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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1235 AM CDT Fri Apr 18 2025 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN PLAINS TO THE GREAT LAKES... ...SUMMARY... Scattered severe thunderstorms are possible from parts of the southern Plains northeastward toward the upper Great Lakes from late afternoon into early Saturday morning. Large hail and isolated severe gusts will be the main hazards, especially across the southern Plains where storms will be more concentrated. ...Discussion... Strong 500mb speed max is currently digging south across the northern Inter-Mountain Region. This feature will encourage a pronounced upper trough to evolve over the southwestern U.S. by the end of the period. A broad zone of strong mid-level flow will extend across northern Mexico-southern Plains-Great Lakes as height falls gradually spread into this corridor of the CONUS. As this trough deepens into lower latitudes, surface pressures will rise in the lee of the Rockies over the Plains, and a sharp cold font will surge into western IA-southern KS-OK Panhandle by the start of the period. This boundary will likely serve as a focus for robust convection through the period, and it should extend from eastern WI-western MO-northern TX Panhandle by early evening. Latest model guidance does not allow the upper Midwest/Great Lakes region to destabilize appreciably as buoyancy will be somewhat limited across this region. Even so, strong flow/shear warrant some concern for convective organization, and some risk for wind/hail will accompany frontal/pre-frontal storms as the boundary advances east through the period. Of more concern is the air mass across the southern Plains. Strong boundary-layer heating is expected across the High Plains from eastern NM into northwest TX, just south of the front. The northeast extent of this steep low-level lapse rate plume will likely extend into central OK. Latest model guidance suggests strong SBCAPE will evolve east of the dryline, and south of the front. As temperatures warm through the mid 80s convective temperatures will be breached along the dryline, likely by 21z. Forecast soundings support this and supercells are expected. This activity should grow upscale and spread northeast along the frontal zone. A considerably amount of post-frontal elevated convection is ultimately expected, and steep mid-level lapse rates favor hail with the elevated storms. While the frontal zone will prove sharp, with significant undercutting of updrafts, there is some risk for tornadoes prior to this occurring. Latest NAM guidance has 500mb temperature cooling to -15C at FSI by 04z, thus very large hail can be expected with supercells. Cold front will gradually sag southeast during the overnight hours, but an extended convective event is likely from western OK into the Mid-MS Valley due to the evolution of the longer-wave pattern. ..Darrow/Wendt.. 04/18/2025 Read more

WW 0141 Status Updates
STATUS REPORT ON WW 141 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SE SDA TO 45 NE SDA TO 35 W DSM. ..BENTLEY..04/18/25 ATTN...WFO...DMX...OAX...GID... STATUS REPORT FOR WT 141 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC001-003-039-053-117-121-159-173-175-181-185-180440- IA . IOWA COUNTIES INCLUDED ARE ADAIR ADAMS CLARKE DECATUR LUCAS MADISON RINGGOLD TAYLOR UNION WARREN WAYNE 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 0141 Status Updates
STATUS REPORT ON WW 141 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SE SDA TO 45 NE SDA TO 35 W DSM. ..BENTLEY..04/18/25 ATTN...WFO...DMX...OAX...GID... STATUS REPORT FOR WT 141 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC001-003-039-053-117-121-159-173-175-181-185-180440- IA . IOWA COUNTIES INCLUDED ARE ADAIR ADAMS CLARKE DECATUR LUCAS MADISON RINGGOLD TAYLOR UNION WARREN WAYNE 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 141 TORNADO IA NE 172145Z - 180500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 141 NWS Storm Prediction Center Norman OK 445 PM CDT Thu Apr 17 2025 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Western Iowa Eastern Nebraska * Effective this Thursday afternoon from 445 PM until Midnight CDT. * Primary threats include... A couple tornadoes possible Scattered large hail likely with isolated very large hail events to 3 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Severe storms are expected to increase from west to east near a boundary that extends across the region. Large hail will be the most common risk, but damaging winds are also expected, and a risk for tornadoes will increase through early evening. The tornado watch area is approximately along and 60 statute miles north and south of a line from 55 miles southeast of Denison IA to 60 miles southwest of Columbus NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 140... 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 550. Mean storm motion vector 24025. ...Guyer Read more

