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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Mon Sep 22 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH TEXAS TO THE OHIO VALLEY... ...SUMMARY... Scattered thunderstorms with occasional damaging wind gusts are expected from south Texas to the Lower Ohio Valley on Wednesday. ...Synopsis... A mid-level trough centered over the Great Lakes is forecast to amplify during the day Wednesday. A weak surface low is forecast to move from the Mid-Mississippi Valley Wednesday morning to the eastern Great Lakes by Thursday morning. ...South Texas... Moderate to strong instability is forecast across South Texas on Wednesday as temperatures warm into the upper 90s ahead of a southward moving cold front. Stronger mid-level flow (and thus shear) should remain farther north, and mid-level lapse rates are forecast to be very weak. However, despite these factors, strong heating and convergence along the front should be sufficient for a few strong to severe storms capable of primarily damaging wind gusts. ...Mid Mississippi Valley to the Lower Ohio Valley... A moderately strong mid-level jet streak will be in place across the Mid-Mississippi Valley with a weak surface low on Wednesday morning. This will result in a favorable kinematic environment from northern Mississippi to the Ohio River during the afternoon and evening on Wednesday. If moderate instability can develop within this zone, an organized severe weather threat may materialize. However, widespread cloudcover from Day 2 convection is currently forecast to limit destabilization across much of the warm sector where mid-level lapse rates will also remain weak. Nonetheless, a moist airmass (dewpoints near 70) will be in place and support some instability ahead of the cold front with minimal surface heating. Therefore, a few strong to locally severe storms may be capable of damaging wind gusts. ..Bentley.. 09/22/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 AM CDT Mon Sep 22 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTH TEXAS TO THE OHIO VALLEY... ...SUMMARY... Scattered thunderstorms with occasional damaging wind gusts are expected from south Texas to the Lower Ohio Valley on Wednesday. ...Synopsis... A mid-level trough centered over the Great Lakes is forecast to amplify during the day Wednesday. A weak surface low is forecast to move from the Mid-Mississippi Valley Wednesday morning to the eastern Great Lakes by Thursday morning. ...South Texas... Moderate to strong instability is forecast across South Texas on Wednesday as temperatures warm into the upper 90s ahead of a southward moving cold front. Stronger mid-level flow (and thus shear) should remain farther north, and mid-level lapse rates are forecast to be very weak. However, despite these factors, strong heating and convergence along the front should be sufficient for a few strong to severe storms capable of primarily damaging wind gusts. ...Mid Mississippi Valley to the Lower Ohio Valley... A moderately strong mid-level jet streak will be in place across the Mid-Mississippi Valley with a weak surface low on Wednesday morning. This will result in a favorable kinematic environment from northern Mississippi to the Ohio River during the afternoon and evening on Wednesday. If moderate instability can develop within this zone, an organized severe weather threat may materialize. However, widespread cloudcover from Day 2 convection is currently forecast to limit destabilization across much of the warm sector where mid-level lapse rates will also remain weak. Nonetheless, a moist airmass (dewpoints near 70) will be in place and support some instability ahead of the cold front with minimal surface heating. Therefore, a few strong to locally severe storms may be capable of damaging wind gusts. ..Bentley.. 09/22/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Sep 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN OKLAHOMA...FAR NORTHEAST TEXAS...AND MUCH OF ARKANSAS... ...SUMMARY... Strong to severe storms are possible from the southern Plains to the Tennessee Valley on Tuesday. Strongest thunderstorm activity is expected across eastern Oklahoma into northeastern Texas and Arkansas, where supercells capable of all severe hazards are possible by afternoon. ...Synopsis... A positively tilted mid-level trough will begin the period across eastern Colorado and shift east through the day to the Missouri Valley region by 12Z Wednesday. A 40 to 50 knot mid-level jet streak associated with overnight convection Monday night across KS/OK will shift east across MO/AR during the day Tuesday and gradually weaken. In its wake, the primary mid-level jet streak will emerge across Oklahoma and strengthen Tuesday night as it moves from Oklahoma into Arkansas. A weak surface low is forecast to be across northwest Oklahoma Tuesday morning. This surface low and its associated cold front will drift slowly east through the day. ...Eastern Oklahoma into much of Arkansas and northeast Texas... A large MCS will likely be ongoing Tuesday morning across eastern Kansas, southwest Missouri, and northeast Oklahoma on the nose of a 40 to 50 knot low-level jet. As the low-level jet weakens during the morning and storms move east of the greatest shear/instability, expect the MCS to weaken. Some isolated damaging wind gusts may persist across northern Arkansas/southern Missouri and into TN/KY, but expect this activity to remain mostly sub-severe. The primary severe weather concern will be Tuesday afternoon/evening across eastern Oklahoma and western Arkansas. Strong instability is forecast across this region in the wake of the morning MCS as cool temperatures aloft overspread low to mid 70s dewpoints. RAP/NAM forecast soundings show only modest heating is necessary to erode inhibition. Therefore, expect additional thunderstorm development during the afternoon along and ahead of the cold front as it moves across Oklahoma. Storm motion orthogonal to the front should favor movement along and perhaps off of the front and into the warm sector. Therefore, all severe hazards will be possible across this region in a favorable environment featuring strong instability, moderate deep-layer shear, and elongating, cyclonically curved hodographs. A conditional, potentially more volatile tornado threat is possible across eastern Oklahoma and western Arkansas if significant destabilization can occur north of any outflow boundary left by morning convection. 