Storm Prediction Center

WW 128 SEVERE TSTM MN WI 171420Z - 172200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 128 NWS Storm Prediction Center Norman OK 920 AM CDT Fri Apr 17 2026 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of East-Central and Far Southeast Minnesota Northwest and North-Central Wisconsin * Effective this Friday morning and afternoon from 920 AM until 500 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Isolated damaging wind gusts to 70 mph possible SUMMARY...Ongoing line of thunderstorms over southeast MN is forecast to continue northeastward. The overall environment ahead of this line is expected to become more supportive of strong to severe storms with time. Additional thunderstorm development is anticipated as well. Large hail is the primary severe risk, although isolated strong gusts are possible as well. The severe thunderstorm watch area is approximately along and 75 statute miles east and west of a line from 105 miles north of Eau Claire WI to 10 miles east of La Crosse WI. 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. && 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 500. Mean storm motion vector 24030. ...Mosier Read more

MD 0476 CONCERNING TORNADO WATCH 129... FOR CENTRAL/EASTERN IOWA INTO SOUTHEASTERN MINNESOTA
Mesoscale Discussion 0476 NWS Storm Prediction Center Norman OK 0249 PM CDT Fri Apr 17 2026 Areas affected...central/eastern Iowa into southeastern Minnesota Concerning...Tornado Watch 129... Valid 171949Z - 172145Z The severe weather threat for Tornado Watch 129 continues. SUMMARY...Threat for large to very large hail, wind, and tornadoes continues within WW129. DISCUSSION...Thunderstorm activity has increased along the cold front in central Iowa into southeastern Minnesota. Mode is rather mixed, with clusters and more semi-discrete supercells along and ahead of the front. Reports of large hail 1-1.75 inches in diameter and a tornado were reported near Olmstead, MN. The threat for large hail, tornadoes, and damaging wind will continue over the next several hours. Daytime heating and warm air advection has yielded MLCAPE around 2000-3000 J/kg. The 18z RAOB from DVN shows this well, with analyzed 2100 J/kg MLCAPE, steep low to mid-level lapse rates and an enlarged clock-wise low-level hodograph. As the front moves eastward and mode shifts to become more linear, the main threats will shift to damaging wind and continued potential for line embedded tornadoes. With any supercells that can maintain ahead of the line (particularly from eastern Iowa into southern Wisconsin), large hail, and strong tornado potential will continue. ..Thornton.. 04/17/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...MPX...DMX... LAT...LON 44689181 44719166 44089098 43199071 42469086 41279180 40809269 40839376 41469364 43379278 44239250 44559207 44689181 MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN Read more

MD 0479 CONCERNING TORNADO WATCH 130... FOR PORTIONS OF NORTHEASTERN KANSAS...NORTHWESTERN MISSOURI...AND EXTREME SOUTHERN IOWA
Mesoscale Discussion 0479 NWS Storm Prediction Center Norman OK 0331 PM CDT Fri Apr 17 2026 Areas affected...portions of northeastern Kansas...northwestern Missouri...and extreme southern Iowa Concerning...Tornado Watch 130... Valid 172031Z - 172200Z The severe weather threat for Tornado Watch 130 continues. SUMMARY...Tornado threat is increasing across portions of Tornado Watch 130. DISCUSSION...Two lines of supercells have become more well established over the past hour from southeastern Kansas into southern Iowa, with strengthening low-level rotation noted with some storms and a tornado recently reported in Atchison County, Kansas. The environment near/ahead of these storms is within a zone of favorable low-level moisture and increasing low-level shear, with the latest mesoanalysis and EAX/INX VAD profiles indicating around 100 m2/s2 0-500 m SRH and effective STP of 2+. With a coincident favorable thermodynamic environment, the potential for tornadoes (and perhaps a strong tornado) is increasing. ..Chalmers.. 04/17/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...DMX...EAX...TOP...ICT... LAT...LON 38839329 38259393 37219490 37019550 37009662 37529695 38019688 38489648 39019594 40289451 40669396 40769333 40639276 40459252 40199239 39789242 39299291 38839329 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...75-90 MPH MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN Read more

