Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CDT Tue Sep 09 2025 Valid 111200Z - 121200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN SOUTH DAKOTA...MUCH OF NORTH DAKOTA...AND EASTERN MONTANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible across Montana and the Dakotas on Thursday. Additional isolated storms are possible across the southern High Plains and Intermountain West. ...Discussion... Persistent southwesterly flow across the Rockies will maintain persistent lee troughing across the central/northern High Plains. East of this lee trough, a large reservoir of low to mid 60s dewpoints will be present across the Plains which will lead to moderate instability from Kansas to the Canadian border. Isolated thunderstorms may be possible by Thursday afternoon as inhibition erodes along this trough axis. Organized thunderstorms will be most likely from southwest South Dakota to western North Dakota/eastern Montana where stronger mid-level flow and weak height falls will be present. Very steep mid-level lapse rates and somewhat dry low-levels will support the potential for large hail some severe wind gust threat. Overall, weak forcing may keep storm coverage isolated. However, if greater storm coverage occurs, a hail driven Slight Risk may be warranted given at least marginal supercell wind profiles across the region. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Tue Sep 09 2025 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered showers and thunderstorms are possible over parts of the Northwest and northern Rockies with more isolated storms over the High Plains Wednesday. A stronger storm or two is possible, but severe potential is overall low. ...Synopsis... An upper-level ridge will strengthen across the central CONUS on Wednesday with a trough across the West Coast and a deepening trough in the Great Lakes. Surface high pressure will dominate much of the eastern CONUS with low pressure across the Great Basin and weak lee troughing across the High Plains. ...Discussion... A dry, continental airmass will keep convection suppressed across much of the eastern CONUS. Widespread convection is anticipated across the Northwest, northern Great Basin, and the Southwest into the Central Rockies in the diffluent region ahead of the mid-level trough. These storms will be somewhat dry in nature with PWAT values around 0.5 to 0.75 inches and steep low-level lapse rates. Therefore, a few stronger downbursts are possible with isolated severe wind gusts. However, relatively weak instability should limit the overall severe potential across the west. Greater instability will exist across the Plains, but building heights aloft will likely keep storm coverage somewhat isolated. A remnant MCS from Day 1 convection across western Kansas may persist into the morning hours, but should be weakening through the morning as it moves east of the low-level jet axis. Some guidance, such as the NAM, shows significant augmentation of the mid-level height field which could suppress heights enough for isolated thunderstorm activity near the remnant outflow/MCV from morning convection on Wednesday afternoon. However, this scenario is uncertain, and even if it does occur, shear will likely be relatively weak and therefore, any severe threat should be isolated. ..Bentley.. 09/09/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1149 AM CDT Tue Sep 09 2025 Valid 091700Z - 101200Z ...Washington State... Some retractions were made to the southeastern extent of the isolated dry thunderstorm area across eastern WA. The minor changes were based on recent rainfall and distribution of ongoing convection across the Columbia Basin. A mix of wet and dry thunderstorms are anticipated this afternoon across the Washington Cascades and higher terrain of northeastern WA. Pockets of drier, heavier fuels could still be receptive to new ignitions through today outside of heavier rain cores. ..Williams.. 09/09/2025 .PREV DISCUSSION... /ISSUED 1254 AM CDT Tue Sep 09 2025/ ...Synopsis... An upper-level trough will continue to make slow eastward progress today. Stronger mid-level winds will push into the southern and eastern Great Basin. Farther north and west, lift from the upper low will promote widely scattered to scattered showers and thunderstorms in parts of the Northwest and northern Rockies. ...Northwest/northern Rockies... Thunderstorms are possible periodically in the Northwest. Portions of the Columbia Basin may see storms both in the morning and overnight tonight. Most areas have had recent precipitation and fuels indices have been trending toward lower fire weather concerns. However, there are pockets of remaining dry fuels in the Columbia Basin where there will be some concern for lightning ignitions. ...Southern/eastern Great Basin... With the stronger mid-level winds overspreading the region, 15-20 mph winds (locally up to 25 mph) can be expected in southern/eastern Nevada into western Utah. RH could locally dip as low as 10-15%, but 15-20% will be more common. Given the current state of fuels, elevated conditions will likely be localized in nature. ...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 1149 AM CDT Tue Sep 09 2025 Valid 091700Z - 101200Z ...Washington State... Some retractions were made to the southeastern extent of the isolated dry thunderstorm area across eastern WA. The minor changes were based on recent rainfall and distribution of ongoing convection across the Columbia Basin. A mix of wet and dry thunderstorms are anticipated this afternoon across the Washington Cascades and higher terrain of northeastern WA. Pockets of drier, heavier fuels could still be receptive to new ignitions through today outside of heavier rain cores. ..Williams.. 09/09/2025 .PREV DISCUSSION... /ISSUED 1254 AM CDT Tue Sep 09 2025/ ...Synopsis... An upper-level trough will continue to make slow eastward progress today. Stronger mid-level winds will push into the southern and eastern Great Basin. Farther north and west, lift from the upper low will promote widely scattered to scattered showers and thunderstorms in parts of the Northwest and northern Rockies. ...Northwest/northern Rockies... Thunderstorms are possible periodically in the Northwest. Portions of the Columbia Basin may see storms both in the morning and overnight tonight. Most areas have had recent precipitation and fuels indices have been trending toward lower fire weather concerns. However, there are pockets of remaining dry fuels in the Columbia Basin where there will be some concern for lightning ignitions. ...Southern/eastern Great Basin... With the stronger mid-level winds overspreading the region, 15-20 mph winds (locally up to 25 mph) can be expected in southern/eastern Nevada into western Utah. RH could locally dip as low as 10-15%, but 15-20% will be more common. Given the current state of fuels, elevated conditions will likely be localized in nature. ...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 1149 AM CDT Tue Sep 09 2025 Valid 091700Z - 101200Z ...Washington State... Some retractions were made to the southeastern extent of the isolated dry thunderstorm area across eastern WA. The minor changes were based on recent rainfall and distribution of ongoing convection across the Columbia Basin. A mix of wet and dry thunderstorms are anticipated this afternoon across the Washington Cascades and higher terrain of northeastern WA. Pockets of drier, heavier fuels could still be receptive to new ignitions through today outside of heavier rain cores. ..Williams.. 09/09/2025 .PREV DISCUSSION... /ISSUED 1254 AM CDT Tue Sep 09 2025/ ...Synopsis... An upper-level trough will continue to make slow eastward progress today. Stronger mid-level winds will push into the southern and eastern Great Basin. Farther north and west, lift from the upper low will promote widely scattered to scattered showers and thunderstorms in parts of the Northwest and northern Rockies. ...Northwest/northern Rockies... Thunderstorms are possible periodically in the Northwest. Portions of the Columbia Basin may see storms both in the morning and overnight tonight. Most areas have had recent precipitation and fuels indices have been trending toward lower fire weather concerns. However, there are pockets of remaining dry fuels in the Columbia Basin where there will be some concern for lightning ignitions. ...Southern/eastern Great Basin... With the stronger mid-level winds overspreading the region, 15-20 mph winds (locally up to 25 mph) can be expected in southern/eastern Nevada into western Utah. RH could locally dip as low as 10-15%, but 15-20% will be more common. Given the current state of fuels, elevated conditions will likely be localized in nature. ...Please see www.spc.noaa.gov/fire for graphic product... Read more