03Z RAP/00Z NAM forecast soundings near Fort Smith capture this conditional environment well and would potentially support strong tornadoes. However, this evolution is highly dependent on the evolution of Day 1 convection across Kansas and Oklahoma which still remains unclear. In addition, the time window for this favorable environment would be narrow which also adds conditionality to the risk. This scenario will be monitored closely and a Level 3/Enhanced Risk may be justified in later outlooks if this scenario appears more likely. ...Central Texas... Moderate instability is forecast across central/northern Texas Tuesday afternoon with eroding inhibition by mid-afternoon. Shear will be relatively weak, but will increase during the afternoon/evening as the mid-level jet streak drifts south. The most favorable zone for thunderstorm development will be the triple point where the cold front and dryline intersect across North Texas. However, additional isolated storms may also develop along the dryline and cold front. Isolated large hail and damaging wind gusts will be the primary threat from these storms Tuesday afternoon/evening. ...Tennessee Valley... A weak warm front may be a focus for storm development Tuesday afternoon/evening across western/middle Tennessee as moderate instability develops across the region. Deep-layer shear should remain quite weak (less than 20 knots) as the primary mid-level jet streak remains farther west. However, a few stronger storms capable of damaging wind gusts may develop during the afternoon/evening. ..Bentley.. 09/22/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Sep 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN OKLAHOMA...FAR NORTHEAST TEXAS...AND MUCH OF ARKANSAS... ...SUMMARY... Strong to severe storms are possible from the southern Plains to the Tennessee Valley on Tuesday. Strongest thunderstorm activity is expected across eastern Oklahoma into northeastern Texas and Arkansas, where supercells capable of all severe hazards are possible by afternoon. ...Synopsis... A positively tilted mid-level trough will begin the period across eastern Colorado and shift east through the day to the Missouri Valley region by 12Z Wednesday. A 40 to 50 knot mid-level jet streak associated with overnight convection Monday night across KS/OK will shift east across MO/AR during the day Tuesday and gradually weaken. In its wake, the primary mid-level jet streak will emerge across Oklahoma and strengthen Tuesday night as it moves from Oklahoma into Arkansas. A weak surface low is forecast to be across northwest Oklahoma Tuesday morning. This surface low and its associated cold front will drift slowly east through the day. ...Eastern Oklahoma into much of Arkansas and northeast Texas... A large MCS will likely be ongoing Tuesday morning across eastern Kansas, southwest Missouri, and northeast Oklahoma on the nose of a 40 to 50 knot low-level jet. As the low-level jet weakens during the morning and storms move east of the greatest shear/instability, expect the MCS to weaken. Some isolated damaging wind gusts may persist across northern Arkansas/southern Missouri and into TN/KY, but expect this activity to remain mostly sub-severe. The primary severe weather concern will be Tuesday afternoon/evening across eastern Oklahoma and western Arkansas. Strong instability is forecast across this region in the wake of the morning MCS as cool temperatures aloft overspread low to mid 70s dewpoints. RAP/NAM forecast soundings show only modest heating is necessary to erode inhibition. Therefore, expect additional thunderstorm development during the afternoon along and ahead of the cold front as it moves across Oklahoma. Storm motion orthogonal to the front should favor movement along and perhaps off of the front and into the warm sector. Therefore, all severe hazards will be possible across this region in a favorable environment featuring strong instability, moderate deep-layer shear, and elongating, cyclonically curved hodographs. A conditional, potentially more volatile tornado threat is possible across eastern Oklahoma and western Arkansas if significant destabilization can occur north of any outflow boundary left by morning convection. 