WW 0130 Status Updates
STATUS REPORT ON WW 130 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 W AVK TO AVK TO 20 WSW EMP TO 10 NE TOP TO 35 NE STJ TO 25 E LWD. ..WENDT..04/17/26 ATTN...WFO...ICT...TOP...EAX...DDC...SGF...OUN...TSA... STATUS REPORT FOR WT 130 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC001-003-011-015-017-019-021-031-035-037-045-049-059-073-077- 091-099-103-107-111-121-125-133-139-173-191-205-207-209- 172240- KS . KANSAS COUNTIES INCLUDED ARE ALLEN ANDERSON BOURBON BUTLER CHASE CHAUTAUQUA CHEROKEE COFFEY COWLEY CRAWFORD DOUGLAS ELK FRANKLIN GREENWOOD HARPER JOHNSON LABETTE LEAVENWORTH LINN LYON MIAMI MONTGOMERY NEOSHO OSAGE SEDGWICK SUMNER WILSON WOODSON WYANDOTTE MOC001-011-013-021-025-033-037-041-047-049-053-061-063-079-081- 083-089-095-101-107-115-117-121-129-159-165-171-175-177-185-195- 197-211-217-172240- MO . MISSOURI COUNTIES INCLUDED ARE Read more

WW 0131 Status Updates
STATUS REPORT ON WW 131 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..WENDT..04/17/26 ATTN...WFO...LSX...ILX...LOT... STATUS REPORT FOR WT 131 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-005-009-013-017-021-027-031-039-043-051-053-057-061-063- 075-083-089-091-093-095-097-105-107-113-115-117-119-121-123-125- 129-133-135-137-143-149-163-167-169-171-173-175-179-189-197-203- 172240- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BOND BROWN CALHOUN CASS CHRISTIAN CLINTON COOK DE WITT DUPAGE FAYETTE FORD FULTON GREENE GRUNDY IROQUOIS JERSEY KANE KANKAKEE KENDALL KNOX LAKE LIVINGSTON LOGAN MCLEAN MACON MACOUPIN MADISON MARION MARSHALL MASON MENARD MONROE MONTGOMERY MORGAN PEORIA PIKE ST. CLAIR SANGAMON SCHUYLER SCOTT SHELBY STARK TAZEWELL WASHINGTON WILL WOODFORD Read more

WW 0129 Status Updates
STATUS REPORT ON WW 129 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 W LWD TO 30 NNE OXV TO 30 NNE RST TO 40 W EAU. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0476 ..THORNTON..04/17/26 ATTN...WFO...ARX...DMX...DVN...LOT...MPX...GRB...MKX... STATUS REPORT FOR WT 129 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-011-015-037-067-071-073-085-099-103-109-111-131-141-155- 161-177-187-195-201-172140- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE BUREAU CARROLL DE KALB HANCOCK HENDERSON HENRY JO DAVIESS LA SALLE LEE MCDONOUGH MCHENRY MERCER OGLE PUTNAM ROCK ISLAND STEPHENSON WARREN WHITESIDE WINNEBAGO IAC005-007-011-013-017-019-031-037-039-043-045-051-053-055-057- 061-065-075-087-089-095-097-099-101-103-105-107-111-113-115-117- 123-125-135-139-157-163-171-177-179-183-185-191-172140- IA . IOWA COUNTIES INCLUDED ARE ALLAMAKEE APPANOOSE BENTON Read more

WW 0128 Status Updates
STATUS REPORT ON WW 128 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SE MSP TO 20 SSW DLH. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0478 ..THORNTON..04/17/26 ATTN...WFO...MPX...ARX...DLH...GRB... STATUS REPORT FOR WS 128 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS WIC003-005-007-013-017-031-033-051-069-085-091-095-099-107-109- 113-119-125-129-172140- WI . WISCONSIN COUNTIES INCLUDED ARE ASHLAND BARRON BAYFIELD BURNETT CHIPPEWA DOUGLAS DUNN IRON LINCOLN ONEIDA PEPIN POLK PRICE RUSK ST. CROIX SAWYER TAYLOR VILAS WASHBURN 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

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Apr 17 2026 Valid 172000Z - 181200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO WEST-CENTRAL MISSOURI... ...SUMMARY... Numerous severe thunderstorms are likely this afternoon into tonight across parts of the Upper Midwest southward across the lower Missouri Valley and central/southern Great Plains. Initially this may be accompanied by a risk for large to giant hail and a few strong tornadoes, before severe wind gusts of 60 to 90 mph become the most prominent hazard by this evening. ...20Z Update... Severe probabilities have been adjusted to account for progression of the cold front this afternoon. The remainder of the forecast is unchanged. See MD 475 for short-term details of evolving tornado risk along the Illinois/Wisconsin border. ..Wendt.. 