Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Thu Aug 29 2024 Valid 301200Z - 311200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE LAKE HURON AND ERIE VICINITY WEST-SOUTHWESTWARD ACROSS THE MIDWEST... ...SUMMARY... Strong/locally severe storms will be possible from Lakes Huron and Erie southwestward into the Midwest Friday. ...Synopsis... An upper-level trough will continue moving slowly eastward out of the north-central U.S. across the Great Lakes and Midwest on Friday, with the more vigorous portion of the trough expected to eject northeastward across western Ontario into the Hudson Bay region. At the surface, a cold front is forecast to continue eastward across the Great Lakes, southeastward across the Midwest, and slowly southward across the southern Plains. By the end of the period, the front should extend from the Lower Great Lakes west-southwestward across the Ohio Valley, and into Oklahoma and northern Texas. ...Lower Michigan/northern Ohio/northwestern Pennsylvania across the Midwest... Moderate destabilization is expected in tandem with afternoon heating ahead of the cold front, from Lower Michigan west-southwestward across northern Illinois and Missouri, and southward across the warm sector. As the front slowly advances, scattered thunderstorm development is expected, initially across the lower Michigan and potentially into parts of Ohio, and then expanding southwestward across Indiana, Illinois, and into Missouri. Although the stronger deep-layer shear will largely remain to the cool side of the front, modest westerly mid-level flow of 20-25 kts will favor loosely organized storms, with some potential for upscale growth/clustering. Strong/isolated damaging gusts and perhaps severe hail will be possible. While risk should diminish after dark, convection -- and very limited risk with a couple of stronger storms -- may continue well into the overnight hours. ..Goss.. 08/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Thu Aug 29 2024 Valid 301200Z - 311200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE LAKE HURON AND ERIE VICINITY WEST-SOUTHWESTWARD ACROSS THE MIDWEST... ...SUMMARY... Strong/locally severe storms will be possible from Lakes Huron and Erie southwestward into the Midwest Friday. ...Synopsis... An upper-level trough will continue moving slowly eastward out of the north-central U.S. across the Great Lakes and Midwest on Friday, with the more vigorous portion of the trough expected to eject northeastward across western Ontario into the Hudson Bay region. At the surface, a cold front is forecast to continue eastward across the Great Lakes, southeastward across the Midwest, and slowly southward across the southern Plains. By the end of the period, the front should extend from the Lower Great Lakes west-southwestward across the Ohio Valley, and into Oklahoma and northern Texas. ...Lower Michigan/northern Ohio/northwestern Pennsylvania across the Midwest... Moderate destabilization is expected in tandem with afternoon heating ahead of the cold front, from Lower Michigan west-southwestward across northern Illinois and Missouri, and southward across the warm sector. As the front slowly advances, scattered thunderstorm development is expected, initially across the lower Michigan and potentially into parts of Ohio, and then expanding southwestward across Indiana, Illinois, and into Missouri. Although the stronger deep-layer shear will largely remain to the cool side of the front, modest westerly mid-level flow of 20-25 kts will favor loosely organized storms, with some potential for upscale growth/clustering. Strong/isolated damaging gusts and perhaps severe hail will be possible. While risk should diminish after dark, convection -- and very limited risk with a couple of stronger storms -- may continue well into the overnight hours. ..Goss.. 08/29/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Thu Aug 29 2024 Valid 301200Z - 311200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE LAKE HURON AND ERIE VICINITY WEST-SOUTHWESTWARD ACROSS THE MIDWEST... ...SUMMARY... Strong/locally severe storms will be possible from Lakes Huron and Erie southwestward into the Midwest Friday. ...Synopsis... An upper-level trough will continue moving slowly eastward out of the north-central U.S. across the Great Lakes and Midwest on Friday, with the more vigorous portion of the trough expected to eject northeastward across western Ontario into the Hudson Bay region. At the surface, a cold front is forecast to continue eastward across the Great Lakes, southeastward across the Midwest, and slowly southward across the southern Plains. By the end of the period, the front should extend from the Lower Great Lakes west-southwestward across the Ohio Valley, and into Oklahoma and northern Texas. ...Lower Michigan/northern Ohio/northwestern Pennsylvania across