MD 0464 CONCERNING TORNADO WATCH 141... FOR SOUTHERN IOWA
Mesoscale Discussion 0464 NWS Storm Prediction Center Norman OK 0950 PM CDT Thu Apr 17 2025 Areas affected...southern Iowa Concerning...Tornado Watch 141... Valid 180250Z - 180415Z The severe weather threat for Tornado Watch 141 continues. SUMMARY...The severe threat will continue for another hour or two. DISCUSSION...Two mature supercells continue to move across southern Iowa. These supercells have now transited the best low-level moisture and are moving toward lesser instability. In addition, boundary layer cooling will continue to increase surface based inhibition this evening and into the overnight hours. The increasingly hostile thermodynamic environment should eventually bring an end to the severe weather threat within the next hour or two across southern Iowa. In the meantime, large hail, severe wind gusts, and perhaps a tornado remain possible threats with these supercells as their strong mid-level pressure perturbations permit them to persist despite the aforementioned unfavorable conditions. ..Bentley.. 04/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...OAX... LAT...LON 40769367 40769404 40779474 40859506 41099495 41459454 41509326 40849309 40769367 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

WW 0141 Status Updates
STATUS REPORT ON WW 141 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 WNW FNB TO 25 SSE OMA TO 35 ENE OMA TO 40 WNW DSM. ..BENTLEY..04/18/25 ATTN...WFO...DMX...OAX...GID... STATUS REPORT FOR WT 141 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC001-003-009-029-071-129-137-145-155-159-165-173-175-180340- IA . IOWA COUNTIES INCLUDED ARE ADAIR ADAMS AUDUBON CASS FREMONT MILLS MONTGOMERY PAGE POTTAWATTAMIE RINGGOLD SHELBY TAYLOR UNION 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

MD 0463 CONCERNING SEVERE THUNDERSTORM WATCH 140... FOR NORTHWEST IOWA INTO SOUTH-CENTRAL MINNESOTA
Mesoscale Discussion 0463 NWS Storm Prediction Center Norman OK 0806 PM CDT Thu Apr 17 2025 Areas affected...Northwest Iowa into south-central Minnesota Concerning...Severe Thunderstorm Watch 140... Valid 180106Z - 180230Z The severe weather threat for Severe Thunderstorm Watch 140 continues. SUMMARY...A few stronger elevated storms may produce marginally severe hail. DISCUSSION...On the eastern edge of a plume of steep mid-level lapse rates, convection has formed behind the cold front due to weak warm advection over the boundary. 40-50 kts of effective shear will promote some risk of large hail with these storms. However, limited elevated buoyancy will limit the overall threat. Though parts of north-central Iowa are still ahead of the cold front, surface cooling has already contributed to an increase in MLCIN. The potential for development along/ahead of the front would appear to be low. If storms do develop, a similar hail and isolated wind damage threat would exist prior to the front undercutting convection. ..Wendt.. 04/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...DMX...FSD...OAX... LAT...LON 42269651 42239689 42429702 43609613 44069510 44229467 44249410 44239352 44079339 43379446 42549583 42339629 42269651 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 0462 CONCERNING TORNADO WATCH 141... FOR FAR EASTERN NEBRASKA AND SOUTHWEST IOWA
Mesoscale Discussion 0462 NWS Storm Prediction Center Norman OK 0737 PM CDT Thu Apr 17 2025 Areas affected...far eastern Nebraska and southwest Iowa Concerning...Tornado Watch 141... Valid 180037Z - 180130Z The severe weather threat for Tornado Watch 141 continues. SUMMARY...The tornado threat will be maximized over the next hour across far eastern Nebraska and southwest Iowa DISCUSSION...Two strong, mature supercells with a history of 2 to 2.75 inch hail, wind gusts up to 82 mph and a few tornadoes, continue east this evening. The tornado threat has increased substantially over the past hour as the low-level jet has strengthened from 35 to 45 knots (per TWX VWP). This low-level jet will strengthen further this evening which will lead to continually increasing low-level shear. However, the boundary layer will start to cool rapidly as the sun sets which should eventually limit the tornado threat. Therefore, the combination of sufficient surface based instability and increasing low-level shear should lead to a favorable (~1 hour) window for a continued tornado threat, before the threat transitions to primarily large hail and severe wind gusts later this evening. An additional watch/watch extension may be needed later this evening. ..Bentley/Guyer.. 04/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...OAX... LAT...LON 40819641 41249598 41499575 41609523 41289470 40849481 40679558 40689627 40819641 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN Read more

