Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sun Jun 15 2025 Valid 151700Z - 161200Z Dry downslope flow east of the Sierra Crest along with dry fuels will contribute to elevated fire weather conditions across far western Nevada this afternoon. Single digit relative humidity along with breezy southwest winds are expected across central/southern Nevada and southwestern Utah. However, mid and upper slope fuelscapes remain largely in green up phase, limiting fire spread potential to lower elevation cured grasses with average fuel loading. ..Williams.. 06/15/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Jun 15 2025/ ...Synopsis... A belt of modest mid-level flow will be positioned over the Great Basin during the day, and strong mixing during the afternoon is expected to bring some of that flow to the surface, resulting in a couple areas of fire weather concerns. An Elevated area was maintained across parts of northwestern Nevada, where RH is expected to be near 5-15% with 15-20 mph surface winds atop dry fuels. Similar atmospheric conditions are expected across eastern Nevada into west-central Utah, however fuels in this region are not as dry. Therefore, have held off on introducing Elevated highlights in this area for now. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sun Jun 15 2025 Valid 151700Z - 161200Z Dry downslope flow east of the Sierra Crest along with dry fuels will contribute to elevated fire weather conditions across far western Nevada this afternoon. Single digit relative humidity along with breezy southwest winds are expected across central/southern Nevada and southwestern Utah. However, mid and upper slope fuelscapes remain largely in green up phase, limiting fire spread potential to lower elevation cured grasses with average fuel loading. ..Williams.. 06/15/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Jun 15 2025/ ...Synopsis... A belt of modest mid-level flow will be positioned over the Great Basin during the day, and strong mixing during the afternoon is expected to bring some of that flow to the surface, resulting in a couple areas of fire weather concerns. An Elevated area was maintained across parts of northwestern Nevada, where RH is expected to be near 5-15% with 15-20 mph surface winds atop dry fuels. Similar atmospheric conditions are expected across eastern Nevada into west-central Utah, however fuels in this region are not as dry. Therefore, have held off on introducing Elevated highlights in this area for now. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sun Jun 15 2025 Valid 151700Z - 161200Z Dry downslope flow east of the Sierra Crest along with dry fuels will contribute to elevated fire weather conditions across far western Nevada this afternoon. Single digit relative humidity along with breezy southwest winds are expected across central/southern Nevada and southwestern Utah. However, mid and upper slope fuelscapes remain largely in green up phase, limiting fire spread potential to lower elevation cured grasses with average fuel loading. ..Williams.. 06/15/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Jun 15 2025/ ...Synopsis... A belt of modest mid-level flow will be positioned over the Great Basin during the day, and strong mixing during the afternoon is expected to bring some of that flow to the surface, resulting in a couple areas of fire weather concerns. An Elevated area was maintained across parts of northwestern Nevada, where RH is expected to be near 5-15% with 15-20 mph surface winds atop dry fuels. Similar atmospheric conditions are expected across eastern Nevada into west-central Utah, however fuels in this region are not as dry. Therefore, have held off on introducing Elevated highlights in this area for now. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sun Jun 15 2025 Valid 151700Z - 161200Z Dry downslope flow east of the Sierra Crest along with dry fuels will contribute to elevated fire weather conditions across far western Nevada this afternoon. Single digit relative humidity along with breezy southwest winds are expected across central/southern Nevada and southwestern Utah. However, mid and upper slope fuelscapes remain largely in green up phase, limiting fire spread potential to lower elevation cured grasses with average fuel loading. ..Williams.. 06/15/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Jun 15 2025/ ...Synopsis... A belt of modest mid-level flow will be positioned over the Great Basin during the day, and strong mixing during the afternoon is expected to bring some of that flow to the surface, resulting in a couple areas of fire weather concerns. An Elevated area was maintained across parts of northwestern Nevada, where RH is expected to be near 5-15% with 15-20 mph surface winds atop dry fuels. Similar atmospheric conditions are expected across eastern Nevada into west-central Utah, however fuels in this region are not as dry. Therefore, have held off on introducing Elevated highlights in this area for now. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1152 AM CDT Sun Jun 15 2025 Valid 151700Z - 161200Z Dry downslope flow east of the Sierra Crest along with dry fuels will contribute to elevated fire weather conditions across far western Nevada this afternoon. Single digit relative humidity along with breezy southwest winds are expected across central/southern Nevada and southwestern Utah. However, mid and upper slope fuelscapes remain largely in green up phase, limiting fire spread potential to lower elevation cured grasses with average fuel loading. ..Williams.. 