the Midwest... Moderate destabilization is expected in tandem with afternoon heating ahead of the cold front, from Lower Michigan west-southwestward across northern Illinois and Missouri, and southward across the warm sector. As the front slowly advances, scattered thunderstorm development is expected, initially across the lower Michigan and potentially into parts of Ohio, and then expanding southwestward across Indiana, Illinois, and into Missouri. Although the stronger deep-layer shear will largely remain to the cool side of the front, modest westerly mid-level flow of 20-25 kts will favor loosely organized storms, with some potential for upscale growth/clustering. Strong/isolated damaging gusts and perhaps severe hail will be possible. While risk should diminish after dark, convection -- and very limited risk with a couple of stronger storms -- may continue well into the overnight hours. ..Goss.. 08/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Thu Aug 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER/MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms are expected across the Upper/Middle Mississippi Valley to the central Plains. A few severe storms also will be possible over portions of the mid-Atlantic region. ...Upper/Middle Mississippi Valley... Southern portions of a strong upper trough, currently located over the northern Rockies, will eject across the Dakotas this afternoon. As 70-80kt 500mb speed max translates through the base of the trough across ND, primary upper low will track across southern AB into northwestern ON during the latter half of the period. Latest model guidance suggests very strong 12hr mid-level height falls just north of the international border, with more modest falls into the upper Mississippi Valley by 29/00z. Strong low-level warm advection will likely prove instrumental in one or more thunderstorm clusters over eastern ND/northwestern MN at the start of the period. LLJ responsible for this activity will shift into northwestern ON during the day, and this warm-advection activity should lift north of the border as well. However, strong boundary-layer heating will occur across eastern NE into extreme southwest MN by early afternoon. This will aid instability, and CINH will begin to weaken along the front, as surface temperatures rise into the mid 80s across central MN. NAM forecast sounding for KLJF at 22z is thermodynamically impressive with MLCAPE around 5400 J/kg and 0-6km shear approaching 30kt. 30-35kt deep-layer shear is expected along the northern extent of the stronger buoyancy. As a result, supercells are expected to develop along/ahead of the cold front, supported aloft by the upstream short wave. Large hail, severe gusts, and a few tornadoes are the expected hazards with these storms. Scattered convection, with a more-isolated severe threat, is forecast along the trailing cold front across the central Plains as readings breach convective temperatures later in the afternoon. Wind profiles at lower latitudes are not very strong, so this activity will be multicellular and less organized. Even so, some risk for hail/wind can be expected into the evening hours. ...Middle Atlantic Region... Dominant surface anticyclone over southeastern Canada will shift across ON/QC, which will allow a synoptic front to drape itself across the Middle Atlantic during the afternoon. This boundary will focus scattered thunderstorms as convective temperatures are breached by mid afternoon. Wind profiles favor mostly disorganized pulse-multicell updrafts. These storms will move slowly southeast with an attendant risk for wind and perhaps some hail. Robust updrafts will be strongly diurnally driven. ..Darrow/Jirak.. 08/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Thu Aug 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER/MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms are expected across the Upper/Middle Mississippi Valley to the central Plains. A few severe storms also will be possible over portions of the mid-Atlantic region. ...Upper/Middle Mississippi Valley... Southern portions of a strong upper trough, currently located over the northern Rockies, will eject across the Dakotas this afternoon. As 70-80kt 500mb speed max translates through the base of the trough across ND, primary upper low will track across southern AB into northwestern ON during the latter half of the period. Latest model guidance suggests very strong 12hr mid-level height falls just north of the international border, with more modest falls into the upper Mississippi Valley by 29/00z. Strong low-level warm advection will likely prove instrumental in one or more thunderstorm clusters over eastern ND/northwestern MN at the start of the period. LLJ responsible for this activity will shift into northwestern ON during the day, and this warm-advection activity