04/17/2026 .PREV DISCUSSION... /ISSUED 1203 PM CDT Fri Apr 17 2026/ ...Synopsis... Recent surface analysis places a low over south-central MN, with a cold front extending southwestward to another low over central KS. A warm front also extends southwestward from the MN low through far southwest MN and far northern IL into central IN. This warm front is demarcated well by the 56 deg F isodrosotherm. Farther south, a dryline extends from the triple point KS low back southwestward through the TX Panhandle and into far southeast NM. A broad, moist warm sector exists to the east of the cold front and dryline, characterized largely by dewpoints in the low to mid 60s. A well-defined shortwave trough is apparent on satellite imagery, extending from southern Saskatchewan back southwestward into the eastern Great Basin. This wave is forecast to continue eastward, with a attendant increase in the mid-level flow across much of the Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting with the warm sector to support numerous strong to severe thunderstorms from parts of the Upper Midwest southward across the lower Missouri Valley into southern Plains. ...Upper/Mid MS Valley... Moderate to strong low-level moisture advection is expected across the Upper MS Valley today as the surface low mentioned in the synopsis progresses northeastward, with an attendant northward shift of the warm front as well. The risk across this region may evolve in several phases, beginning with the elevated thunderstorms currently ongoing across northwest WI. This storms will likely continue northeastward, posing a risk for severe hail and isolated damaging gusts. Additional development is possible northwest of this activity along the occluded front, with some hail possible here as well. Farther south, the northeastward advecting low-level moisture coupled with strong heating and steep lapse rates will result in a strongly unstable airmass along and just south of the warm front by the early afternoon. Storm initiation is anticipated within this open warm sector by early afternoon, forced by a mix of warm-air advection, low-level confluence, and subtly increasing large-scale ascent. This activity should be ahead of the front and initially discrete. The overall parameter space will be characterized by strong to very strong buoyancy, moderate deep-layer vertical shear, and strong low-level helicity. Supercells capable of all hazards are expected, including large to very large (i.e. 3"+ hail), strong to intense tornadoes, and severe wind gusts. Storm interactions are expected to strongly influence the tornado risk, with the initially discrete mode likely becoming messy quickly. Farther west, other storms are likely to evolve quickly along the front, developing into a band of severe thunderstorms that will push east coincident with the front. Damaging wind gusts will tend to become more prevalent during the evening with linear storm modes. Some tornado risk may continue into the evening as maturing bands of storms yield a threat for bowing segments and embedded mesovortices, before this activity gradually diminishes late as it moves east into IN/Lower MI late. ...KS/OK/MO... A very unstable airmass is expected to develop along and ahead of the triple point over south-central KS an associated cold front and dryline. Strong low-level convergence will likely lead to initial storm development near the triple point. This initial activity will be supercellular and capable of very large to giant hail (over 3-3.5" in diameter). Highest coverage of very large hail is expected over from far northwest OK into south-central KS. Strong downdrafts (60 to 80 mph) are possible as well. With a largely boundary-parallel orientation to the deep-layer shear, the tornado risk appears relatively lower. However, given the supercell mode and potential interactions with outflow, a low-probability tornado risk remains. A more north-south configuration to the dryline supports a conditional tornado risk into far northwest TX. With time, upscale growth and the development of a forward-propagating MCS is anticipated across central and eastern KS. Very strong gusts (80+ mph) are possible with this MCS. Additionally, some QLCS tornado risk will exist within this line as long as it stays ahead of the surging cold front. The front will continue sweeping southeastward, with storms along this boundary yielding a risk for wind/hail. