Severe Storms

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1228 AM CDT Mon Apr 21 2025 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER OHIO VALLEY AND CENTRAL GULF STATES... ...SUMMARY... A few strong storms are possible across the upper Ohio Valley and across portions of the central Gulf States. Gusty winds and marginally severe hail are the primary risks. ...Upper Ohio Valley... Mid-MS Valley short-wave trough is forecast to eject into the upper Great Lakes region by mid day as 70+kt 500mb speed max translates across northern IN into southern ON. 500mb wind fields will strengthen across the upper OH Valley in response to this feature as heights are suppressed ahead of the short wave. Latest model guidance suggests the associated cold front will surge into western OH/KY by 18z, subsequently advancing into western PA later in the evening. Modest boundary-layer heating should contribute to adequate buoyancy for robust updrafts, and scattered convection should develop ahead of the front as temperatures warm through the 70s. Gusty winds may accompany this activity, along with some risk for marginally severe hail. ...Central Gulf States... Synoptic front will trail across the TN Valley through the central Gulf States today serving as the focus for thunderstorms as convective temperatures are breached along this weakly-forced boundary. While 0-6km bulk shear should only be modest across this region, seasonally high PW values and MLCAPE in excess of 1500 J/kg suggest some risk for gusty winds and hail. Boundary-layer heating should prove instrumental in convective updraft strength today. ..Darrow/Squitieri.. 04/21/2025 Read more

MD 0509 CONCERNING TORNADO WATCH 157... FOR PORTIONS OF NORTHERN ILLINOIS
Mesoscale Discussion 0509 NWS Storm Prediction Center Norman OK 0954 PM CDT Sun Apr 20 2025 Areas affected...portions of northern Illinois Concerning...Tornado Watch 157... Valid 210254Z - 210430Z The severe weather threat for Tornado Watch 157 continues. SUMMARY...The severe threat continues across Tornado Watch 157. A couple of severe gusts are the main concern, though a tornado cannot be ruled out. DISCUSSION...A primary band of convection persists amid very strong forcing accompanying an approaching surface low and upper-level jet streak. Despite scant buoyancy, the latest LOT VAD shows a hodograph with impressive size and curvature, indicating strong low-level wind shear, driven by very strong flow just above the surface. While decreasing lightning trends suggest that storms are weakening, the intense low-level flow/shear suggests that damaging gusts may still occur wherever downward momentum transport may occur. A tornado also remains possible if a rotating updraft can ingest any remaining surface-based buoyancy. ..Squitieri.. 04/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...DVN... LAT...LON 40568839 40928885 41308911 41708931 41948922 41998888 41828838 41428803 40988774 40608769 40498805 40568839 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 0508 CONCERNING TORNADO WATCH 156... FOR EAST ARKANSAS...WEST TENNESSEE...FAR WEST KENTUCKY
Mesoscale Discussion 0508 NWS Storm Prediction Center Norman OK 0848 PM CDT Sun Apr 20 2025 Areas affected...east Arkansas...west Tennessee...far west Kentucky Concerning...Tornado Watch 156... Valid 210148Z - 210315Z The severe weather threat for Tornado Watch 156 continues. SUMMARY...Thunderstorms continue to move east across Arkansas. A tornado threat will continue through the evening before beginning to lessen toward midnight. Trends will be monitored for potential watch across far west Tennessee and Kentucky DISCUSSION...A broken line of thunderstorms, many exhibiting at least transient supercellular characteristics, will continue to move east this evening. Recent VAD wind profiles from NQA (Memphis 88D) show the low-level jet (as proxied by the 0-1 km shear value) has increased from around 15-20 knots three hours ago to nearly 35 knots at present. Additionally, the VAD profile shows considerable clockwise turning below three kilometers, with much of that in the lowest one kilometer AGL (0-1 km SRH of nearly 350 m2/s2). Presently, SPC mesoanalysis shows a significant reduction in instability across eastern Arkansas as compared to areas to the west. However, given the upstream airmass remains moist and the strength of the low-level jet, an axis of instability up to 1000 J/kg of MLCAPE should be maintained for at least another couple of hours. With time, large-scale ascent and the low-level jet across Arkansas should weaken as the main short-wave trough moves away from the area. The weakening low-level jet should result in increased difficulty maintaining low-level instability. This combined with increasing convective inhibition from the loss of diurnal heating should result in a decrease in convective intensity through the evening hours. However, storm-scale processes (e.g. mesoscyclones) will allow thunderstorms to persist for at least a couple of hours into the less favorable environment. Thus, western Tennessee and Kentucky will be monitored for the need of a tornado watch. ..Marsh.. 04/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...JAN...LZK...SHV... LAT...LON 36449104 36788802 33889070 33069332 36449104 MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

