Severe Storms

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0811 PM CDT Tue May 21 2024 Valid 220100Z - 221200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WISCONSIN AND ILLINOIS... ...SUMMARY... An outbreak of severe thunderstorms will continue this evening across parts of far eastern Iowa, eastern Missouri, northern Illinois and Wisconsin. A potential will exist for strong tornadoes and widespread damaging winds. The severe threat will also continue south-southwestward into the Ozarks and southern Plains, with a threat for isolated large hail, wind damage and a tornado or two. ...Mid To Upper Mississippi Valley/Western Great Lakes... The latest mosaic radar imagery shows scattered severe thunderstorms located from southern Wisconsin southward across far eastern Iowa, western Illinois into eastern and southern Missouri. The storms are located from a warm front in Wisconsin and extend southward into the mid Mississippi Valley along and near a pre-frontal trough. MLCAPE along this corridor is estimated by the RAP in the 2000 to 3000 J/kg range. On water vapor imagery, a shortwave trough, and an associated 70 to 90 knot mid-level jet is moving through southeast Iowa. This feature is enhancing large-scale ascent and deep-layer shear across much of the mid to upper Mississippi Valley. In addition, a 40 to 60 knot low-level jet is analyzed by the RAP over the mid to upper Mississippi Valley. As low-level flow continues to increase this evening, severe thunderstorm development will likely be maintained for several more hours. The 00Z sounding from Davenport, IA has MLCAPE near 2000 J/kg, with 0-6 km shear 50 to 55 knots and 0-3 km storm-relative helicity near 300 m2/s2. This appears to be representative of the environment further to the east, where much of the severe convection is ongoing. This will support supercells with tornadoes, wind damage and isolated large hail. The low-level shear will support a potential for strong tornadoes. The greatest threat for strong tornadoes will be near and to the east of the low-level jet from southern Wisconsin into northern Illinois. The greatest potential for wind damage will be along and ahead of organized line segments. Wind speeds of 70 to 80 mph will be possible with the more intense bowing line segments. Tornadoes may occur with rotating cells embedded in the line. Hailstones of greater than 2 inches in diameter will be possible with the more dominant supercell storms. The severe threat should become more isolated after midnight as instability decreases across the mid to upper Mississippi Valley. ...Ozarks/Southern Plains... Widely scattered strong to severe storms are ongoing across the Ozarks and in parts of the southern Plains, where the RAP is analyzing strong instability. To the east of a dryline, MLCAPE is estimated in the 3000 to 4000 J/kg range from eastern Oklahoma southward across much of the eastern half of Texas. Across the airmass to the east of the dryline, surface dewpoints are in the 70s F. In addition, the RAP has moderate to strong deep-layer shear analyzed across most of the moist airmass. The 00Z sounding at Little Rock, AR and Shreveport, LA have 0-6 km shear in the 50 to 60 knot range with 700-500 mb lapse rates in the 7.5 to 8 C/km range. This environment will be favorable for supercells with large hail. Hailstones greater than 2 inches in diameter will be possible with the more dominant supercells. Wind damage will also be likely with supercells, and or bowing line segments. The severe threat is expected to continue this evening, but should become more isolated toward midnight. ..Broyles.. 05/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0811 PM CDT Tue May 21 2024 Valid 220100Z - 221200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WISCONSIN AND ILLINOIS... ...SUMMARY... An outbreak of severe thunderstorms will continue this evening across parts of far eastern Iowa, eastern Missouri, northern Illinois and Wisconsin. A potential will exist for strong tornadoes and widespread damaging winds. The severe threat will also continue south-southwestward into the Ozarks and southern Plains, with a threat for isolated large hail, wind damage and a tornado or two. ...Mid To Upper Mississippi Valley/Western Great Lakes... The latest mosaic radar imagery shows scattered severe thunderstorms located from southern Wisconsin southward across far eastern Iowa, western Illinois into eastern and southern Missouri. The storms are located from a warm front in Wisconsin and extend southward into the mid Mississippi Valley along and near a pre-frontal trough. MLCAPE along this corridor is estimated by the RAP in the 2000 to 3000 J/kg range. On water vapor imagery, a shortwave trough, and an associated 70 to 90 knot mid-level jet is moving through southeast Iowa. This feature is enhancing large-scale ascent and deep-layer shear across much of the mid to upper Mississippi Valley. In addition, a 40 to 60 knot low-level jet is analyzed by the RAP over the mid to upper Mississippi Valley. As low-level flow continues to increase this evening, severe thunderstorm development will likely be maintained for several more hours. The 00Z sounding from Davenport, IA has MLCAPE near 2000 J/kg, with 0-6 km shear 50 to 55 knots and 0-3 km storm-relative helicity near 300 m2/s2. This appears to be representative of the environment further to the east, where much of the severe convection is ongoing. This will support supercells with tornadoes, wind damage and isolated large hail. The low-level shear will support a potential for strong tornadoes. The greatest threat for strong tornadoes will be near and to the east of the low-level jet from southern Wisconsin into northern Illinois. The greatest potential for wind damage will be along and ahead of organized line segments. Wind speeds of 70 to 80 mph will be possible with the more intense bowing line segments. Tornadoes may occur with rotating cells embedded in the line. Hailstones of greater than 2 inches in diameter will be possible with the more dominant supercell storms. The severe threat should become more isolated after midnight as instability decreases across the mid to upper Mississippi Valley. ...Ozarks/Southern Plains... Widely scattered strong to severe storms are ongoing across the Ozarks and in parts of the southern Plains, where the RAP is analyzing strong instability. To the east of a dryline, MLCAPE is estimated in the 3000 to 4000 J/kg range from eastern Oklahoma southward across much of the eastern half of Texas. Across the airmass to the east of the dryline, surface dewpoints are in the 70s F. In addition, the RAP has moderate to strong deep-layer shear analyzed across most of the moist airmass. The 00Z sounding at Little Rock, AR and Shreveport, LA have 0-6 km shear in the 50 to 60 knot range with 700-500 mb lapse rates in the 7.5 to 8 C/km range. This environment will be favorable for supercells with large hail. Hailstones greater than 2 inches in diameter will be possible with the more dominant supercells. Wind damage will also be likely with supercells, and or bowing line segments. The severe threat is expected to continue this evening, but should become more isolated toward midnight. ..Broyles.. 