runs. Should this occur, the environment over eastern IL and western IN is favorable for supercells capable of all severe hazards. ESRH of 300-400 m2/s2, observed from area VWPs, may also support a risk for a strong tornado. While the risk remains very uncertain, given dry air entertainment and the loss of diurnal heating along the dryline, observational trends are being monitored for a possible weather watch. Storm development is much more likely later this evening as the cold front and stronger forcing for ascent approach from the west after 03z. ..Lyons/Edwards.. 02/27/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...IND...PAH...ILX...LSX... LAT...LON 37958969 37818925 38028870 38298808 38718704 39138667 39608666 39778676 39958695 40108734 40118805 40038834 39808890 39598926 39298952 38418970 37958969 Read more