03Z RAP/00Z NAM forecast soundings near Fort Smith capture this conditional environment well and would potentially support strong tornadoes. However, this evolution is highly dependent on the evolution of Day 1 convection across Kansas and Oklahoma which still remains unclear. In addition, the time window for this favorable environment would be narrow which also adds conditionality to the risk. This scenario will be monitored closely and a Level 3/Enhanced Risk may be justified in later outlooks if this scenario appears more likely. ...Central Texas... Moderate instability is forecast across central/northern Texas Tuesday afternoon with eroding inhibition by mid-afternoon. Shear will be relatively weak, but will increase during the afternoon/evening as the mid-level jet streak drifts south. The most favorable zone for thunderstorm development will be the triple point where the cold front and dryline intersect across North Texas. However, additional isolated storms may also develop along the dryline and cold front. Isolated large hail and damaging wind gusts will be the primary threat from these storms Tuesday afternoon/evening. ...Tennessee Valley... A weak warm front may be a focus for storm development Tuesday afternoon/evening across western/middle Tennessee as moderate instability develops across the region. Deep-layer shear should remain quite weak (less than 20 knots) as the primary mid-level jet streak remains farther west. However, a few stronger storms capable of damaging wind gusts may develop during the afternoon/evening. ..Bentley.. 09/22/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Sep 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN OKLAHOMA...FAR NORTHEAST TEXAS...AND MUCH OF ARKANSAS... ...SUMMARY... Strong to severe storms are possible from the southern Plains to the Tennessee Valley on Tuesday. Strongest thunderstorm activity is expected across eastern Oklahoma into northeastern Texas and Arkansas, where supercells capable of all severe hazards are possible by afternoon. ...Synopsis... A positively tilted mid-level trough will begin the period across eastern Colorado and shift east through the day to the Missouri Valley region by 12Z Wednesday. A 40 to 50 knot mid-level jet streak associated with overnight convection Monday night across KS/OK will shift east across MO/AR during the day Tuesday and gradually weaken. In its wake, the primary mid-level jet streak will emerge across Oklahoma and strengthen Tuesday night as it moves from Oklahoma into Arkansas. A weak surface low is forecast to be across northwest Oklahoma Tuesday morning. This surface low and its associated cold front will drift slowly east through the day. ...Eastern Oklahoma into much of Arkansas and northeast Texas... A large MCS will likely be ongoing Tuesday morning across eastern Kansas, southwest Missouri, and northeast Oklahoma on the nose of a 40 to 50 knot low-level jet. As the low-level jet weakens during the morning and storms move east of the greatest shear/instability, expect the MCS to weaken. Some isolated damaging wind gusts may persist across northern Arkansas/southern Missouri and into TN/KY, but expect this activity to remain mostly sub-severe. The primary severe weather concern will be Tuesday afternoon/evening across eastern Oklahoma and western Arkansas. Strong instability is forecast across this region in the wake of the morning MCS as cool temperatures aloft overspread low to mid 70s dewpoints. RAP/NAM forecast soundings show only modest heating is necessary to erode inhibition. Therefore, expect additional thunderstorm development during the afternoon along and ahead of the cold front as it moves across Oklahoma. Storm motion orthogonal to the front should favor movement along and perhaps off of the front and into the warm sector. Therefore, all severe hazards will be possible across this region in a favorable environment featuring strong instability, moderate deep-layer shear, and elongating, cyclonically curved hodographs. A conditional, potentially more volatile tornado threat is possible across eastern Oklahoma and western Arkansas if significant destabilization can occur north of any outflow boundary left by morning convection. 03Z RAP/00Z NAM forecast soundings near Fort Smith capture this conditional environment well and would potentially support strong tornadoes. However, this evolution is highly dependent on the evolution of Day 1 convection across Kansas and Oklahoma which still remains unclear. In addition, the time window for this favorable environment would be narrow which also adds conditionality to the risk. This scenario will be monitored closely and a Level 3/Enhanced Risk may be justified in later outlooks if this scenario appears more likely. ...Central Texas... Moderate instability is forecast across central/northern Texas Tuesday afternoon with eroding inhibition by mid-afternoon. Shear will be relatively weak, but will increase during the afternoon/evening as the mid-level jet streak drifts south. The most favorable zone for thunderstorm development will be the triple point where the cold front and dryline intersect across North Texas. However, additional isolated storms may also develop along the dryline and cold front. Isolated large hail and damaging wind gusts will be the primary threat from these storms Tuesday afternoon/evening. ...Tennessee Valley... A weak warm front may be a focus for storm development Tuesday afternoon/evening across western/middle Tennessee as moderate instability develops across the region. Deep-layer shear should remain quite weak (less than 20 knots) as the primary mid-level jet streak remains farther west. However, a few stronger storms capable of damaging wind gusts may develop during the afternoon/evening. ..Bentley.. 