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Apr 17 2026 Valid 172000Z - 181200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO WEST-CENTRAL MISSOURI... ...SUMMARY... Numerous severe thunderstorms are likely this afternoon into tonight across parts of the Upper Midwest southward across the lower Missouri Valley and central/southern Great Plains. Initially this may be accompanied by a risk for large to giant hail and a few strong tornadoes, before severe wind gusts of 60 to 90 mph become the most prominent hazard by this evening. ...20Z Update... Severe probabilities have been adjusted to account for progression of the cold front this afternoon. The remainder of the forecast is unchanged. See MD 475 for short-term details of evolving tornado risk along the Illinois/Wisconsin border. ..Wendt.. 04/17/2026 .PREV DISCUSSION... /ISSUED 1203 PM CDT Fri Apr 17 2026/ ...Synopsis... Recent surface analysis places a low over south-central MN, with a cold front extending southwestward to another low over central KS. A warm front also extends southwestward from the MN low through far southwest MN and far northern IL into central IN. This warm front is demarcated well by the 56 deg F isodrosotherm. Farther south, a dryline extends from the triple point KS low back southwestward through the TX Panhandle and into far southeast NM. A broad, moist warm sector exists to the east of the cold front and dryline, characterized largely by dewpoints in the low to mid 60s. A well-defined shortwave trough is apparent on satellite imagery, extending from southern Saskatchewan back southwestward into the eastern Great Basin. This wave is forecast to continue eastward, with a attendant increase in the mid-level flow across much of the Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting with the warm sector to support numerous strong to severe thunderstorms from parts of the Upper Midwest southward across the lower Missouri Valley into southern Plains. ...Upper/Mid MS Valley... Moderate to strong low-level moisture advection is expected across the Upper MS Valley today as the surface low mentioned in the synopsis progresses northeastward, with an attendant northward shift of the warm front as well. The risk across this region may evolve in several phases, beginning with the elevated thunderstorms currently ongoing across northwest WI. This storms will likely continue northeastward, posing a risk for severe hail and isolated damaging gusts. Additional development is possible northwest of this activity along the occluded front, with some hail possible here as well. Farther south, the northeastward advecting low-level moisture coupled with strong heating and steep lapse rates will result in a strongly unstable airmass along and just south of the warm front by the early afternoon. Storm initiation is anticipated within this open warm sector by early afternoon, forced by a mix of warm-air advection, low-level confluence, and subtly increasing large-scale ascent. This activity should be ahead of the front and initially discrete. The overall parameter space will be characterized by strong to very strong buoyancy, moderate deep-layer vertical shear, and strong low-level helicity. Supercells capable of all hazards are expected, including large to very large (i.e. 3"+ hail), strong to intense tornadoes, and severe wind gusts. Storm interactions are expected to strongly influence the tornado risk, with the initially discrete mode likely becoming messy quickly. Farther west, other storms are likely to evolve quickly along the front, developing into a band of severe thunderstorms that will push east coincident with the front. Damaging wind gusts will tend to become more prevalent during the evening with linear storm modes. Some tornado risk may continue into the evening as maturing bands of storms yield a threat for bowing segments and embedded mesovortices, before this activity gradually diminishes late as it moves east into IN/Lower MI late. ...KS/OK/MO... A very unstable airmass is expected to develop along and ahead of the triple point over south-central KS an associated cold front and dryline. Strong low-level convergence will likely lead to initial storm development near the triple point. This initial activity will be supercellular and capable of very large to giant hail (over 3-3.5" in diameter). Highest coverage of very large hail is expected over from far northwest OK into south-central KS. Strong downdrafts (60 to 80 mph) are possible as well. With a largely boundary-parallel