05/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0811 PM CDT Tue May 21 2024 Valid 220100Z - 221200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WISCONSIN AND ILLINOIS... ...SUMMARY... An outbreak of severe thunderstorms will continue this evening across parts of far eastern Iowa, eastern Missouri, northern Illinois and Wisconsin. A potential will exist for strong tornadoes and widespread damaging winds. The severe threat will also continue south-southwestward into the Ozarks and southern Plains, with a threat for isolated large hail, wind damage and a tornado or two. ...Mid To Upper Mississippi Valley/Western Great Lakes... The latest mosaic radar imagery shows scattered severe thunderstorms located from southern Wisconsin southward across far eastern Iowa, western Illinois into eastern and southern Missouri. The storms are located from a warm front in Wisconsin and extend southward into the mid Mississippi Valley along and near a pre-frontal trough. MLCAPE along this corridor is estimated by the RAP in the 2000 to 3000 J/kg range. On water vapor imagery, a shortwave trough, and an associated 70 to 90 knot mid-level jet is moving through southeast Iowa. This feature is enhancing large-scale ascent and deep-layer shear across much of the mid to upper Mississippi Valley. In addition, a 40 to 60 knot low-level jet is analyzed by the RAP over the mid to upper Mississippi Valley. As low-level flow continues to increase this evening, severe thunderstorm development will likely be maintained for several more hours. The 00Z sounding from Davenport, IA has MLCAPE near 2000 J/kg, with 0-6 km shear 50 to 55 knots and 0-3 km storm-relative helicity near 300 m2/s2. This appears to be representative of the environment further to the east, where much of the severe convection is ongoing. This will support supercells with tornadoes, wind damage and isolated large hail. The low-level shear will support a potential for strong tornadoes. The greatest threat for strong tornadoes will be near and to the east of the low-level jet from southern Wisconsin into northern Illinois. The greatest potential for wind damage will be along and ahead of organized line segments. Wind speeds of 70 to 80 mph will be possible with the more intense bowing line segments. Tornadoes may occur with rotating cells embedded in the line. Hailstones of greater than 2 inches in diameter will be possible with the more dominant supercell storms. The severe threat should become more isolated after midnight as instability decreases across the mid to upper Mississippi Valley. ...Ozarks/Southern Plains... Widely scattered strong to severe storms are ongoing across the Ozarks and in parts of the southern Plains, where the RAP is analyzing strong instability. To the east of a dryline, MLCAPE is estimated in the 3000 to 4000 J/kg range from eastern Oklahoma southward across much of the eastern half of Texas. Across the airmass to the east of the dryline, surface dewpoints are in the 70s F. In addition, the RAP has moderate to strong deep-layer shear analyzed across most of the moist airmass. The 00Z sounding at Little Rock, AR and Shreveport, LA have 0-6 km shear in the 50 to 60 knot range with 700-500 mb lapse rates in the 7.5 to 8 C/km range. This environment will be favorable for supercells with large hail. Hailstones greater than 2 inches in diameter will be possible with the more dominant supercells. Wind damage will also be likely with supercells, and or bowing line segments. The severe threat is expected to continue this evening, but should become more isolated toward midnight. ..Broyles.. 05/22/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0811 PM CDT Tue May 21 2024 Valid 220100Z - 221200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF WISCONSIN AND ILLINOIS... ...SUMMARY... An outbreak of severe thunderstorms will continue this evening across parts of far eastern Iowa, eastern Missouri, northern Illinois and Wisconsin. A potential will exist for strong tornadoes and widespread damaging winds. The severe threat will also continue south-southwestward into the Ozarks and southern Plains, with a threat for isolated large hail, wind damage and a tornado or two. ...Mid To Upper Mississippi Valley/Western Great Lakes... The latest mosaic radar imagery shows scattered severe thunderstorms located from southern Wisconsin southward across far eastern Iowa, western Illinois into eastern and southern Missouri. The storms are located from a warm front in Wisconsin and extend southward into the mid Mississippi Valley along and near a pre-frontal trough. MLCAPE along this corridor is estimated by the RAP in the 2000 to 3000 J/kg range. On water vapor imagery, a shortwave trough, and an associated 70 to 90 knot mid-level jet is moving through southeast Iowa. This feature is enhancing large-scale ascent and deep-layer shear across much of the mid to upper Mississippi Valley. In addition, a 40 to 60 knot low-level jet is analyzed by the RAP over the mid to upper Mississippi Valley. As low-level flow continues to increase this evening, severe thunderstorm development will likely be maintained for several more hours. The 00Z sounding from Davenport, IA has MLCAPE near 2000 J/kg, with 0-6 km shear 50 to 55 knots and 0-3 km storm-relative helicity near 300 m2/s2. This appears to be representative of the environment further to the east, where much of the severe convection is ongoing. This will support supercells with tornadoes, wind damage and isolated large hail. The low-level shear will support a potential for strong tornadoes. The greatest threat for strong tornadoes will be near and to the east of the low-level jet from southern Wisconsin into northern Illinois. The greatest potential for wind damage will be along and ahead of organized line segments. Wind speeds of 70 to 80 mph will be possible with the more intense bowing line segments. Tornadoes may occur with rotating cells embedded in the line. Hailstones of greater than 2 inches in diameter will be possible with the more dominant supercell storms. The severe threat should become more isolated after midnight as instability decreases across the mid to upper Mississippi Valley. ...Ozarks/Southern Plains... Widely scattered strong to severe storms are ongoing across the Ozarks and in parts of the southern Plains, where the RAP is analyzing strong instability. To the east of a dryline, MLCAPE is estimated in the 3000 to 4000 J/kg range from eastern Oklahoma southward across much of the eastern half of Texas. Across the airmass to the east of the dryline, surface dewpoints are in the 70s F. In addition, the RAP has moderate to strong deep-layer shear analyzed across most of the moist airmass. The 00Z sounding at Little Rock, AR and Shreveport, LA have 0-6 km shear in the 50 to 60 knot range with 700-500 mb lapse rates in the 7.5 to 8 C/km range. This environment will be favorable for supercells with large hail. Hailstones greater than 2 inches in diameter will be possible with the more dominant supercells. Wind damage will also be likely with supercells, and or bowing line segments. The severe threat is expected to continue this evening, but should become more isolated toward midnight. ..Broyles.. 05/22/2024 Read more