09/22/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Mon Sep 22 2025 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN OKLAHOMA...FAR NORTHEAST TEXAS...AND MUCH OF ARKANSAS... ...SUMMARY... Strong to severe storms are possible from the southern Plains to the Tennessee Valley on Tuesday. Strongest thunderstorm activity is expected across eastern Oklahoma into northeastern Texas and Arkansas, where supercells capable of all severe hazards are possible by afternoon. ...Synopsis... A positively tilted mid-level trough will begin the period across eastern Colorado and shift east through the day to the Missouri Valley region by 12Z Wednesday. A 40 to 50 knot mid-level jet streak associated with overnight convection Monday night across KS/OK will shift east across MO/AR during the day Tuesday and gradually weaken. In its wake, the primary mid-level jet streak will emerge across Oklahoma and strengthen Tuesday night as it moves from Oklahoma into Arkansas. A weak surface low is forecast to be across northwest Oklahoma Tuesday morning. This surface low and its associated cold front will drift slowly east through the day. ...Eastern Oklahoma into much of Arkansas and northeast Texas... A large MCS will likely be ongoing Tuesday morning across eastern Kansas, southwest Missouri, and northeast Oklahoma on the nose of a 40 to 50 knot low-level jet. As the low-level jet weakens during the morning and storms move east of the greatest shear/instability, expect the MCS to weaken. Some isolated damaging wind gusts may persist across northern Arkansas/southern Missouri and into TN/KY, but expect this activity to remain mostly sub-severe. The primary severe weather concern will be Tuesday afternoon/evening across eastern Oklahoma and western Arkansas. Strong instability is forecast across this region in the wake of the morning MCS as cool temperatures aloft overspread low to mid 70s dewpoints. RAP/NAM forecast soundings show only modest heating is necessary to erode inhibition. Therefore, expect additional thunderstorm development during the afternoon along and ahead of the cold front as it moves across Oklahoma. Storm motion orthogonal to the front should favor movement along and perhaps off of the front and into the warm sector. Therefore, all severe hazards will be possible across this region in a favorable environment featuring strong instability, moderate deep-layer shear, and elongating, cyclonically curved hodographs. A conditional, potentially more volatile tornado threat is possible across eastern Oklahoma and western Arkansas if significant destabilization can occur north of any outflow boundary left by morning convection. 03Z RAP/00Z NAM forecast soundings near Fort Smith capture this conditional environment well and would potentially support strong tornadoes. However, this evolution is highly dependent on the evolution of Day 1 convection across Kansas and Oklahoma which still remains unclear. In addition, the time window for this favorable environment would be narrow which also adds conditionality to the risk. This scenario will be monitored closely and a Level 3/Enhanced Risk may be justified in later outlooks if this scenario appears more likely. ...Central Texas... Moderate instability is forecast across central/northern Texas Tuesday afternoon with eroding inhibition by mid-afternoon. Shear will be relatively weak, but will increase during the afternoon/evening as the mid-level jet streak drifts south. The most favorable zone for thunderstorm development will be the triple point where the cold front and dryline intersect across North Texas. However, additional isolated storms may also develop along the dryline and cold front. Isolated large hail and damaging wind gusts will be the primary threat from these storms Tuesday afternoon/evening. ...Tennessee Valley... A weak warm front may be a focus for storm development Tuesday afternoon/evening across western/middle Tennessee as moderate instability develops across the region. Deep-layer shear should remain quite weak (less than 20 knots) as the primary mid-level jet streak remains farther west. However, a few stronger storms capable of damaging wind gusts may develop during the afternoon/evening. ..Bentley.. 09/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Mon Sep 22 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN NE INTO WESTERN IA/NORTHWEST MO...AND FROM WESTERN/SOUTHERN KS INTO WESTERN/CENTRAL OK AND THE EASTERN OK/TX PANHANDLES... ...SUMMARY... Severe thunderstorms will be possible this afternoon into tonight across portions of the central/southern Plains and the lower to mid Missouri Valley. Strong storms with locally damaging gusts will also be possible from parts of the Tennessee Valley into the lower Great Lakes. ...Synopsis... A rather complex upper-level pattern will cover the CONUS later today. A compact mid/upper-level low will move across the Upper Great Lakes region, while farther south, a low-amplitude shortwave trough (and possible embedded MCV) will move from the mid MS Valley into the OH Valley. Farther west, a shortwave trough initially over the interior Northwest will dig southeastward toward the central Rockies. At the surface, multiple weak surface lows may develop along a lee trough across parts of the central/southern High Plains. A cold front will move southward across the Upper Midwest and northern/central Plains. ...Central/southern Plains into the Upper Midwest... Steepening midlevel lapse rates atop seasonably rich low-level moisture will result in moderate to strong destabilization this afternoon across a large area from the central/southern Plains into parts of the Upper Midwest. Details regarding the location and coverage of diurnal storm development remain uncertain. At least isolated storms may develop near the southward-moving front from northeast NE into the Upper Midwest, and also potentially farther west and south near a surface trough and in the vicinity of any surface lows. Deep-layer flow will be relatively modest into the early evening, but sufficient to support 25-40 kt of effective shear (with the shear magnitude greater where winds may become locally backed). Initial development could evolve into strong multicells