orientation to the deep-layer shear, the tornado risk appears relatively lower. However, given the supercell mode and potential interactions with outflow, a low-probability tornado risk remains. A more north-south configuration to the dryline supports a conditional tornado risk into far northwest TX. With time, upscale growth and the development of a forward-propagating MCS is anticipated across central and eastern KS. Very strong gusts (80+ mph) are possible with this MCS. Additionally, some QLCS tornado risk will exist within this line as long as it stays ahead of the surging cold front. The front will continue sweeping southeastward, with storms along this boundary yielding a risk for wind/hail. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Fri Apr 17 2026 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Sunday. ...Discussion... An amplified large-scale trough will move eastward from the Great Lakes to the Northeast on Sunday, while a related cold front moves off the Eastern Seaboard. Despite poor deep-layer lapse rates, a narrow corridor of diurnal heating amid lower/middle 60s dewpoints (higher over the FL Peninsula) ahead of the front should support isolated thunderstorms from the coastal Carolinas southward across parts of the FL Peninsula. Weak/narrow buoyancy profiles will limit thunderstorm intensity and the severe risk. ..Weinman.. 04/17/2026 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 PM CDT Fri Apr 17 2026 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Sunday. ...Discussion... An amplified large-scale trough will move eastward from the Great Lakes to the Northeast on Sunday, while a related cold front moves off the Eastern Seaboard. Despite poor deep-layer lapse rates, a narrow corridor of diurnal heating amid lower/middle 60s dewpoints (higher over the FL Peninsula) ahead of the front should support isolated thunderstorms from the coastal Carolinas southward across parts of the FL Peninsula. Weak/narrow buoyancy profiles will limit thunderstorm intensity and the severe risk. ..Weinman.. 04/17/2026 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 PM CDT Fri Apr 17 2026 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN AND CENTRAL NEBRASKA... ...Southern/Central Plains A Critical area was added for portions of western/central Nebraska as west-northwest sustained winds of 20-25 mph amid minimum RH of 15-20% are expected. The Critical area may need to be expanded in Nebraska if ensemble high-resolution forecast guidance continues to trend towards higher probabilities for critical RH. The Elevated area was expanded across Nebraska, central Kansas, southern South Dakota, eastern Colorado, western Oklahoma, and west Texas amid dry and breezy post-frontal conditions, with recent/forecast precipitation helping to delineate the expansion of the Elevated area. ...Southeast/Mid-Atlantic... The Elevated area in the Southeast and Mid-Atlantic was also expanded slightly, with pre-frontal elevated winds/RH appearing more likely along/east of the Appalachians in portions of Virginia, West Virginia, Maryland, and Pennsylvania. Thunderstorms are expected along/ahead of the approaching cold front in the southern/central Appalachians tomorrow late afternoon into tomorrow night. While not a conducive or typical dry thunderstorm environment, the expected lightning with 50%+ probability of receiving less than 0.25" of rainfall on eastern slopes of the Appalachians onto the Piedmont Plateau could result in ignitions. Given the following dry and breezy post-frontal conditions on Day 3/Sunday - Day 4/Monday, there is concern for increased spread potential of any existing and new ignitions. ..Nauslar.. 04/17/2026 .PREV DISCUSSION... /ISSUED 0108 AM CDT Fri Apr 17 2026/ ...Synopsis... An amplified upper trough will move towards the upper Great Lakes and Ohio Valley as temporary upper ridging builds over the West. Enhanced southwest winds ahead of an eastward progressing cold front will pose an Elevated fire weather threat across parts of the Southeast and Mid-Atlantic. In the wake of the aforementioned upper trough, a post-frontal dry airmass and northerly flow will promote Elevated fire weather conditions across portions of the central Plains. ...Central Plains... Within a post-frontal environment, northwesterly winds of 15-20 mph and RH of 15-25 percent over dry fuels will pose