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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 PM CDT Tue Jun 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHWEST TO THE SOUTHERN HIGH PLAINS AND EASTERN MIDWEST... ...SUMMARY... Isolated severe hail and wind are possible from mid-afternoon Wednesday through early morning Thursday in parts of the Southwest. Isolated damaging winds and marginally severe hail may occur across the eastern Midwest from mid-afternoon to evening. ...Synopsis... A broad, positively tilted trough will dominate much of the weather pattern across the CONUS on Wednesday with a base across the Southwest and a trough axis extending toward the northern Plains. Multiple shortwaves will be embedded within this flow which may result in focused regions of thunderstorms on Wednesday. At the surface, a stalled front will extend from the Great Lakes to Far West Texas. This front will be a focus for storm development Wednesday afternoon/evening. ...Eastern Midwest... Showers and thunderstorms will likely be ongoing along a frontal zone from the Ozarks to the western Great Lakes Wednesday morning. Convergence will be weak through the day as the front/composite outflow slowly shifts east through the period. Weak to potentially moderate instability will develop ahead of the front as temperatures warm into the upper 70s to low 80s with dewpoints in the 60s. Overall forcing will be weak with rising heights aloft and weakening convergence along the frontal zone. Moderate shear will be present through much of the day, but it will be oriented parallel to the frontal zone which is less favorable for sustained severe storms. An environment featuring weak to moderate instability and moderate deep-layer shear will support some isolated large hail and damaging wind gusts. However, a more organized threat does not appear likely. ...Southwest into Southern High Plains... A weak mid-level shortwave trough and associated jet streak will move east across the Southwest on Wednesday. Ahead of this feature, low-level flow will veer and bring low-level moisture northwestward across eastern New Mexico. Weak to potentially moderate instability will develop by mid-day with thunderstorms likely initially over the higher terrain and eventually shifting east. Moderate shear will support the potential for a few supercells capable of large hail and severe wind gusts. These storms may be somewhat on the smaller side given the weaker buoyancy. However, there is a conditional risk for one or two larger/stronger supercells to persist into the evening across the Texas Panhandle if moisture/instability can recover ahead of the storms moving out of New Mexico. Strong shear will be present across southeast New Mexico into Far West Texas beneath the mid-level jet streak. If sufficient instability can develop far enough west into the higher terrain, a few supercells are possible with a primary threat for large hail. ..Bentley.. 06/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 PM CDT Tue Jun 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHWEST TO THE SOUTHERN HIGH PLAINS AND EASTERN MIDWEST... ...SUMMARY... Isolated severe hail and wind are possible from mid-afternoon Wednesday through early morning Thursday in parts of the Southwest. Isolated damaging winds and marginally severe hail may occur across the eastern Midwest from mid-afternoon to evening. ...Synopsis... A broad, positively tilted trough will dominate much of the weather pattern across the CONUS on Wednesday with a base across the Southwest and a trough axis extending toward the northern Plains. Multiple shortwaves will be embedded within this flow which may result in focused regions of thunderstorms on Wednesday. At the surface, a stalled front will extend from the Great Lakes to Far West Texas. This front will be a focus for storm development Wednesday afternoon/evening. ...Eastern Midwest... Showers and thunderstorms will likely be ongoing along a frontal zone from the Ozarks to the western Great Lakes Wednesday morning. Convergence will be weak through the day as the front/composite outflow slowly shifts east through the period. Weak to potentially moderate instability will develop ahead of the front as temperatures warm into the upper 70s to low 80s with dewpoints in the 60s. Overall forcing will be weak with rising heights aloft and weakening convergence along the frontal zone. Moderate shear will be present through much of the day, but it will be oriented parallel to the frontal zone which is less favorable for sustained severe storms. An environment featuring weak to moderate instability and moderate deep-layer shear will support some isolated large hail and damaging wind gusts. However, a more organized threat does not appear likely. ...Southwest into Southern High Plains... A weak mid-level shortwave trough and associated jet streak will move east across the Southwest on Wednesday. Ahead of this feature, low-level flow will veer and bring low-level moisture northwestward across eastern New Mexico. Weak to potentially moderate instability will develop by mid-day with thunderstorms likely initially over the higher terrain and eventually shifting east. Moderate shear will support the potential for a few supercells capable of large hail and severe wind gusts. These storms may be somewhat on the smaller side given the weaker buoyancy. However, there is a conditional risk for one or two larger/stronger supercells to persist into the evening across the Texas Panhandle if moisture/instability can recover ahead of the storms moving out of New Mexico. Strong shear will be present across southeast New Mexico into Far West Texas beneath the mid-level jet streak. If sufficient instability can develop far enough west into the higher terrain, a few supercells are possible with a primary threat for large hail. ..Bentley.. 