and perhaps a few supercells, with an attendant threat of large hail, localized severe gusts, and possibly a brief tornado. Some clustering will be possible with time, especially from western KS into northern OK, where an increasing low-level jet and the influence of the digging shortwave trough across the central Rockies could foster nocturnal MCS development. Any organized upscale growth would result in an increasing severe-wind threat, along with some brief-tornado potential as low-level SRH increases with time. While uncertainty remains, guidance still generally depicts relative maxima in storm coverage across eastern NE/western IA from late afternoon into the evening, and from southwest KS into northern OK during the evening and overnight. As a result, only minor modifications have been made to the Slight Risk areas. ...TN Valley into the lower Great Lakes... Scattered to numerous thunderstorms are expected later today across parts of the TN/OH Valleys, as a midlevel shortwave trough moves across a moist and uncapped environment. Guidance generally suggests an increase in low/midlevel southwesterly flow compared to yesterday, though deep-layer shear will remain modest and midlevel lapse rates are forecast to again be weak. One or more clusters may evolve and pose a threat for at least isolated damaging wind. If any pockets of stronger heating/destabilization can evolve, and/or MCV-related enhancement to the flow is stronger than currently forecast, then a Slight Risk upgrade may eventually be needed for parts of this region. ...Eastern AZ into NM... High-based convection is forecast to develop across eastern AZ and move across NM during the late afternoon and evening, within a strengthening unidirectional westerly flow regime. Buoyancy is expected to remain limited, but CAM guidance suggests potential for a relatively large outflow to develop and spread across NM, accompanied by strong to locally severe gusts. If confidence increases regarding maintenance of some organized convection associated with this outflow, then wind probabilities may eventually be needed. ..Dean/Squitieri.. 09/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Mon Sep 22 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN NE INTO WESTERN IA/NORTHWEST MO...AND FROM WESTERN/SOUTHERN KS INTO WESTERN/CENTRAL OK AND THE EASTERN OK/TX PANHANDLES... ...SUMMARY... Severe thunderstorms will be possible this afternoon into tonight across portions of the central/southern Plains and the lower to mid Missouri Valley. Strong storms with locally damaging gusts will also be possible from parts of the Tennessee Valley into the lower Great Lakes. ...Synopsis... A rather complex upper-level pattern will cover the CONUS later today. A compact mid/upper-level low will move across the Upper Great Lakes region, while farther south, a low-amplitude shortwave trough (and possible embedded MCV) will move from the mid MS Valley into the OH Valley. Farther west, a shortwave trough initially over the interior Northwest will dig southeastward toward the central Rockies. At the surface, multiple weak surface lows may develop along a lee trough across parts of the central/southern High Plains. A cold front will move southward across the Upper Midwest and northern/central Plains. ...Central/southern Plains into the Upper Midwest... Steepening midlevel lapse rates atop seasonably rich low-level moisture will result in moderate to strong destabilization this afternoon across a large area from the central/southern Plains into parts of the Upper Midwest. Details regarding the location and coverage of diurnal storm development remain uncertain. At least isolated storms may develop near the southward-moving front from northeast NE into the Upper Midwest, and also potentially farther west and south near a surface trough and in the vicinity of any surface lows. Deep-layer flow will be relatively modest into the early evening, but sufficient to support 25-40 kt of effective shear (with the shear magnitude greater where winds may become locally backed). Initial development could evolve into strong multicells and perhaps a few supercells, with an attendant threat of large hail, localized severe gusts, and possibly a brief tornado. Some clustering will be possible with time, especially from western KS into northern OK, where an increasing low-level jet and the influence of the digging shortwave trough across the central Rockies could foster nocturnal MCS development. Any organized upscale growth would result in an increasing severe-wind threat, along with some brief-tornado potential as low-level SRH increases with time. While uncertainty remains, guidance still generally depicts relative maxima in storm coverage across eastern NE/western IA from late afternoon into the evening, and from southwest KS into northern OK during the evening and overnight. As a result, only minor modifications have been made to the Slight Risk areas. ...TN Valley into the lower Great Lakes... Scattered to numerous thunderstorms are expected later today across parts of the TN/OH Valleys, as a midlevel shortwave trough moves across a moist and uncapped environment. Guidance generally suggests an increase in low/midlevel southwesterly flow compared to yesterday, though deep-layer shear will remain modest and midlevel lapse rates are forecast to again be weak. One or more clusters may evolve and pose a threat for at least isolated damaging wind. If any pockets of stronger heating/destabilization can evolve, and/or MCV-related enhancement to the flow is stronger than currently forecast, then a Slight Risk upgrade may eventually be needed for parts of this region. ...Eastern AZ into NM... High-based convection is forecast to develop across eastern AZ and move across NM during the late afternoon and evening, within a strengthening unidirectional westerly flow regime. Buoyancy is expected to remain limited, but CAM guidance suggests potential for a relatively large outflow to develop and spread across NM, accompanied by strong to locally severe gusts. If confidence increases regarding maintenance of some organized convection associated with this outflow, then wind probabilities may eventually be needed. ..Dean/Squitieri.. 