should lift north of the border as well. However, strong boundary-layer heating will occur across eastern NE into extreme southwest MN by early afternoon. This will aid instability, and CINH will begin to weaken along the front, as surface temperatures rise into the mid 80s across central MN. NAM forecast sounding for KLJF at 22z is thermodynamically impressive with MLCAPE around 5400 J/kg and 0-6km shear approaching 30kt. 30-35kt deep-layer shear is expected along the northern extent of the stronger buoyancy. As a result, supercells are expected to develop along/ahead of the cold front, supported aloft by the upstream short wave. Large hail, severe gusts, and a few tornadoes are the expected hazards with these storms. Scattered convection, with a more-isolated severe threat, is forecast along the trailing cold front across the central Plains as readings breach convective temperatures later in the afternoon. Wind profiles at lower latitudes are not very strong, so this activity will be multicellular and less organized. Even so, some risk for hail/wind can be expected into the evening hours. ...Middle Atlantic Region... Dominant surface anticyclone over southeastern Canada will shift across ON/QC, which will allow a synoptic front to drape itself across the Middle Atlantic during the afternoon. This boundary will focus scattered thunderstorms as convective temperatures are breached by mid afternoon. Wind profiles favor mostly disorganized pulse-multicell updrafts. These storms will move slowly southeast with an attendant risk for wind and perhaps some hail. Robust updrafts will be strongly diurnally driven. ..Darrow/Jirak.. 08/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Thu Aug 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER/MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms are expected across the Upper/Middle Mississippi Valley to the central Plains. A few severe storms also will be possible over portions of the mid-Atlantic region. ...Upper/Middle Mississippi Valley... Southern portions of a strong upper trough, currently located over the northern Rockies, will eject across the Dakotas this afternoon. As 70-80kt 500mb speed max translates through the base of the trough across ND, primary upper low will track across southern AB into northwestern ON during the latter half of the period. Latest model guidance suggests very strong 12hr mid-level height falls just north of the international border, with more modest falls into the upper Mississippi Valley by 29/00z. Strong low-level warm advection will likely prove instrumental in one or more thunderstorm clusters over eastern ND/northwestern MN at the start of the period. LLJ responsible for this activity will shift into northwestern ON during the day, and this warm-advection activity should lift north of the border as well. However, strong boundary-layer heating will occur across eastern NE into extreme southwest MN by early afternoon. This will aid instability, and CINH will begin to weaken along the front, as surface temperatures rise into the mid 80s across central MN. NAM forecast sounding for KLJF at 22z is thermodynamically impressive with MLCAPE around 5400 J/kg and 0-6km shear approaching 30kt. 30-35kt deep-layer shear is expected along the northern extent of the stronger buoyancy. As a result, supercells are expected to develop along/ahead of the cold front, supported aloft by the upstream short wave. Large hail, severe gusts, and a few tornadoes are the expected hazards with these storms. Scattered convection, with a more-isolated severe threat, is forecast along the trailing cold front across the central Plains as readings breach convective temperatures later in the afternoon. Wind profiles at lower latitudes are not very strong, so this activity will be multicellular and less organized. Even so, some risk for hail/wind can be expected into the evening hours. ...Middle Atlantic Region... Dominant surface anticyclone over southeastern Canada will shift across ON/QC, which will allow a synoptic front to drape itself across the Middle Atlantic during the afternoon. This boundary will focus scattered thunderstorms as convective temperatures are breached by mid afternoon. Wind profiles favor mostly disorganized pulse-multicell updrafts. These storms will move slowly southeast with an attendant risk for wind and perhaps some hail. Robust updrafts will be strongly diurnally driven. ..Darrow/Jirak.. 