WW 0282 Status Updates
STATUS REPORT ON WW 282 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/22/24 ATTN...WFO...LOT...DVN... STATUS REPORT FOR WT 282 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-011-037-089-093-099-103-111-141-155-177-201-220140- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE BUREAU DE KALB KANE KENDALL LA SALLE LEE MCHENRY OGLE PUTNAM STEPHENSON WINNEBAGO 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 0282 Status Updates
STATUS REPORT ON WW 282 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/22/24 ATTN...WFO...LOT...DVN... STATUS REPORT FOR WT 282 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC007-011-037-089-093-099-103-111-141-155-177-201-220140- IL . ILLINOIS COUNTIES INCLUDED ARE BOONE BUREAU DE KALB KANE KENDALL LA SALLE LEE MCHENRY OGLE PUTNAM STEPHENSON WINNEBAGO 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 0881 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR CENTRAL WISCONSIN
Mesoscale Discussion 0881 NWS Storm Prediction Center Norman OK 0618 PM CDT Tue May 21 2024 Areas affected...Central Wisconsin Concerning...Severe potential...Tornado Watch likely Valid 212318Z - 220045Z Probability of Watch Issuance...80 percent SUMMARY...A tornado and damaging wind threat will increase across portions of central WI as a line of thunderstorms, with embedded supercells, continues to rapidly move northeastward out of IA through this evening. DISCUSSION...A line of severe thunderstorms extending from far southeastern MN through east central IA, and additional new thunderstorm development ahead of it, will continue to move into a favorable low-level shear tornadic environment across central WI characterized by 50 kt of 0-1 km shear. Although recent visible satellite imagery and mesoanalysis indicates this downstream region is more convectively inhibited, strong forcing via a mid level shortwave trough and cold front will likely overcome it. An initial threat of discrete supercells will be possible early this evening, with upscale growth into a line expected late tonight. Even so, any bowing line segments lifting north-northeastward within it will become more favorably oriented with the low-level shear vector (orthogonal), presenting an opportunity for embedded mesovortices and damaging winds. ..Barnes/Thompson.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...MKX...DLH...ARX...MPX... LAT...LON 44569208 44889238 45129244 45539199 45679140 45679078 45519020 45298967 44988893 44748815 44718809 44318796 43808803 43558806 43578855 43648970 43669023 43769067 43979095 44569122 44569208 Read more