09/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Mon Sep 22 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN NE INTO WESTERN IA/NORTHWEST MO...AND FROM WESTERN/SOUTHERN KS INTO WESTERN/CENTRAL OK AND THE EASTERN OK/TX PANHANDLES... ...SUMMARY... Severe thunderstorms will be possible this afternoon into tonight across portions of the central/southern Plains and the lower to mid Missouri Valley. Strong storms with locally damaging gusts will also be possible from parts of the Tennessee Valley into the lower Great Lakes. ...Synopsis... A rather complex upper-level pattern will cover the CONUS later today. A compact mid/upper-level low will move across the Upper Great Lakes region, while farther south, a low-amplitude shortwave trough (and possible embedded MCV) will move from the mid MS Valley into the OH Valley. Farther west, a shortwave trough initially over the interior Northwest will dig southeastward toward the central Rockies. At the surface, multiple weak surface lows may develop along a lee trough across parts of the central/southern High Plains. A cold front will move southward across the Upper Midwest and northern/central Plains. ...Central/southern Plains into the Upper Midwest... Steepening midlevel lapse rates atop seasonably rich low-level moisture will result in moderate to strong destabilization this afternoon across a large area from the central/southern Plains into parts of the Upper Midwest. Details regarding the location and coverage of diurnal storm development remain uncertain. At least isolated storms may develop near the southward-moving front from northeast NE into the Upper Midwest, and also potentially farther west and south near a surface trough and in the vicinity of any surface lows. Deep-layer flow will be relatively modest into the early evening, but sufficient to support 25-40 kt of effective shear (with the shear magnitude greater where winds may become locally backed). Initial development could evolve into strong multicells and perhaps a few supercells, with an attendant threat of large hail, localized severe gusts, and possibly a brief tornado. Some clustering will be possible with time, especially from western KS into northern OK, where an increasing low-level jet and the influence of the digging shortwave trough across the central Rockies could foster nocturnal MCS development. Any organized upscale growth would result in an increasing severe-wind threat, along with some brief-tornado potential as low-level SRH increases with time. While uncertainty remains, guidance still generally depicts relative maxima in storm coverage across eastern NE/western IA from late afternoon into the evening, and from southwest KS into northern OK during the evening and overnight. As a result, only minor modifications have been made to the Slight Risk areas. ...TN Valley into the lower Great Lakes... Scattered to numerous thunderstorms are expected later today across parts of the TN/OH Valleys, as a midlevel shortwave trough moves across a moist and uncapped environment. Guidance generally suggests an increase in low/midlevel southwesterly flow compared to yesterday, though deep-layer shear will remain modest and midlevel lapse rates are forecast to again be weak. One or more clusters may evolve and pose a threat for at least isolated damaging wind. If any pockets of stronger heating/destabilization can evolve, and/or MCV-related enhancement to the flow is stronger than currently forecast, then a Slight Risk upgrade may eventually be needed for parts of this region. ...Eastern AZ into NM... High-based convection is forecast to develop across eastern AZ and move across NM during the late afternoon and evening, within a strengthening unidirectional westerly flow regime. Buoyancy is expected to remain limited, but CAM guidance suggests potential for a relatively large outflow to develop and spread across NM, accompanied by strong to locally severe gusts. If confidence increases regarding maintenance of some organized convection associated with this outflow, then wind probabilities may eventually be needed. ..Dean/Squitieri.. 09/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Mon Sep 22 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN NE INTO WESTERN IA/NORTHWEST MO...AND FROM WESTERN/SOUTHERN KS INTO WESTERN/CENTRAL OK AND THE EASTERN OK/TX PANHANDLES... ...SUMMARY... Severe thunderstorms will be possible this afternoon into tonight across portions of the central/southern Plains and the lower to mid Missouri Valley. Strong storms with locally damaging gusts will also be possible from parts of the Tennessee Valley into the lower Great Lakes. ...Synopsis... A rather complex upper-level pattern will cover the CONUS later today. A compact mid/upper-level low will move across the Upper Great Lakes region, while farther south, a low-amplitude shortwave trough (and possible embedded MCV) will move from the mid MS Valley into the OH Valley. Farther west, a shortwave trough initially over the interior Northwest will dig southeastward toward the central Rockies. At the surface, multiple weak surface lows may develop along a