08/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Thu Aug 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER/MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms are expected across the Upper/Middle Mississippi Valley to the central Plains. A few severe storms also will be possible over portions of the mid-Atlantic region. ...Upper/Middle Mississippi Valley... Southern portions of a strong upper trough, currently located over the northern Rockies, will eject across the Dakotas this afternoon. As 70-80kt 500mb speed max translates through the base of the trough across ND, primary upper low will track across southern AB into northwestern ON during the latter half of the period. Latest model guidance suggests very strong 12hr mid-level height falls just north of the international border, with more modest falls into the upper Mississippi Valley by 29/00z. Strong low-level warm advection will likely prove instrumental in one or more thunderstorm clusters over eastern ND/northwestern MN at the start of the period. LLJ responsible for this activity will shift into northwestern ON during the day, and this warm-advection activity should lift north of the border as well. However, strong boundary-layer heating will occur across eastern NE into extreme southwest MN by early afternoon. This will aid instability, and CINH will begin to weaken along the front, as surface temperatures rise into the mid 80s across central MN. NAM forecast sounding for KLJF at 22z is thermodynamically impressive with MLCAPE around 5400 J/kg and 0-6km shear approaching 30kt. 30-35kt deep-layer shear is expected along the northern extent of the stronger buoyancy. As a result, supercells are expected to develop along/ahead of the cold front, supported aloft by the upstream short wave. Large hail, severe gusts, and a few tornadoes are the expected hazards with these storms. Scattered convection, with a more-isolated severe threat, is forecast along the trailing cold front across the central Plains as readings breach convective temperatures later in the afternoon. Wind profiles at lower latitudes are not very strong, so this activity will be multicellular and less organized. Even so, some risk for hail/wind can be expected into the evening hours. ...Middle Atlantic Region... Dominant surface anticyclone over southeastern Canada will shift across ON/QC, which will allow a synoptic front to drape itself across the Middle Atlantic during the afternoon. This boundary will focus scattered thunderstorms as convective temperatures are breached by mid afternoon. Wind profiles favor mostly disorganized pulse-multicell updrafts. These storms will move slowly southeast with an attendant risk for wind and perhaps some hail. Robust updrafts will be strongly diurnally driven. ..Darrow/Jirak.. 08/29/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Thu Aug 29 2024 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER/MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Severe thunderstorms are expected across the Upper/Middle Mississippi Valley to the central Plains. A few severe storms also will be possible over portions of the mid-Atlantic region. ...Upper/Middle Mississippi Valley... Southern portions of a strong upper trough, currently located over the northern Rockies, will eject across the Dakotas this afternoon. As 70-80kt 500mb speed max translates through the base of the trough across ND, primary upper low will track across southern AB into northwestern ON during the latter half of the period. Latest model guidance suggests very strong 12hr mid-level height falls just north of the international border, with more modest falls into the upper Mississippi Valley by 29/00z. Strong low-level warm advection will likely prove instrumental in one or more thunderstorm clusters over eastern ND/northwestern MN at the start of the period. LLJ responsible for this activity will shift into northwestern ON during the day, and this warm-advection activity should lift north of the border as well. However, strong boundary-layer heating will occur across eastern NE into extreme southwest MN by early afternoon. This will aid instability, and CINH will begin to weaken along the front, as surface temperatures rise into the mid 80s across central MN. NAM forecast sounding for KLJF at 22z is thermodynamically impressive with MLCAPE around 5400 J/kg and 0-6km shear approaching 30kt. 30-35kt deep-layer shear is expected along the northern extent of the stronger buoyancy. As a result, supercells are expected to develop along/ahead of the cold front, supported aloft by the upstream short wave. Large hail, severe gusts, and a few tornadoes are the expected hazards with these storms. Scattered convection, with a more-isolated severe threat, is forecast along the trailing cold front across the central Plains as readings breach convective temperatures later in the afternoon. Wind profiles at lower latitudes are not very strong, so this activity will be multicellular and less organized. Even so, some risk for hail/wind can be expected into the evening hours. ...Middle Atlantic Region... Dominant surface anticyclone over southeastern Canada will shift across ON/QC, which will allow a synoptic front to drape itself across the Middle Atlantic during the afternoon. This boundary will focus scattered thunderstorms as convective temperatures are breached by mid afternoon. Wind profiles favor mostly disorganized pulse-multicell updrafts. These storms will move slowly southeast with an attendant risk for wind and perhaps some hail. Robust updrafts will be strongly diurnally driven. ..Darrow/Jirak.. 08/29/2024 Read more