06/15/2025 .PREV DISCUSSION... /ISSUED 0156 AM CDT Sun Jun 15 2025/ ...Synopsis... A belt of modest mid-level flow will be positioned over the Great Basin during the day, and strong mixing during the afternoon is expected to bring some of that flow to the surface, resulting in a couple areas of fire weather concerns. An Elevated area was maintained across parts of northwestern Nevada, where RH is expected to be near 5-15% with 15-20 mph surface winds atop dry fuels. Similar atmospheric conditions are expected across eastern Nevada into west-central Utah, however fuels in this region are not as dry. Therefore, have held off on introducing Elevated highlights in this area for now. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1299 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF NORTH-CENTRAL TEXAS
Mesoscale Discussion 1299 NWS Storm Prediction Center Norman OK 1014 AM CDT Sun Jun 15 2025 Areas affected...portions of north-central Texas Concerning...Severe potential...Watch unlikely Valid 151514Z - 151715Z Probability of Watch Issuance...5 percent SUMMARY...Occasional strong to severe gusts may persist over the next couple hours before storms weaken. DISCUSSION...A cold pool driven bowing segment continues southward across portions of north-central Texas this morning, with occasional gusts 50-60 mph. Radar velocity continues to indicate strong to severe winds 50-60 kts around 2-5 kft above the ground. Recent reports around 60 mph were noted in Knox County Texas. This line continues to move within a region of strengthening MLCIN across central Texas and is generally expected to weaken through time. As such, a watch will not likely be needed. ..Thornton/Thompson.. 06/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FWD...OUN...SJT...LUB... LAT...LON 33310014 33429988 33399896 33709848 33859828 33849798 33709782 33479774 32719752 32329758 32219787 32019917 32069955 32139979 32199990 32270000 33310014 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Jun 15 2025 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON INTO EARLY TONIGHT FROM CENTRAL/EASTERN MONTANA INTO ADJACENT AREAS OF NORTH DAKOTA...SOUTH DAKOTA AND WYOMING... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...MT to SD/NE through tonight... Moderate buoyancy is expected again this afternoon along and south of a an outflow-reinforced baroclinic zone, in advance of a midlevel shortwave trough (now over WA/OR) that will crest the ridge over MT this evening. Scattered thunderstorm development is expected in the zone of ascent along the baroclinic zone and in advance of the midlevel trough, in concert with the diurnal heating cycle in cloud breaks. MLCAPE of 2000-3000 J/kg, steep midlevel lapse rates and long hodographs will favor supercells with very large hail (2-3 inches in diameter). Clustering of storms through the evening will contribute to an increasing threat for severe outflow winds of 60-80 mph as convection spreads eastward toward the SD/ND/MT border region through tonight. Farther south into the High Plains, the scenario will be similar to the previous two days, with a few storm clusters expected to form east of the higher terrain and spread eastward through late evening. Buoyancy/vertical shear will be sufficient for a couple of supercells with some hail threat, though relatively deep mixing supports upscale growth on outflow interactions, with an attendant threat for severe outflow gusts. ...Southeast SD/northwest IA/southwest MN this afternoon/evening... An MCV from overnight convection will continue to move east-southeastward across southeast SD and northwest IA/southwest MN through this evening. Morning convection across northwest IA has weakened, but residual clouds linger. Some flow enhancement in the low-midlevels on the south side of the MCV, in combination with diurnal destabilization in cloud breaks/steep midlevel lapse rates, could support a cluster of storms with some hail/wind threat later this afternoon/evening. Will re-evaluate this corridor this afternoon, but will maintain MRGL risk given lingering clouds and some uncertainty regarding the magnitude of destabilization. ...NW/central TX today... Merged cold pools with overnight convection in OK continue to spread southward across western north TX, with a history of occasional measured gusts near 60 mph. Daytime heating/destabilization ahead of the cold pool will result in sufficient destabilization for storms to continue to develop southward with the cold pool. However, vertical shear is weakening with time with the loss of the nocturnal low-level jet, so convection organization is expected to slowly diminish over time. Still, the thermodynamic environment and the established cold pool (per surface observations and KDYX radar data) will support the continued potential for occasional strong-severe outflow gusts toward central TX/parts of the Edwards Plateau through the afternoon. ...Mid-Atlantic this afternoon/evening... A front, reinforced by differential heating across southern VA, appears to be mixing slowly northward and could serve as a focus for thunderstorm development this afternoon. Weak enhancement to low-level shear/hodograph curvature along the boundary could support weakly rotating storms with the potential to produce a brief tornado or two. Otherwise, the main concern will be isolated wind damage with largely sub-severe winds where low-level lapse rates steepen this afternoon along and south of the front. ..Thompson/Wendt.. 