an Elevated fire weather threat for portions of central NE, eastern CO, and western KS on Saturday. However, the areal extent of fire weather highlights may change as forecast precipitation (and perhaps some snowfall) on Day 1/Friday may provide some relief to fuel conditions. ...Southeast and Mid-Atlantic... Increasing southwest flow ahead of an advancing cold front coupled with the lack of Gulf moisture return and resultant low RH are expected to promote an Elevated fire weather threat across much of the Southeast into the Mid-Atlantic. At peak heating, widespread RH of less than 30 percent will combine with southwesterly winds of 10-15 mph atop receptive fuels. A prolonged period of above normal temperatures and lack of appreciable rainfall continues to exacerbate fuel conditions across this region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 PM CDT Fri Apr 17 2026 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN AND CENTRAL NEBRASKA... ...Southern/Central Plains A Critical area was added for portions of western/central Nebraska as west-northwest sustained winds of 20-25 mph amid minimum RH of 15-20% are expected. The Critical area may need to be expanded in Nebraska if ensemble high-resolution forecast guidance continues to trend towards higher probabilities for critical RH. The Elevated area was expanded across Nebraska, central Kansas, southern South Dakota, eastern Colorado, western Oklahoma, and west Texas amid dry and breezy post-frontal conditions, with recent/forecast precipitation helping to delineate the expansion of the Elevated area. ...Southeast/Mid-Atlantic... The Elevated area in the Southeast and Mid-Atlantic was also expanded slightly, with pre-frontal elevated winds/RH appearing more likely along/east of the Appalachians in portions of Virginia, West Virginia, Maryland, and Pennsylvania. Thunderstorms are expected along/ahead of the approaching cold front in the southern/central Appalachians tomorrow late afternoon into tomorrow night. While not a conducive or typical dry thunderstorm environment, the expected lightning with 50%+ probability of receiving less than 0.25" of rainfall on eastern slopes of the Appalachians onto the Piedmont Plateau could result in ignitions. Given the following dry and breezy post-frontal conditions on Day 3/Sunday - Day 4/Monday, there is concern for increased spread potential of any existing and new ignitions. ..Nauslar.. 04/17/2026 .PREV DISCUSSION... /ISSUED 0108 AM CDT Fri Apr 17 2026/ ...Synopsis... An amplified upper trough will move towards the upper Great Lakes and Ohio Valley as temporary upper ridging builds over the West. Enhanced southwest winds ahead of an eastward progressing cold front will pose an Elevated fire weather threat across parts of the Southeast and Mid-Atlantic. In the wake of the aforementioned upper trough, a post-frontal dry airmass and northerly flow will promote Elevated fire weather conditions across portions of the central Plains. ...Central Plains... Within a post-frontal environment, northwesterly winds of 15-20 mph and RH of 15-25 percent over dry fuels will pose an Elevated fire weather threat for portions of central NE, eastern CO, and western KS on Saturday. However, the areal extent of fire weather highlights may change as forecast precipitation (and perhaps some snowfall) on Day 1/Friday may provide some relief to fuel conditions. ...Southeast and Mid-Atlantic... Increasing southwest flow ahead of an advancing cold front coupled with the lack of Gulf moisture return and resultant low RH are expected to promote an Elevated fire weather threat across much of the Southeast into the Mid-Atlantic. At peak heating, widespread RH of less than 30 percent will combine with southwesterly winds of 10-15 mph atop receptive fuels. A prolonged period of above normal temperatures and lack of appreciable rainfall continues to exacerbate fuel conditions across this region. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0473 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR NORTHEASTERN IOWA...SOUTHEASTERN MINNESOTA...SOUTHERN/WESTERN WISCONSIN