MD 2026 CONCERNING TORNADO WATCH 661... FOR PARTS OF NORTH CENTRAL SOUTH DAKOTA AND SOUTH CENTRAL NORTH DAKOTA
Mesoscale Discussion 2026 NWS Storm Prediction Center Norman OK 0941 PM CDT Wed Aug 28 2024 Areas affected...parts of north central South Dakota and south central North Dakota Concerning...Tornado Watch 661... Valid 290241Z - 290445Z The severe weather threat for Tornado Watch 661 continues. SUMMARY...Thunderstorm development, in general, is beginning to weaken, with the risk for tornadoes likely to become increasingly negligible through 10-11 PM CDT. Some risk for severe hail and, perhaps, localized strong wind gusts may persist into the overnight hours across parts of the central and eastern Dakotas. However, a new severe weather watch is not currently anticipated. DISCUSSION...Ongoing convection appears to be undergoing notable weakening trends, including the the isolated supercell just south of the state border vicinity, across eastern Campbell county South Dakota. This has occurred as the loss of daytime heating has resulted in increasing inhibition for the seasonably moist boundary parcels near the surface trough across the central Dakotas. However, forcing associated with strong low-level warm advection may maintain at least a severe hail threat with the Campbell county storm as it accelerates north-northeastward, and becomes increasingly rooted above the boundary layer during the next hour or two. Strongest potential instability remains focused near a weak surface low, centered within the surface trough to the north-northwest of Pierre SD. However, as the slow moving upstream low, now centered over southern Saskatchewan just to the north of the international border, continues east-northeastward, models suggest that warming elevated mixed-layer air will gradually advect across the central North and South Dakota state border area through 04-05Z. As this occurs, the potential for renewed thunderstorm development rooted within the unstable boundary layer is expected to diminish. ..Kerr.. 08/29/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...BIS... LAT...LON 45960044 47149937 46599839 45019952 45030058 45960044 Read more

WW 0661 Status Updates
STATUS REPORT ON WW 661 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SW ABR TO 30 SSE MBG TO 10 WSW MBG TO 10 N MBG TO 35 NE BIS TO 45 WSW DVL. REMAINING VALID PORTION OF WW 661 MAY BE ALLOWED TO EXPIRE AT 29/04Z. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2026. ..KERR..08/29/24 ATTN...WFO...BIS...ABR... STATUS REPORT FOR WT 661 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NDC029-043-047-051-093-103-290400- ND . NORTH DAKOTA COUNTIES INCLUDED ARE EMMONS KIDDER LOGAN MCINTOSH STUTSMAN WELLS SDC021-045-089-129-290400- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CAMPBELL EDMUNDS MCPHERSON WALWORTH 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 Read more

WW 661 TORNADO ND SD 282140Z - 290400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 661 NWS Storm Prediction Center Norman OK 440 PM CDT Wed Aug 28 2024 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of South central North Dakota North central South Dakota * Effective this Wednesday afternoon and evening from 440 PM until 1100 PM CDT. * Primary threats include... A few tornadoes possible Scattered large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging wind gusts to 70 mph possible SUMMARY...Supercell development is expected soon near the central North Dakota/South Dakota border, with additional storm development in the next 1-3 hours farther north and south in the watch area. The storm environment initially favors supercells with tornadoes and very large hail (up to 3 inches in diameter), while some clustering of storms later this evening will lead to some increase in the potential for damaging winds of 60-70 mph. The tornado watch area is approximately along and 60 statute miles east and west of a line from 40 miles east northeast of Garrison ND to 80 miles south southeast of Mobridge SD. 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. && 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 600. Mean storm motion vector 25015. ...Thompson Read more

WW 0661 Status Updates