06/15/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Sun Jun 15 2025 Valid 151300Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Scattered severe thunderstorms capable of producing large to very large hail and swaths of severe/damaging gusts (some 75+ mph) are likely across portions of central/eastern Montana into northeast Wyoming and the western Dakotas this afternoon through tonight. Additional strong to severe thunderstorms may occur across the central/southern Plains, and over parts of Virginia and North Carolina. ...Northern/Central Plains... Ongoing thunderstorms across northeast MT may pose an isolated hail threat this morning. Otherwise, upper ridging will continue to prevail over the Southwest and southern Rockies today, with a subtle mid-level shortwave trough forecast to advance northeastward across the northern Rockies and adjacent High Plains through the period. This feature will likely aid in the development of initially high-based convection over parts of the northern Rockies in MT by early to mid afternoon. Meanwhile, diurnal heating of a fairly moist low-level airmass (surface dewpoints generally in the mid to upper 50s) and steep mid-level lapse rates will foster around 2000-3000 J/kg of MLCAPE through the afternoon across much of central/eastern MT along and south of a convectively reinforced boundary. Modest low-level east-southeasterly flow will veer to west-southwesterly and strengthen with height through mid/upper levels. This will support around 40-50 kt of effective bulk shear and organized convection. Intense thunderstorm development appears increasingly likely across central MT by mid to late afternoon, as large-scale ascent associated with the shortwave trough overspreads the surface warm sector. Given the rather favorable thermodynamic/kinematic environment expected, initial convection will likely be supercellular and pose a threat for large to very large hail potentially up to 2-3 inches in diameter. The Enhanced Risk has been expanded westward some in central MT to account for this expected supercell development, and a 30% area has been included for large hail as well. With time this evening, one or more clusters will likely evolve from the initially discrete activity across eastern MT into parts of northeast WY and the western Dakotas. Steepened low-level lapse rates should aid in efficient mixing of intense downdraft winds to the surface, and swaths of severe/damaging winds should occur as thunderstorms spread eastward through the evening and into early Monday morning. Some of these winds may be significant, with peak gusts potentially reaching up to 70-80 mph on an isolated basis. Isolated to scattered high-based thunderstorms should develop along the surface trough/dryline within a moist low-level upslope flow regime across portions of southeast WY into eastern CO, and perhaps persisting into western NE/KS. This activity will pose a risk of strong to severe outflow winds given a deeply mixed boundary layer and the presence of very steep low-level lapse rates. Isolated hail may also occur where any robust updrafts can be maintained within a modestly sheared environment. ...Southern Plains... Extensive, loosely organized convection is ongoing this morning across much of western/southern OK and vicinity. This activity is being aided by modest low-level warm moist advection associated with a 20-30 kt southwesterly low-level jet. Current expectations are for these thunderstorms to generally weaken through the rest of the morning as the low-level jet gradually weakens. Even so, an isolated threat for strong/gusty winds may persist with these clusters as they spread generally south-southeastward. There may be some chance for either this morning convection or related outflow to regenerate new, robust convection this afternoon across parts of TX. Have expanded the Marginal Risk for wind southward a bit to account for this potential, but in general weak shear should limit convective organization with southward extent. Otherwise, an isolated severe threat may exist with convection that develops across AR this afternoon in proximity to a remnant MCV, and along/east of the surface lee trough/dryline across the southern High Plains. ...Virginia/North Carolina... A low-amplitude mid-level shortwave trough will move eastward across the central/southern Appalachians today. A related weak surface low should develop eastward near the NC/VA border through the afternoon. A moist and unstable airmass will likely be in place across much of NC and southern VA as filtered daytime heating occurs. Poor lapse rates aloft and modest deep-layer shear should limit the overall severe potential across this region. Still, isolated wet microbursts and/or marginally severe hail may occur with the stronger updrafts/cores that can develop this afternoon and early evening. ..Gleason/Kerr.. 06/15/2025 Read more