Mesoscale Discussion 0473 NWS Storm Prediction Center Norman OK 1148 AM CDT Fri Apr 17 2026 Areas affected...northeastern Iowa...southeastern Minnesota...southern/western Wisconsin Concerning...Severe potential...Tornado Watch likely Valid 171648Z - 171915Z Probability of Watch Issuance...80 percent SUMMARY...Increasing potential for supercells capable of all hazards. DISCUSSION...Visible satellite trends show two areas of cumulus increasing near the cold front/dry line in north-central Iowa/southern Minnesota and further east in a confluence band in northeastern Iowa. A few attempts are note on radar near the front over the last 30 minutes. Across the open warm sector in central/eastern Iowa into southern WI/northern Illinois, strong warm air advection within the 40-45 kt southerly LLJ is ongoing with moderate to strong MLCAPE and strong deep layer shear profiles supportive of supercells. Uncertainty remains in what the exact evolution of storms will be. Two scenarios are possible: initial supercell development in eastern Iowa ahead of the front and supercell development along the cold front. Confidence is highest that there will be development further west along the cold front, which will initially be supercelluar given, the favorable profiles. The time period for more discrete supercells may be cut short across this region as the cold front undercuts convection. Nonetheless, initially large to very large hail will be possible with an increasing tornado threat as convection matures. As more clustering/upscale growth occurs, threat to damaging winds will increase with a line embedded tornado threat continuing through the afternoon/evening. Further east, isolated supercells may develop within the open warm sector across northeastern Iowa nearer to the warm front. These would also be capable of large to very large hail. Should they persist, there would also be enhanced potential for strong tornadoes given the SRH rich environment. A Tornado watch will likely be needed in the next 1-2 hours. ..Thornton/Mosier.. 04/17/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...LOT...MKX...DVN...ARX...MPX...DMX... LAT...LON 44529149 44128969 44028899 43828843 43318829 42138908 42058925 41818999 42049121 42329258 42619354 43299446 43999375 44629338 45079327 45179313 44919236 44529149 MOST PROBABLE PEAK TORNADO INTENSITY...140-170 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN Read more

MD 0474 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF THE SOUTHERN/CENTRAL GREAT PLAINS INTO THE MID-MISSOURI VALLEY
Mesoscale Discussion 0474 NWS Storm Prediction Center Norman OK 1242 PM CDT Fri Apr 17 2026 Areas affected...portions of the southern/central Great Plains into the mid-Missouri Valley Concerning...Severe potential...Watch likely Valid 171742Z - 172015Z Probability of Watch Issuance...95 percent SUMMARY...Numerous severe thunderstorms are expected to form along/ahead of a cold front and dryline from northern Missouri southwestward into northwestern Oklahoma this afternoon. Storms will pose a threat for all hazards, including hail to 3-3.5+ inches in diameter, very strong wind gusts of 60-80+ mph, and a couple of tornadoes (perhaps strong). Watch issuance will be needed in the next 1-2 hours. DISCUSSION...Latest mesoanalysis depicts a strongly unstable air mass in place ahead of a triple point over northwestern Oklahoma and the associated cold front/dryline. Temperatures in the upper-70s F and dewpoints in the mid/upper-60s are contributing to strong instability of 2000-3000+ J/kg MLCAPE across the region per latest mesoanalysis. Low-level convergence is forecast to lead to convection initiation near the triple point and along the cold front/prefrontal confluence zone through the afternoon. Strong southwesterly flow (50+ kts at 4-5 km AGL per regional VWPs) is contributing to effective bulk shear of 40-50 kts (locally greater near the triple point), which will support supercells with initial storm formation. Steep mid-level lapse rates (as sampled by the 12z OUN/TOP/SGF soundings and recent ACARS profiles), elongated hodographs, and ample buoyancy within the hail growth zone will support the potential for hail of 3-3.5+ inches in diameter. Strong downdrafts (with wind gusts up to 60-80 mph) are also possible given the presence of some drier mid-level air. The tornado threat remains more uncertain as deep-layer flow is largely oriented parallel to the cold front, which may yield complex storm mode/interactions. Given the potential for supercellular mode and storm/outflow interactions, at least some potential for a couple of tornadoes (perhaps strong) appears to exist, however. This appears most likely with any supercell that is able to remain more discrete into the evening hours when a strengthening nocturnal low-level jet will yield increasingly curved low-level hodographs. Trends will continue to be monitored, and a tornado watch will be needed within the next 1-2 hours to cover these threats. With time, the development of a forward-propagating MCS is anticipated across much of this area, with an accompanying transition towards severe wind gusts (80+ mph wind gusts possible) and perhaps embedded tornadoes as the primary threats. ..Chalmers/Mosier.. 