06/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1213 PM CDT Tue Jun 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTHWEST TO THE SOUTHERN HIGH PLAINS AND EASTERN MIDWEST... ...SUMMARY... Isolated severe hail and wind are possible from mid-afternoon Wednesday through early morning Thursday in parts of the Southwest. Isolated damaging winds and marginally severe hail may occur across the eastern Midwest from mid-afternoon to evening. ...Synopsis... A broad, positively tilted trough will dominate much of the weather pattern across the CONUS on Wednesday with a base across the Southwest and a trough axis extending toward the northern Plains. Multiple shortwaves will be embedded within this flow which may result in focused regions of thunderstorms on Wednesday. At the surface, a stalled front will extend from the Great Lakes to Far West Texas. This front will be a focus for storm development Wednesday afternoon/evening. ...Eastern Midwest... Showers and thunderstorms will likely be ongoing along a frontal zone from the Ozarks to the western Great Lakes Wednesday morning. Convergence will be weak through the day as the front/composite outflow slowly shifts east through the period. Weak to potentially moderate instability will develop ahead of the front as temperatures warm into the upper 70s to low 80s with dewpoints in the 60s. Overall forcing will be weak with rising heights aloft and weakening convergence along the frontal zone. Moderate shear will be present through much of the day, but it will be oriented parallel to the frontal zone which is less favorable for sustained severe storms. An environment featuring weak to moderate instability and moderate deep-layer shear will support some isolated large hail and damaging wind gusts. However, a more organized threat does not appear likely. ...Southwest into Southern High Plains... A weak mid-level shortwave trough and associated jet streak will move east across the Southwest on Wednesday. Ahead of this feature, low-level flow will veer and bring low-level moisture northwestward across eastern New Mexico. Weak to potentially moderate instability will develop by mid-day with thunderstorms likely initially over the higher terrain and eventually shifting east. Moderate shear will support the potential for a few supercells capable of large hail and severe wind gusts. These storms may be somewhat on the smaller side given the weaker buoyancy. However, there is a conditional risk for one or two larger/stronger supercells to persist into the evening across the Texas Panhandle if moisture/instability can recover ahead of the storms moving out of New Mexico. Strong shear will be present across southeast New Mexico into Far West Texas beneath the mid-level jet streak. If sufficient instability can develop far enough west into the higher terrain, a few supercells are possible with a primary threat for large hail. ..Bentley.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Tue Jun 03 2025 Valid 031630Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS INTO THE MIDWEST... ...SUMMARY... Scattered severe thunderstorms are possible from the southern Great Plains to the Midwest. Damaging winds and large hail are the primary concerns. ...Central/Southern Plains into the Midwest... Water-vapor imagery late this morning shows a mid-level shortwave trough over the central Great Plains, embedded within larger upper troughing centered over MT/WY and the Dakotas that extends over much of the north-central U.S. A cold front extends from the western Great Lakes southwestward to a weak low near the OK/KS/TX Panhandle region. An extensive area of showers and thunderstorms exists from KS eastward into the mid MS Valley near the frontal zone. A low-predictability forecast scenario regarding specific details of storm evolution is expected this afternoon into the evening. A relatively weak capping inversion was sampled by the 12 UTC Norman, OK and Fort Worth/Midland, TX raobs (9 to 10 deg C at 700 mb) over the southern Great Plains. Heating in wake of morning convection and related cloud debris will promote a very unstable boundary layer by early to mid afternoon. Expecting a diurnal increase in low-level moisture coincident with the evapotranspiration cycle and lowest 100-mb mean mixing ratios increasing from 14-15 to 16-17 g/kg (translated to surface dewpoints rising from 68-70 to 72-76 deg F). Forecast soundings show 2500-3500 J/kg MLCAPE from southwest MO into central TX. The 12 UTC model run of the NAM appears to be an unrealistic outlier solution showing enhanced low-level shear across OK during the afternoon. As convective inhibition erodes across the southern Great Plains east of a dryline/cold front and south of reinforced outflow draped across southern KS into northern MO, expecting scattered to numerous thunderstorms to develop during the afternoon into the evening period. Severe gusts and large hail appear to be the primary severe hazards. Strong to occasionally severe thunderstorms should continue along the front as it moves into TX Hill Country tonight. An elongated corridor of low-tornado potential will be maintained this outlook update from the southern Great Plains northeastward through the lower MO Valley and into the western Great Lakes. A belt of 40-kt 2 km southwesterly flow will be maintained across western into northern MO and spatially overlapping outflow in the lower MO Valley. Limited heating will temper the overall buoyancy across the northern half of MO into IA, likely tempering the overall severe risk. Additionally, with the line-parallel orientation of the deep-layer shear across this region, the expectation is for a predominantly linear storm mode, with occasional bowing segments capable of producing damaging gusts. ..Smith/Flournoy.. 06/03/2025 Read more