lee trough across parts of the central/southern High Plains. A cold front will move southward across the Upper Midwest and northern/central Plains. ...Central/southern Plains into the Upper Midwest... Steepening midlevel lapse rates atop seasonably rich low-level moisture will result in moderate to strong destabilization this afternoon across a large area from the central/southern Plains into parts of the Upper Midwest. Details regarding the location and coverage of diurnal storm development remain uncertain. At least isolated storms may develop near the southward-moving front from northeast NE into the Upper Midwest, and also potentially farther west and south near a surface trough and in the vicinity of any surface lows. Deep-layer flow will be relatively modest into the early evening, but sufficient to support 25-40 kt of effective shear (with the shear magnitude greater where winds may become locally backed). Initial development could evolve into strong multicells and perhaps a few supercells, with an attendant threat of large hail, localized severe gusts, and possibly a brief tornado. Some clustering will be possible with time, especially from western KS into northern OK, where an increasing low-level jet and the influence of the digging shortwave trough across the central Rockies could foster nocturnal MCS development. Any organized upscale growth would result in an increasing severe-wind threat, along with some brief-tornado potential as low-level SRH increases with time. While uncertainty remains, guidance still generally depicts relative maxima in storm coverage across eastern NE/western IA from late afternoon into the evening, and from southwest KS into northern OK during the evening and overnight. As a result, only minor modifications have been made to the Slight Risk areas. ...TN Valley into the lower Great Lakes... Scattered to numerous thunderstorms are expected later today across parts of the TN/OH Valleys, as a midlevel shortwave trough moves across a moist and uncapped environment. Guidance generally suggests an increase in low/midlevel southwesterly flow compared to yesterday, though deep-layer shear will remain modest and midlevel lapse rates are forecast to again be weak. One or more clusters may evolve and pose a threat for at least isolated damaging wind. If any pockets of stronger heating/destabilization can evolve, and/or MCV-related enhancement to the flow is stronger than currently forecast, then a Slight Risk upgrade may eventually be needed for parts of this region. ...Eastern AZ into NM... High-based convection is forecast to develop across eastern AZ and move across NM during the late afternoon and evening, within a strengthening unidirectional westerly flow regime. Buoyancy is expected to remain limited, but CAM guidance suggests potential for a relatively large outflow to develop and spread across NM, accompanied by strong to locally severe gusts. If confidence increases regarding maintenance of some organized convection associated with this outflow, then wind probabilities may eventually be needed. ..Dean/Squitieri.. 09/22/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Mon Sep 22 2025 Valid 221200Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN NE INTO WESTERN IA/NORTHWEST MO...AND FROM WESTERN/SOUTHERN KS INTO WESTERN/CENTRAL OK AND THE EASTERN OK/TX PANHANDLES... ...SUMMARY... Severe thunderstorms will be possible this afternoon into tonight across portions of the central/southern Plains and the lower to mid Missouri Valley. Strong storms with locally damaging gusts will also be possible from parts of the Tennessee Valley into the lower Great Lakes. ...Synopsis... A rather complex upper-level pattern will cover the CONUS later today. A compact mid/upper-level low will move across the Upper Great Lakes region, while farther south, a low-amplitude shortwave trough (and possible embedded MCV) will move from the mid MS Valley into the OH Valley. Farther west, a shortwave trough initially over the interior Northwest will dig southeastward toward the central Rockies. At the surface, multiple weak surface lows may develop along a lee trough across parts of the central/southern High Plains. A cold front will move southward across the Upper Midwest and northern/central Plains. ...Central/southern Plains into the Upper Midwest... Steepening midlevel lapse rates atop seasonably rich low-level moisture will result in moderate to strong destabilization this afternoon across a large area from the central/southern Plains into parts of the Upper Midwest. Details regarding the location and coverage of diurnal storm development remain uncertain. At least isolated storms may develop near the southward-moving front from northeast NE into the Upper Midwest, and also potentially farther west and south near a surface trough and in the vicinity of any surface lows. Deep-layer flow will be relatively modest into the early evening, but sufficient to support 25-40 kt of effective shear (with the shear magnitude greater where winds may become locally backed). Initial development could evolve into strong multicells and perhaps a few supercells, with an attendant threat of large hail, localized severe gusts, and possibly a brief tornado. Some clustering will be possible with time, especially from western KS into northern OK, where an increasing low-level jet and the influence of the digging shortwave trough across the central Rockies could foster nocturnal MCS development. Any organized upscale growth would result in an increasing severe-wind threat, along with some brief-tornado potential as low-level SRH increases with time. While uncertainty remains, guidance still generally