WW 0158 Status Updates
STATUS FOR WATCH 0158 HAS NOT BEEN ISSUED YET Read more

WW 0158 Status Updates
STATUS FOR WATCH 0158 HAS NOT BEEN ISSUED YET Read more

WW 0158 Status Updates
STATUS FOR WATCH 0158 HAS NOT BEEN ISSUED YET Read more

WW 0155 Status Updates
STATUS REPORT ON WW 155 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S POF TO 35 S FAM TO 25 WNW SLO. ..SQUITIERI..04/21/25 ATTN...WFO...DVN...LSX...PAH...ILX... STATUS REPORT FOR WT 155 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-011-021-027-039-051-055-077-081-087-113-115-121-123- 135-139-145-147-153-155-173-181-189-195-199-203-210340- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND BUREAU CHRISTIAN CLINTON DE WITT FAYETTE FRANKLIN JACKSON JEFFERSON JOHNSON MCLEAN MACON MARION MARSHALL MONTGOMERY MOULTRIE PERRY PIATT PULASKI PUTNAM SHELBY UNION WASHINGTON WHITESIDE WILLIAMSON WOODFORD KYC007-210340- KY . KENTUCKY COUNTIES INCLUDED ARE BALLARD Read more

WW 0155 Status Updates
STATUS REPORT ON WW 155 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S POF TO 35 S FAM TO 25 WNW SLO. ..SQUITIERI..04/21/25 ATTN...WFO...DVN...LSX...PAH...ILX... STATUS REPORT FOR WT 155 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-011-021-027-039-051-055-077-081-087-113-115-121-123- 135-139-145-147-153-155-173-181-189-195-199-203-210340- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND BUREAU CHRISTIAN CLINTON DE WITT FAYETTE FRANKLIN JACKSON JEFFERSON JOHNSON MCLEAN MACON MARION MARSHALL MONTGOMERY MOULTRIE PERRY PIATT PULASKI PUTNAM SHELBY UNION WASHINGTON WHITESIDE WILLIAMSON WOODFORD KYC007-210340- KY . KENTUCKY COUNTIES INCLUDED ARE BALLARD Read more

WW 0155 Status Updates
STATUS REPORT ON WW 155 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S POF TO 35 S FAM TO 25 WNW SLO. ..SQUITIERI..04/21/25 ATTN...WFO...DVN...LSX...PAH...ILX... STATUS REPORT FOR WT 155 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-011-021-027-039-051-055-077-081-087-113-115-121-123- 135-139-145-147-153-155-173-181-189-195-199-203-210340- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND BUREAU CHRISTIAN CLINTON DE WITT FAYETTE FRANKLIN JACKSON JEFFERSON JOHNSON MCLEAN MACON MARION MARSHALL MONTGOMERY MOULTRIE PERRY PIATT PULASKI PUTNAM SHELBY UNION WASHINGTON WHITESIDE WILLIAMSON WOODFORD KYC007-210340- KY . KENTUCKY COUNTIES INCLUDED ARE BALLARD Read more

WW 0155 Status Updates
STATUS REPORT ON WW 155 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S POF TO 35 S FAM TO 25 WNW SLO. ..SQUITIERI..04/21/25 ATTN...WFO...DVN...LSX...PAH...ILX... STATUS REPORT FOR WT 155 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-011-021-027-039-051-055-077-081-087-113-115-121-123- 135-139-145-147-153-155-173-181-189-195-199-203-210340- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND BUREAU CHRISTIAN CLINTON DE WITT FAYETTE FRANKLIN JACKSON JEFFERSON JOHNSON MCLEAN MACON MARION MARSHALL MONTGOMERY MOULTRIE PERRY PIATT PULASKI PUTNAM SHELBY UNION WASHINGTON WHITESIDE WILLIAMSON WOODFORD KYC007-210340- KY . KENTUCKY COUNTIES INCLUDED ARE BALLARD Read more