WW 0281 Status Updates
STATUS REPORT ON WW 281 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SW VOK TO 35 E EAU TO 35 NE EAU. ..HART..05/22/24 ATTN...WFO...ARX...GRB...MPX... STATUS REPORT FOR WT 281 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS WIC001-009-015-019-029-053-057-061-067-069-071-073-075-078-081- 083-087-097-115-119-135-137-139-141-220140- WI . WISCONSIN COUNTIES INCLUDED ARE ADAMS BROWN CALUMET CLARK DOOR JACKSON JUNEAU KEWAUNEE LANGLADE LINCOLN MANITOWOC MARATHON MARINETTE MENOMINEE MONROE OCONTO OUTAGAMIE PORTAGE SHAWANO TAYLOR WAUPACA WAUSHARA WINNEBAGO WOOD LMZ521-522-541-542-543-220140- CW . ADJACENT COASTAL WATERS INCLUDED ARE GREEN BAY SOUTH OF LINE FROM CEDAR RIVER TO ROCK ISLAND PASSAGE AND NORTH OF A LINE FROM OCONTO WI TO LITTLE STURGEON BAY WI Read more

WW 0280 Status Updates
STATUS REPORT ON WW 280 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/22/24 ATTN...WFO...LSX...ILX...DVN...SGF... STATUS REPORT FOR WT 280 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-013-017-057-061-067-083-095-109-125-137-149-169-171- 220140- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN CALHOUN CASS FULTON GREENE HANCOCK JERSEY KNOX MCDONOUGH MASON MORGAN PIKE SCHUYLER SCOTT MOC007-019-027-045-051-055-065-067-071-073-091-093-099-103-111- 113-125-127-131-135-137-139-149-151-153-161-163-169-173-179-183- 189-199-203-205-213-215-219-221-229-510-220140- MO . MISSOURI COUNTIES INCLUDED ARE AUDRAIN BOONE CALLAWAY CLARK COLE CRAWFORD DENT DOUGLAS FRANKLIN GASCONADE HOWELL IRON JEFFERSON KNOX LEWIS LINCOLN MARIES MARION Read more