WW 0141 Status Updates
STATUS REPORT ON WW 141 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SSW BIE TO 10 ESE LNK TO 10 NNE OMA TO 15 SSW DNS TO 10 S SLB. ..BENTLEY..04/18/25 ATTN...WFO...DMX...OAX...GID... STATUS REPORT FOR WT 141 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC003-009-027-029-047-071-129-137-145-155-165-173-180240- IA . IOWA COUNTIES INCLUDED ARE ADAMS AUDUBON CARROLL CASS CRAWFORD FREMONT MILLS MONTGOMERY PAGE POTTAWATTAMIE SHELBY TAYLOR NEC025-055-067-097-109-131-153-180240- NE . NEBRASKA COUNTIES INCLUDED ARE CASS DOUGLAS GAGE JOHNSON LANCASTER OTOE SARPY 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

MD 0461 CONCERNING SEVERE THUNDERSTORM WATCH 140... FOR SOUTHEAST MINNESOTA INTO NORTHWEST IOWA
Mesoscale Discussion 0461 NWS Storm Prediction Center Norman OK 0556 PM CDT Thu Apr 17 2025 Areas affected...Southeast Minnesota into Northwest Iowa Concerning...Severe Thunderstorm Watch 140... Valid 172256Z - 180100Z The severe weather threat for Severe Thunderstorm Watch 140 continues. SUMMARY...Storms in southeast Minnesota will pose a short-term threat for small to marginally severe hail and perhaps isolated wind damage. Additional development, though not certain, is possible in Northwest Iowa. Large hail and damaging winds would be the main threat in that area. DISCUSSION...A line of storms south of the Twin Cities will continue eastward. This line has shown a weakening trend over the last hour as it has encountered cooler/drier air. Isolated wind damage and small to marginally sever hail could occur with this activity, but a continued downward trend in intensity is expected. A small zone of greater surface heating ahead of the cold front is situated in northwest Iowa. As an upstream shortwave perturbation moves towards the area this evening, modestly increasing frontal convergence and mid-level ascent could promote an additional storm or two within this zone. Should storms form here, steep mid-level lapse rates and 40 kts of effective shear will support large hail and damaging wind potential. ..Wendt.. 04/17/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ARX...MPX...DMX...FSD... LAT...LON 42299536 42279594 42319622 42489614 42889588 43759492 44189462 44449410 44539336 44269239 43779237 42819424 42399481 42299536 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

WW 0140 Status Updates
STATUS REPORT ON WW 140 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNW SUX TO 45 WSW SPW TO 20 WNW FRM TO 25 NNE MKT TO 25 NNE EAU AND 20 NNW SUX TO 40 WSW SPW TO 20 WNW FRM TO 10 NW MKT TO 25 NNW LSE. ..WENDT..04/18/25 ATTN...WFO...FSD...DMX...MPX...ARX... STATUS REPORT FOR WS 140 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC021-025-035-041-059-063-081-091-093-109-141-147-151-161-189- 193-195-180140- IA . IOWA COUNTIES INCLUDED ARE BUENA VISTA CALHOUN CHEROKEE CLAY DICKINSON EMMET HANCOCK HUMBOLDT IDA KOSSUTH O'BRIEN PALO ALTO POCAHONTAS SAC WINNEBAGO WOODBURY WORTH MNC013-039-043-047-091-099-109-147-161-180140- MN . MINNESOTA COUNTIES INCLUDED ARE BLUE EARTH DODGE FARIBAULT FREEBORN MARTIN MOWER OLMSTED STEELE WASECA Read more