WW 0155 Status Updates
STATUS REPORT ON WW 155 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 S POF TO 35 S FAM TO 25 WNW SLO. ..SQUITIERI..04/21/25 ATTN...WFO...DVN...LSX...PAH...ILX... STATUS REPORT FOR WT 155 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC003-005-011-021-027-039-051-055-077-081-087-113-115-121-123- 135-139-145-147-153-155-173-181-189-195-199-203-210340- IL . ILLINOIS COUNTIES INCLUDED ARE ALEXANDER BOND BUREAU CHRISTIAN CLINTON DE WITT FAYETTE FRANKLIN JACKSON JEFFERSON JOHNSON MCLEAN MACON MARION MARSHALL MONTGOMERY MOULTRIE PERRY PIATT PULASKI PUTNAM SHELBY UNION WASHINGTON WHITESIDE WILLIAMSON WOODFORD KYC007-210340- KY . KENTUCKY COUNTIES INCLUDED ARE BALLARD Read more

WW 155 TORNADO IA IL KY MO 202040Z - 210400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 155 NWS Storm Prediction Center Norman OK 340 PM CDT Sun Apr 20 2025 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of southeastern Iowa western and centrl Illinois far western Kentucky eastern Missouri * Effective this Sunday afternoon and evening from 340 PM until 1100 PM CDT. * Primary threats include... A few tornadoes and a couple intense tornadoes possible Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Ongoing strong/severe thunderstorms are forecast to continue moving eastward/northeastward across Missouri this afternoon and evening, spreading into parts of southeastern Iowa and Illinois over the next several hours. Along with some hail risk, damaging wind gusts are expected, along with potential for tornadoes -- a couple of which could be strong. The tornado watch area is approximately along and 60 statute miles east and west of a line from 30 miles north northeast of Burlington IA to 15 miles east southeast of Poplar Bluff MO. 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. && OTHER WATCH INFORMATION...CONTINUE...WW 154... AVIATION...Tornadoes and 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 23040. ...Goss Read more

MD 0507 CONCERNING TORNADO WATCH 155... FOR EASTERN MISSOURI INTO ILLINOIS
Mesoscale Discussion 0507 NWS Storm Prediction Center Norman OK 0746 PM CDT Sun Apr 20 2025 Areas affected...eastern Missouri into Illinois Concerning...Tornado Watch 155... Valid 210046Z - 210215Z The severe weather threat for Tornado Watch 155 continues. SUMMARY...The severe threat continues across Tornado Watch 155. Strong to severe gusts appear to be the main threat along most of the line, though tornadoes remain possible, particularly with supercells. DISCUSSION...A mature squall line continues to progress eastward amid a strongly sheared, adequately unstable airmass. A line-embedded mesovortex across far west-central IL has supported several estimated/measured severe gusts. While buoyancy ahead of this portion of the line is beginning to diminish considerably, strong synoptic forcing and ambient flow aloft will continue to support mesovortex maintenance and associated strong/severe gust potential, at least in the near-term. Farther south in southeast MO, supercells have entered the southwestern-most portions of the watch, and it is here where short-term tornado potential is greatest. Given strong kinematic fields in place, despite waning buoyancy, at least damaging gust potential may persist with the line downstream, east of the current Tornado Watch, so either a new WW issuance may be needed, or a spatial extension of the ongoing watch may be warranted. ..Squitieri/Guyer.. 04/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...LOT...ILX...MEG...LSX...DVN... LAT...LON 36589107 37449084 39749049 40189062 40929107 41439127 41759097 41739019 41378915 40918861 39968815 38858800 37828812 37018841 36488904 36478985 36499042 36589107 MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 0157 Status Updates
STATUS FOR WATCH 0157 HAS NOT BEEN ISSUED YET Read more

WW 157 TORNADO IL 210155Z - 210900Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 157 NWS Storm Prediction Center Norman OK 855 PM CDT Sun Apr 20 2025 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northern Illinois * Effective this Sunday night and Monday morning from 855 PM until 400 AM CDT. * Primary threats include... A couple tornadoes possible Isolated damaging wind gusts to 70 mph possible SUMMARY...Associated with a line of storms, a brief tornado/wind damage risk may develop east-northeastward across additional parts of northern Illinois through mid/late evening. The tornado watch area is approximately along and 30 statute miles east and west of a line from 45 miles north northwest of Marseilles IL to 75 miles south southeast of Marseilles IL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). 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 155...WW 156... AVIATION...Tornadoes and 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 450. Mean storm motion vector 22035. ...Guyer Read more