WW 0279 Status Updates
STATUS REPORT ON WW 279 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/22/24 ATTN...WFO...MKX... STATUS REPORT FOR WT 279 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS WIC021-025-027-039-045-047-049-055-059-065-077-079-089-101-105- 111-117-127-131-133-220140- WI . WISCONSIN COUNTIES INCLUDED ARE COLUMBIA DANE DODGE FOND DU LAC GREEN GREEN LAKE IOWA JEFFERSON KENOSHA LAFAYETTE MARQUETTE MILWAUKEE OZAUKEE RACINE ROCK SAUK SHEBOYGAN WALWORTH WASHINGTON WAUKESHA LMZ643-644-645-646-220140- CW . ADJACENT COASTAL WATERS INCLUDED ARE LMZ643 LMZ644 LMZ645 Read more

WW 0279 Status Updates
STATUS REPORT ON WW 279 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/22/24 ATTN...WFO...MKX... STATUS REPORT FOR WT 279 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS WIC021-025-027-039-045-047-049-055-059-065-077-079-089-101-105- 111-117-127-131-133-220140- WI . WISCONSIN COUNTIES INCLUDED ARE COLUMBIA DANE DODGE FOND DU LAC GREEN GREEN LAKE IOWA JEFFERSON KENOSHA LAFAYETTE MARQUETTE MILWAUKEE OZAUKEE RACINE ROCK SAUK SHEBOYGAN WALWORTH WASHINGTON WAUKESHA LMZ643-644-645-646-220140- CW . ADJACENT COASTAL WATERS INCLUDED ARE LMZ643 LMZ644 LMZ645 Read more

WW 0278 Status Updates
STATUS REPORT ON WW 278 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NW MKO TO 45 NW SGF TO 35 E SZL TO 35 S OTM. ..HART..05/22/24 ATTN...WFO...TSA...ICT...TOP...EAX...SGF... STATUS REPORT FOR WT 278 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-015-087-143-220140- AR . ARKANSAS COUNTIES INCLUDED ARE BENTON CARROLL MADISON WASHINGTON MOC001-009-015-029-039-043-053-057-059-077-085-089-097-105-109- 119-121-141-145-167-175-185-197-209-225-220140- MO . MISSOURI COUNTIES INCLUDED ARE ADAIR BARRY BENTON CAMDEN CEDAR CHRISTIAN COOPER DADE DALLAS GREENE HICKORY HOWARD JASPER LACLEDE LAWRENCE MCDONALD MACON MORGAN NEWTON POLK RANDOLPH ST. CLAIR SCHUYLER STONE WEBSTER Read more

WW 0277 Status Updates
STATUS REPORT ON WW 277 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NNW IRK TO 40 S LSE TO 35 ESE EAU TO 30 E EAU. ..HART..05/22/24 ATTN...WFO...DMX...ARX...DVN...MPX... STATUS REPORT FOR WT 277 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC015-071-073-085-131-161-187-195-220140- IL . ILLINOIS COUNTIES INCLUDED ARE CARROLL HENDERSON HENRY JO DAVIESS MERCER ROCK ISLAND WARREN WHITESIDE IAC011-019-031-043-045-051-055-057-061-087-095-097-101-103-105- 107-111-113-115-139-163-177-179-183-220140- IA . IOWA COUNTIES INCLUDED ARE BENTON BUCHANAN CEDAR CLAYTON CLINTON DAVIS DELAWARE DES MOINES DUBUQUE HENRY IOWA JACKSON JEFFERSON JOHNSON JONES KEOKUK LEE LINN LOUISA MUSCATINE SCOTT VAN BUREN WAPELLO WASHINGTON Read more