04/17/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX...TSA...OAX...TOP...ICT...OUN...DDC... LAT...LON 36559959 37359896 38879741 40089628 40419548 40519443 40279381 39679370 38659397 37659462 36669558 35639699 35079813 34999904 35509967 36559959 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...75-90 MPH MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN Read more

WW 0130 Status Updates
STATUS FOR WATCH 0130 HAS NOT BEEN ISSUED YET Read more

WW 0128 Status Updates
STATUS REPORT ON WW 128 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 N MSP TO 15 SSE DLH. ..THORNTON..04/17/26 ATTN...WFO...MPX...ARX...DLH...GRB... STATUS REPORT FOR WS 128 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MNC163-171940- MN . MINNESOTA COUNTIES INCLUDED ARE WASHINGTON WIC003-005-007-013-017-031-033-051-069-085-091-095-099-107-109- 113-119-125-129-171940- WI . WISCONSIN COUNTIES INCLUDED ARE ASHLAND BARRON BAYFIELD BURNETT CHIPPEWA DOUGLAS DUNN IRON LINCOLN ONEIDA PEPIN POLK PRICE RUSK ST. CROIX SAWYER TAYLOR VILAS WASHBURN THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL Read more

WW 0129 Status Updates
STATUS FOR WATCH 0129 HAS NOT BEEN ISSUED YET Read more

WW 0129 Status Updates
STATUS FOR WATCH 0129 HAS NOT BEEN ISSUED YET Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Fri Apr 17 2026 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER OHIO VALLEY AND CENTRAL APPALACHIANS... ...SUMMARY... Scattered strong to severe thunderstorms capable of damaging winds and hail will be possible on Saturday across the upper Ohio Valley and central Appalachians. Isolated severe hail is also possible across parts of central Texas. ...Synopsis... An amplified midlevel trough will advance eastward from the upper MS Valley to the Great Lakes/OH Valley on Saturday. At the same time, a cold front extending from lower MI south-southwestward into south-central TX will move east-southeastward across the OH, TN, and lower MS Valley during the day. Remnant showers and thunderstorms will be ongoing along the eastward-moving front at the start of the period, though this lingering/early-morning activity is generally expected to be sub-severe. ...Upper OH Valley and Central Appalachians... As the cold front continues eastward into the upper OH Valley and central Appalachians into the afternoon, diurnal heating amid a narrow corridor of upper 50s to lower 60s dewpoints will contribute to marginal surface-based destabilization immediately ahead of the front. This, combined with around 40-50 kt of effective shear oriented oblique to the front, should favor a mix of organized clusters and perhaps a couple supercell structures -- posing a risk of scattered damaging wind gusts and isolated severe hail. Additionally, a remnant 30-40 kt south-southwesterly low-level jet will yield modest low-level shear/hodograph curvature, and a tornado or two will be possible with the more organized storms. ...Central TX... High-resolution guidance is in relatively good agreement, depicting elevated thunderstorms evolving behind the cold front during the morning and early afternoon. Steep midlevel lapse rates atop the frontal surface and elongated/straight hodographs (around 50 kt of effective shear) could lead to isolated severe hail with any elevated supercells that evolve. ...Lower MS and TN Valleys... A couple strong storms will also be possible immediately ahead of the front as it impinges on the lower MS and TN Valleys during the afternoon, given around 40 kt of deep-layer shear and a weakly unstable air mass. However, displacement from the deep-layer forcing for ascent accompanying the trough, and skinny CAPE profiles, limits confidence in the severe risk here -- precluding probabilities at this time. ..Weinman.. 04/17/2026 Read more