STATUS REPORT ON WW 661 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 SW ABR TO 35 NNE PIR TO 50 SW MBG TO 10 NNW MBG TO 20 NE BIS TO 50 SE MOT. ..KERR..08/29/24 ATTN...WFO...BIS...ABR... STATUS REPORT FOR WT 661 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NDC029-043-047-051-093-103-290340- ND . NORTH DAKOTA COUNTIES INCLUDED ARE EMMONS KIDDER LOGAN MCINTOSH STUTSMAN WELLS SDC021-031-041-045-049-089-107-129-290340- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CAMPBELL CORSON DEWEY EDMUNDS FAULK MCPHERSON POTTER WALWORTH 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 0661 Status Updates
STATUS REPORT ON WW 661 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 NW PIR TO 10 NNW MBG TO 40 ENE N60. ..KERR..08/29/24 ATTN...WFO...BIS...ABR... STATUS REPORT FOR WT 661 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NDC015-029-043-047-051-083-093-103-290240- ND . NORTH DAKOTA COUNTIES INCLUDED ARE BURLEIGH EMMONS KIDDER LOGAN MCINTOSH SHERIDAN STUTSMAN WELLS SDC021-031-041-045-049-059-065-069-089-107-117-119-129-290240- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE CAMPBELL CORSON DEWEY EDMUNDS FAULK HAND HUGHES HYDE MCPHERSON POTTER STANLEY SULLY WALWORTH 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 Read more

MD 2025 CONCERNING TORNADO WATCH 661... FOR PARTS OF NORTH CENTRAL SOUTH DAKOTA AND SOUTH CENTRAL NORTH DAKOTA
Mesoscale Discussion 2025 NWS Storm Prediction Center Norman OK 0652 PM CDT Wed Aug 28 2024 Areas affected...parts of north central South Dakota and south central North Dakota Concerning...Tornado Watch 661... Valid 282352Z - 290145Z The severe weather threat for Tornado Watch 661 continues. SUMMARY...Supercell development likely will persist near the Dakotas state border vicinity between Jamestown ND and Mobridge SD through 8-9 PM CDT. These storms will pose a continuing risk for large hail in excess of 2 inches in diameter, with at least some further increase in tornadic potential possible. DISCUSSION...Intense thunderstorm initiation has been focused along surface troughing across the central Dakotas, most notably near and just north of the state border vicinity. This is near the nose of stronger surface heating characterized by temperatures approaching 90 F, in the presence of lower/mid 70s F dew points. Coupled with forcing for ascent, this has been sufficient to overcome mid-level inhibition associated with warm and capping elevated mixed-layer air. At least some attempt at upscale growth is underway north of the sustained supercell development to the southwest of Fort Yates, across and north of the Bismarck vicinity. However, the mid-level cold core of the slow moving upstream low, progressing eastward along the central Montana international border area, will remain displaced well to the west of the weak southeastward advancing cold front. Strongest low-level forcing, in the form of lower/mid-tropospheric warm advection, appears likely to remain focused near the North and South Dakota state border area, between Jamestown ND and Mobridge SD, aided by an intensifying southerly low-level jet (to 50+ kt around 850 mb) through 01-02Z. This probably will maintain evolving supercell structures, perhaps within a small upscale growing cluster. Aided by southeasterly inflow of air characterized by CAPE in excess of 3000-4000 J/kg, in the presence of moderate southwesterly deep-layer shear, activity will continue to pose a risk for large hail. As clockwise-curved low-level hodographs slowly enlarge, the potential for tornadoes may still increase a bit further early this evening. ..Kerr.. 08/28/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...BIS... LAT...LON 45870028 46719973 46469867 45609907 45609975 45640042 45870028 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0744 PM CDT Wed Aug 28 2024 Valid 290100Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE DAKOTAS... ...SUMMARY... Severe thunderstorm threat continues across parts of the Dakotas this evening. ...01z Update... Strong mid-level short-wave trough is well evident in satellite imagery, extending from the AB/SK border, south into eastern ID. This feature will shift into eastern MT/WY by the end of the period as a 70kt+ 500mb speed max translates across western ND into southwest MB. Scattered supercells have developed ahead of this short wave from near Minot ND to just north of Mobridge SD. Latest model guidance suggests a weak surface low, or at least a wave, will track northeast along the surface front into southeast ND by 29/12z. Over the next few hours, LLJ will increase across the eastern Dakotas and this should encourage eastward propagation of convection within a concentrated zone of low-level warm advection. Latest diagnostic data suggests ongoing storms are rooted within the main corridor of instability, and peak updraft intensity may linger through 03-04z before a more hostile environment is encountered downstream. Very large hail may be noted for the next hour or two, along with some risk for a tornado, then hail/wind threat will linger into the late-evening hours. ..Darrow.. 08/29/2024 Read more