WW 0140 Status Updates
STATUS REPORT ON WW 140 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNW SUX TO 45 WSW SPW TO 20 WNW FRM TO 25 NNE MKT TO 25 NNE EAU AND 20 NNW SUX TO 40 WSW SPW TO 20 WNW FRM TO 10 NW MKT TO 25 NNW LSE. ..WENDT..04/18/25 ATTN...WFO...FSD...DMX...MPX...ARX... STATUS REPORT FOR WS 140 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC021-025-035-041-059-063-081-091-093-109-141-147-151-161-189- 193-195-180140- IA . IOWA COUNTIES INCLUDED ARE BUENA VISTA CALHOUN CHEROKEE CLAY DICKINSON EMMET HANCOCK HUMBOLDT IDA KOSSUTH O'BRIEN PALO ALTO POCAHONTAS SAC WINNEBAGO WOODBURY WORTH MNC013-039-043-047-091-099-109-147-161-180140- MN . MINNESOTA COUNTIES INCLUDED ARE BLUE EARTH DODGE FARIBAULT FREEBORN MARTIN MOWER OLMSTED STEELE WASECA Read more

WW 0140 Status Updates
STATUS REPORT ON WW 140 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNW SUX TO 45 WSW SPW TO 20 WNW FRM TO 25 NNE MKT TO 25 NNE EAU AND 20 NNW SUX TO 40 WSW SPW TO 20 WNW FRM TO 10 NW MKT TO 25 NNW LSE. ..WENDT..04/18/25 ATTN...WFO...FSD...DMX...MPX...ARX... STATUS REPORT FOR WS 140 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC021-025-035-041-059-063-081-091-093-109-141-147-151-161-189- 193-195-180140- IA . IOWA COUNTIES INCLUDED ARE BUENA VISTA CALHOUN CHEROKEE CLAY DICKINSON EMMET HANCOCK HUMBOLDT IDA KOSSUTH O'BRIEN PALO ALTO POCAHONTAS SAC WINNEBAGO WOODBURY WORTH MNC013-039-043-047-091-099-109-147-161-180140- MN . MINNESOTA COUNTIES INCLUDED ARE BLUE EARTH DODGE FARIBAULT FREEBORN MARTIN MOWER OLMSTED STEELE WASECA Read more

WW 0140 Status Updates
STATUS REPORT ON WW 140 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNW SUX TO 45 WSW SPW TO 20 WNW FRM TO 25 NNE MKT TO 25 NNE EAU AND 20 NNW SUX TO 40 WSW SPW TO 20 WNW FRM TO 10 NW MKT TO 25 NNW LSE. ..WENDT..04/18/25 ATTN...WFO...FSD...DMX...MPX...ARX... STATUS REPORT FOR WS 140 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC021-025-035-041-059-063-081-091-093-109-141-147-151-161-189- 193-195-180140- IA . IOWA COUNTIES INCLUDED ARE BUENA VISTA CALHOUN CHEROKEE CLAY DICKINSON EMMET HANCOCK HUMBOLDT IDA KOSSUTH O'BRIEN PALO ALTO POCAHONTAS SAC WINNEBAGO WOODBURY WORTH MNC013-039-043-047-091-099-109-147-161-180140- MN . MINNESOTA COUNTIES INCLUDED ARE BLUE EARTH DODGE FARIBAULT FREEBORN MARTIN MOWER OLMSTED STEELE WASECA Read more

WW 0140 Status Updates
STATUS REPORT ON WW 140 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NNW SUX TO 45 WSW SPW TO 20 WNW FRM TO 25 NNE MKT TO 25 NNE EAU AND 20 NNW SUX TO 40 WSW SPW TO 20 WNW FRM TO 10 NW MKT TO 25 NNW LSE. ..WENDT..04/18/25 ATTN...WFO...FSD...DMX...MPX...ARX... STATUS REPORT FOR WS 140 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC021-025-035-041-059-063-081-091-093-109-141-147-151-161-189- 193-195-180140- IA . IOWA COUNTIES INCLUDED ARE BUENA VISTA CALHOUN CHEROKEE CLAY DICKINSON EMMET HANCOCK HUMBOLDT IDA KOSSUTH O'BRIEN PALO ALTO POCAHONTAS SAC WINNEBAGO WOODBURY WORTH MNC013-039-043-047-091-099-109-147-161-180140- MN . MINNESOTA COUNTIES INCLUDED ARE BLUE EARTH DODGE FARIBAULT FREEBORN MARTIN MOWER OLMSTED STEELE WASECA Read more