MD 0880 CONCERNING TORNADO WATCH 278... FOR PARTS OF WEST CENTRAL ILLINOIS AND NORTHEASTERN MISSOURI SOUTHWESTWARD INTO NORTHEASTERN OKLAHOMA
Mesoscale Discussion 0880 NWS Storm Prediction Center Norman OK 0533 PM CDT Tue May 21 2024 Areas affected...parts of west central Illinois and northeastern Missouri southwestward into northeastern Oklahoma Concerning...Tornado Watch 278... Valid 212233Z - 220030Z The severe weather threat for Tornado Watch 278 continues. SUMMARY...Supercell development will persist in narrow east-southeastward pre-frontal corridor, with some potential the continued evolution of an organizing squall line through 7-9 PM CDT. Stronger storms will continue to pose a risk for large hail, locally damaging wind gusts and a couple of tornadoes. DISCUSSION...Thunderstorm development persists just east of the dryline as a southeastward advancing cold front overtakes it. Activity has evolved into a mix of linear and discrete supercell cell structures, which will tend to slowly shift southeastward as the deep cyclone continues migrating northeastward through the Upper Midwest, and flow to its south veers to a more prominent westerly component and begins to weaken. Convection is still embedded within strong southwesterly deep-layer mean flow in excess of 50 kt, which is supporting fast northeasterly cell motion, but at least somewhat drier and less unstable boundary-layer air lingers across south central through east central Missouri and west central Illinois. Stronger convective development probably will remain focused in the rather narrow corridor of better pre-frontal low-level, which guidance does suggest will tend to shift eastward ahead of the front toward the middle Mississippi Valley through 01-03Z. Within this narrow corridor, large CAPE and strong shear will maintain a risk for severe hail/wind and potential for a couple of tornadoes several more hours ..Kerr.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX...DVN...SGF...EAX...TSA... LAT...LON 40539230 39949043 36969267 36199384 35839584 37409421 39489283 40539230 Read more

MD 0881 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR CENTRAL WISCONSIN
Mesoscale Discussion 0881 NWS Storm Prediction Center Norman OK 0618 PM CDT Tue May 21 2024 Areas affected...Central Wisconsin Concerning...Severe potential...Tornado Watch likely Valid 212318Z - 220045Z Probability of Watch Issuance...80 percent SUMMARY...A tornado and damaging wind threat will increase across portions of central WI as a line of thunderstorms, with embedded supercells, continues to rapidly move northeastward out of IA through this evening. DISCUSSION...A line of severe thunderstorms extending from far southeastern MN through east central IA, and additional new thunderstorm development ahead of it, will continue to move into a favorable low-level shear tornadic environment across central WI characterized by 50 kt of 0-1 km shear. Although recent visible satellite imagery and mesoanalysis indicates this downstream region is more convectively inhibited, strong forcing via a mid level shortwave trough and cold front will likely overcome it. An initial threat of discrete supercells will be possible early this evening, with upscale growth into a line expected late tonight. Even so, any bowing line segments lifting north-northeastward within it will become more favorably oriented with the low-level shear vector (orthogonal), presenting an opportunity for embedded mesovortices and damaging winds. ..Barnes/Thompson.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...MKX...DLH...ARX...MPX... LAT...LON 44569208 44889238 45129244 45539199 45679140 45679078 45519020 45298967 44988893 44748815 44718809 44318796 43808803 43558806 43578855 43648970 43669023 43769067 43979095 44569122 44569208 Read more

MD 0880 CONCERNING TORNADO WATCH 278... FOR PARTS OF WEST CENTRAL ILLINOIS AND NORTHEASTERN MISSOURI SOUTHWESTWARD INTO NORTHEASTERN OKLAHOMA
Mesoscale Discussion 0880 NWS Storm Prediction Center Norman OK 0533 PM CDT Tue May 21 2024 Areas affected...parts of west central Illinois and northeastern Missouri southwestward into northeastern Oklahoma Concerning...Tornado Watch 278... Valid 212233Z - 220030Z The severe weather threat for Tornado Watch 278 continues. SUMMARY...Supercell development will persist in narrow east-southeastward pre-frontal corridor, with some potential the continued evolution of an organizing squall line through 7-9 PM CDT. Stronger storms will continue to pose a risk for large hail, locally damaging wind gusts and a couple of tornadoes. DISCUSSION...Thunderstorm development persists just east of the dryline as a southeastward advancing cold front overtakes it. Activity has evolved into a mix of linear and discrete supercell cell structures, which will tend to slowly shift southeastward as the deep cyclone continues migrating northeastward through the Upper Midwest, and flow to its south veers to a more prominent westerly component and begins to weaken. Convection is still embedded within strong southwesterly deep-layer mean flow in excess of 50 kt, which is supporting fast northeasterly cell motion, but at least somewhat drier and less unstable boundary-layer air lingers across south central through east central Missouri and west central Illinois. Stronger convective development probably will remain focused in the rather narrow corridor of better pre-frontal low-level, which guidance does suggest will tend to shift eastward ahead of the front toward the middle Mississippi Valley through 01-03Z. Within this narrow corridor, large CAPE and strong shear will maintain a risk for severe hail/wind and potential for a couple of tornadoes several more hours ..Kerr.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILX...LSX...DVN...SGF...EAX...TSA... LAT...LON 40539230 39949043 36969267 36199384 35839584 37409421 39489283 40539230 Read more