depicts relative maxima in storm coverage across eastern NE/western IA from late afternoon into the evening, and from southwest KS into northern OK during the evening and overnight. As a result, only minor modifications have been made to the Slight Risk areas. ...TN Valley into the lower Great Lakes... Scattered to numerous thunderstorms are expected later today across parts of the TN/OH Valleys, as a midlevel shortwave trough moves across a moist and uncapped environment. Guidance generally suggests an increase in low/midlevel southwesterly flow compared to yesterday, though deep-layer shear will remain modest and midlevel lapse rates are forecast to again be weak. One or more clusters may evolve and pose a threat for at least isolated damaging wind. If any pockets of stronger heating/destabilization can evolve, and/or MCV-related enhancement to the flow is stronger than currently forecast, then a Slight Risk upgrade may eventually be needed for parts of this region. ...Eastern AZ into NM... High-based convection is forecast to develop across eastern AZ and move across NM during the late afternoon and evening, within a strengthening unidirectional westerly flow regime. Buoyancy is expected to remain limited, but CAM guidance suggests potential for a relatively large outflow to develop and spread across NM, accompanied by strong to locally severe gusts. If confidence increases regarding maintenance of some organized convection associated with this outflow, then wind probabilities may eventually be needed. ..Dean/Squitieri.. 09/22/2025 Read more

462
ABPZ20 KNHC 220533
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sun Sep 21 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Narda, located a couple of hundred miles south of the southern
coast of Mexico.

Tropical cyclone formation is not expected during the next 7 days.

&&

Public Advisories on Tropical Storm Narda are issued under WMO
header WTPZ34 KNHC and under AWIPS header MIATCPEP4.
Forecast/Advisories on Tropical Storm Narda are issued under WMO
header WTPZ24 KNHC and under AWIPS header MIATCMEP4.

$$
Forecaster Jelsema

New Hampshire has a statewide ban on open fires and smoking in or near wooded areas starting Monday, September 22 under a proclamation issued by Gov. Kelly Ayotte. The state was facing severe drought and facing the potential for large, dangerous wildfires. New Hampshire has also suspended its online fire permit system until the drought eases. My Keene Now (N.H.), Sep 22, 2025

The South Berwick Water District issued a water emergency declaration banning outdoor water use and encouraging water conservation indoors. Below normal rainfall over the long term and high temperatures have strained water resources. The water district noted that some of their supplies had not yet recovered from drought in 2022. WCSH TV 6 News Center Maine (Portland, Maine), Aug 12, 2025

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1050 PM CDT Sun Sep 21 2025 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A broad, positively tilted mid-level trough will progress across the southern Plains/Mid-Mississippi Valley tomorrow (Tuesday). Surface high pressure will continue to build across the Interior West, as lee surface troughing and an associated moist low-level airmass prevails east of the Rockies. Similar to Day 1, the aforementioned conditions will limit significant, widespread wildfire growth. ..Squitieri.. 09/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1050 PM CDT Sun Sep 21 2025 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A broad, positively tilted mid-level trough will progress across the southern Plains/Mid-Mississippi Valley tomorrow (Tuesday). Surface high pressure will continue to build across the Interior West, as lee surface troughing and an associated moist low-level airmass prevails east of the Rockies. Similar to Day 1, the aforementioned conditions will limit significant, widespread wildfire growth. ..Squitieri.. 09/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1050 PM CDT Sun Sep 21 2025 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A broad, positively tilted mid-level trough will progress across the southern Plains/Mid-Mississippi Valley tomorrow (Tuesday). Surface high pressure will continue to build across the Interior West, as lee surface troughing and an associated moist low-level airmass prevails east of the Rockies. Similar to Day 1, the aforementioned conditions will limit significant, widespread wildfire growth. ..Squitieri.. 09/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1050 PM CDT Sun Sep 21 2025 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A broad, positively tilted mid-level trough will progress across the southern Plains/Mid-Mississippi Valley tomorrow (Tuesday). Surface high pressure will continue to build across the Interior West, as lee surface troughing and an associated moist low-level airmass prevails east of the Rockies. Similar to Day 1, the aforementioned conditions will limit significant, widespread wildfire growth. ..Squitieri.. 09/22/2025 ...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 1049 PM CDT Sun Sep 21 2025 Valid 221200Z - 231200Z ...NO CRITICAL AREAS... ...Synopsis... A series of mid-level troughs will progress across the Rockies into the Midwest and Northeast today. Surface high pressure will dominate the Interior West, while lee surface troughing will encourage the northward transport of a moist low-level airmass to much of the U.S. east of the Rockies. The net result will be quiescent fire weather conditions across much of the CONUS. ..Squitieri.. 09/22/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more