WW 140 SEVERE TSTM IA MN NE WI 172045Z - 180300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 140 NWS Storm Prediction Center Norman OK 345 PM CDT Thu Apr 17 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest and Northern Iowa Southern and Southeast Minnesota Far Northeast Nebraska West-Central Wisconsin * Effective this Thursday afternoon and evening from 345 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Scattered thunderstorms are forecast to develop and intensify through the early evening across the Watch area. The stronger storms will be capable of a threat for large to very large hail (1 to 2 inches in diameter) and damaging gusts. Upscale growth into a linear cluster is possible this evening across southern Minnesota as this activity moves east towards the Mississippi River. The severe thunderstorm watch area is approximately along and 65 statute miles east and west of a line from 25 miles northeast of Minneapolis MN to 30 miles south southwest of Storm Lake IA. 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 25030. ...Smith Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0734 PM CDT Thu Apr 17 2025 Valid 180100Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EXTREME EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms will continue early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...01z Update... Water-vapor imagery suggests a weak short-wave trough is located over western NE, extending into northwest KS. Later tonight an 80kt 500mb speed max will translate across KS toward southeast NE, and this will encourage a marked increase in the LLJ across KS into northwest MO by 06z. Latest radar data depicts isolated-scattered severe supercells near the MO River from eastern NE into western IA. This activity will spread east, aided in part by the aforementioned LLJ. With time, storm inflow will gradually lift as the boundary layer decouples, and storms will become more elevated. For the next few hours very large hail remains possible, along with a risk for tornadoes, and wind. As the storms become elevated hail will become the most likely concern. ..Darrow.. 04/18/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0734 PM CDT Thu Apr 17 2025 Valid 180100Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EXTREME EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms will continue early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...01z Update... Water-vapor imagery suggests a weak short-wave trough is located over western NE, extending into northwest KS. Later tonight an 80kt 500mb speed max will translate across KS toward southeast NE, and this will encourage a marked increase in the LLJ across KS into northwest MO by 06z. Latest radar data depicts isolated-scattered severe supercells near the MO River from eastern NE into western IA. This activity will spread east, aided in part by the aforementioned LLJ. With time, storm inflow will gradually lift as the boundary layer decouples, and storms will become more elevated. For the next few hours very large hail remains possible, along with a risk for tornadoes, and wind. As the storms become elevated hail will become the most likely concern. ..Darrow.. 04/18/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0734 PM CDT Thu Apr 17 2025 Valid 180100Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EXTREME EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms will continue early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...01z Update... Water-vapor imagery suggests a weak short-wave trough is located over western NE, extending into northwest KS. Later tonight an 80kt 500mb speed max will translate across KS toward southeast NE, and this will encourage a marked increase in the LLJ across KS into northwest MO by 06z. Latest radar data depicts isolated-scattered severe supercells near the MO River from eastern NE into western IA. This activity will spread east, aided in part by the aforementioned LLJ. With time, storm inflow will gradually lift as the boundary layer decouples, and storms will become more elevated. For the next few hours very large hail remains possible, along with a risk for tornadoes, and wind. As the storms become elevated hail will become the most likely concern. ..Darrow.. 04/18/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0734 PM CDT Thu Apr 17 2025 Valid 180100Z - 181200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EXTREME EASTERN NEBRASKA INTO WESTERN AND CENTRAL IOWA... ...SUMMARY... Isolated to scattered severe thunderstorms will continue early tonight from eastern Nebraska into western and central Iowa. Very large hail to 3 inches in diameter or greater, isolated severe gusts of 60-70 mph, and a couple of tornadoes will all be possible. ...01z Update... Water-vapor imagery suggests a weak short-wave trough is located over western NE, extending into northwest KS. Later tonight an 80kt 500mb speed max will translate across KS toward southeast NE, and this will encourage a marked increase in the LLJ across KS into northwest MO by 06z. Latest radar data depicts isolated-scattered severe supercells near the MO River from eastern NE into western IA. This activity will spread east, aided in part by the aforementioned LLJ. With time, storm inflow will gradually lift as the boundary layer decouples, and storms will become more elevated. For the next few hours very large hail remains possible, along with a risk for tornadoes, and wind. As the storms become elevated hail will become the most likely concern. ..Darrow.. 04/18/2025 Read more