MD 0879 CONCERNING TORNADO WATCH 277... FOR CENTRAL IOWA INTO NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN.
Mesoscale Discussion 0879 NWS Storm Prediction Center Norman OK 0509 PM CDT Tue May 21 2024 Areas affected...Central Iowa into northeast Iowa and far southwest Wisconsin. Concerning...Tornado Watch 277... Valid 212209Z - 212345Z The severe weather threat for Tornado Watch 277 continues. SUMMARY...Intense to potentially violent tornado threat across northeast Iowa and into southwest Wisconsin over the next 2 hours DISCUSSION...The supercell which formed the intense to potentially violent tornado which impacted Greenfield and other portions of southwest Iowa this afternoon has re-intensified after storm mergers. This storm and another strong supercell to its south are moving into an increasingly favorable tornadic environment with a STP of 5 to 6 (per SPC mesoanalysis). The backed surface winds and vorticity rich environment in the wake of the morning convection will provide ample low-level vorticity for a sustained tornado threat into the early evening. One or more long-track, potentially violent tornadoes are possible in this corridor over the next 90 to 120 minutes. ..Bentley/Thompson.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...DMX... LAT...LON 43319094 43149080 42899079 42509117 41569273 41459346 42039360 42679316 43289233 43499174 43489133 43499120 43319094 Read more

WW 0281 Status Updates
STATUS FOR WATCH 0281 HAS NOT BEEN ISSUED YET Read more

WW 281 TORNADO WI LM 212340Z - 220500Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 281 NWS Storm Prediction Center Norman OK 640 PM CDT Tue May 21 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and northeast Wisconsin Lake Michigan * Effective this Tuesday night from 640 PM until Midnight CDT. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Widespread damaging winds and isolated significant gusts to 80 mph likely Scattered large hail events to 1 inch in diameter possible SUMMARY...Initial supercells will consolidate into a more solid squall line that will move rapidly northeastward across Wisconsin through early tonight. Embedded circulations will be capable of producing tornadoes (a couple of which could produce roughly EF2 damage), damaging gusts up to 80 mph, and isolated large hail near 1 inch in diameter for the next several hours. The tornado watch area is approximately along and 85 statute miles east and west of a line from 35 miles northeast of Wausau WI to 35 miles southwest of Oshkosh WI. 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 277...WW 278...WW 279...WW 280... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24050. ...Thompson Read more

WW 0280 Status Updates
STATUS REPORT ON WW 280 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..HART..05/21/24 ATTN...WFO...LSX...ILX...DVN...SGF... STATUS REPORT FOR WT 280 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-013-017-057-061-067-083-095-109-125-137-149-169-171- 220040- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN CALHOUN CASS FULTON GREENE HANCOCK JERSEY KNOX MCDONOUGH MASON MORGAN PIKE SCHUYLER SCOTT MOC007-019-027-045-051-055-065-067-071-073-091-093-099-103-111- 113-125-127-131-135-137-139-149-151-153-161-163-169-173-179-183- 189-199-203-205-213-215-219-221-229-510-220040- MO . MISSOURI COUNTIES INCLUDED ARE AUDRAIN BOONE CALLAWAY CLARK COLE CRAWFORD DENT DOUGLAS FRANKLIN GASCONADE HOWELL IRON JEFFERSON KNOX LEWIS LINCOLN MARIES MARION Read more