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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Tue Apr 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Severe thunderstorms may develop late Thursday afternoon into Thursday night across parts of the central and southern Great Plains. Large hail, severe wind gusts, and a few tornadoes will all be possible. ...Synopsis... A shortwave trough initially over the Southwest is forecast to take on an increasingly negative tilt as it moves eastward towards the central/southern Plains by Thursday night into Friday morning. In response, a surface low will consolidate and deepen across the central High Plains through the day, before moving northeastward toward northwest KS/southwest NE by Friday morning. An initially stationary surface boundary will move northward as a warm front across the central Plains through the day. Along/south of the warm front, relatively rich low-level moisture will stream northward to the east of a dryline that will become established from the eastern TX Panhandle into western KS and eastern CO. ...Southern/central Great Plains... Coverage of the severe-thunderstorm threat remains somewhat uncertain, but a couple intense supercells are possible by Thursday evening near the dryline from western KS into western OK and the TX/OK Panhandles. Another round of overnight convection will potentially bring the severe threat eastward into a larger portion of the central/southern Plains. The warm sector of the deepening cyclone will likely remain capped for much of the day, though elevated convection may persist from parts of central/eastern KS into eastern OK, to the north of the effective warm front. Increasing moisture beneath steep midlevel lapse rates will support MLCAPE in excess of 2000 J/kg along/east of the dryline, as deep-layer shear strengthens across the region through the day. Ascent attendant to the approaching shortwave trough will begin to impinge upon the warm sector by late afternoon, with isolated supercell development possible near the surface low across southwest KS and southward down the dryline into the TX Panhandle. Very large hail (potentially 2-3 inches in diameter) will likely be the primary initial hazard. A notable increase in low-level flow/shear near and after 00Z will also support a tornado threat with any supercells that can persist into the evening across parts of western KS/OK. While any initial dryline storms may weaken by mid/late evening due to increasing MLCINH with eastward extent, renewed storm development is possible overnight along the Pacific cold front from southwest TX into western/central KS/OK as stronger large-scale ascent overspreads the region. Steep midlevel lapse rates, moderate buoyancy, and strong low-level and deep-layer shear will conditionally support a severe threat with overnight convection across the warm sector, though storm mode may become complex and tend toward a linear evolution with time. Severe wind gusts may become an increasing threat with the nocturnal convection, though hail and a couple tornadoes will also be possible if semi-discrete or embedded supercells can be maintained. ...NE/WY border region into northeast CO... Low-level southeasterly flow will support modest moisture return into parts of northeast CO, southeast WY, and western NE, to the north of the deepening cyclone. Thunderstorm development will be possible near and to the cool side of the effective warm front during the afternoon. While deep-layer shear will be weaker compared to areas farther southeast, steep midlevel lapse rates will support an isolated hail threat. A tornado also cannot be ruled out, if surface-based storms can be maintained within this regime. ..Dean.. 04/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Tue Apr 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Severe thunderstorms may develop late Thursday afternoon into Thursday night across parts of the central and southern Great Plains. Large hail, severe wind gusts, and a few tornadoes will all be possible. ...Synopsis... A shortwave trough initially over the Southwest is forecast to take on an increasingly negative tilt as it moves eastward towards the central/southern Plains by Thursday night into Friday morning. In response, a surface low will consolidate and deepen across the central High Plains through the day, before moving northeastward toward northwest KS/southwest NE by Friday morning. An initially stationary surface boundary will move northward as a warm front across the central Plains through the day. Along/south of the warm front, relatively rich low-level moisture will stream northward to the east of a dryline that will become established from the eastern TX Panhandle into western KS and eastern CO. ...Southern/central Great Plains... Coverage of the severe-thunderstorm threat remains somewhat uncertain, but a couple intense supercells are possible by Thursday evening near the dryline from western KS into western OK and the TX/OK Panhandles. Another round of overnight convection will potentially bring the severe threat eastward into a larger portion of the central/southern Plains. The warm sector of the deepening cyclone will likely remain capped for much of the day, though elevated convection may persist from parts of central/eastern KS into eastern OK, to the north of the effective warm front. Increasing moisture beneath steep midlevel lapse rates will support MLCAPE in excess of 2000 J/kg along/east of the dryline, as deep-layer shear strengthens across the region through the day. Ascent attendant to the approaching shortwave trough will begin to impinge upon the warm sector by late afternoon, with isolated supercell development possible near the surface low across southwest KS and southward down the dryline into the TX Panhandle. Very large hail (potentially 2-3 inches in diameter) will likely be the primary initial hazard. A notable increase in low-level flow/shear near and after 00Z will also support a tornado threat with any supercells that can persist into the evening across parts of western KS/OK. While any initial dryline storms may weaken by mid/late evening due to increasing MLCINH with eastward extent, renewed storm development is possible overnight along the Pacific cold front from southwest TX into western/central KS/OK as stronger large-scale ascent overspreads the region. Steep midlevel lapse rates, moderate buoyancy, and strong low-level and deep-layer shear will conditionally support a severe threat with overnight convection across the warm sector, though storm mode may become complex and tend toward a linear evolution with time. Severe wind gusts may become an increasing threat with the nocturnal convection, though hail and a couple tornadoes will also be possible if semi-discrete or embedded supercells can be maintained. ...NE/WY border region into northeast CO... Low-level southeasterly flow will support modest moisture return into parts of northeast CO, southeast WY, and western NE, to the north of the deepening cyclone. Thunderstorm development will be possible near and to the cool side of the effective warm front during the afternoon. While deep-layer shear will be weaker compared to areas farther southeast, steep midlevel lapse rates will support an isolated hail threat. A tornado also cannot be ruled out, if surface-based storms can be maintained within this regime. ..Dean.. 04/23/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Tue Apr 23 2024 Valid 251200Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTHERN AND CENTRAL GREAT PLAINS... ...SUMMARY... Severe thunderstorms may develop late Thursday afternoon into Thursday night across parts of the central and southern Great Plains. Large hail, severe wind gusts, and a few tornadoes will all be possible. ...Synopsis... A shortwave trough initially over the Southwest is forecast to take on an increasingly negative tilt as it moves eastward towards the central/southern Plains by Thursday night into Friday morning. In response, a surface low will consolidate and deepen across the central High Plains through the day, before moving northeastward toward northwest KS/southwest NE by Friday morning. An initially stationary surface boundary will move northward as a warm front across the central Plains through the day. Along/south of the warm front, relatively rich low-level moisture will stream northward to the east of a dryline that will become established from the eastern TX Panhandle into western KS and eastern CO. ...Southern/central Great Plains... Coverage of the severe-thunderstorm threat remains somewhat uncertain, but a couple intense supercells are possible by Thursday evening near the dryline from western KS into western OK and the TX/OK Panhandles. Another round of overnight convection will potentially bring the severe threat eastward into a larger portion of the central/southern Plains. The warm sector of the deepening cyclone will likely remain capped for much of the day, though elevated convection may persist from parts of central/eastern KS into eastern OK, to the north of the effective warm front. Increasing moisture beneath steep midlevel lapse rates will support MLCAPE in excess of 2000 J/kg along/east of the dryline, as deep-layer shear strengthens across the region through the day. Ascent attendant to the approaching shortwave trough will begin to impinge upon the warm sector by late afternoon, with isolated supercell development possible near the surface low across southwest KS and southward down the dryline into the TX Panhandle. Very large hail (potentially 2-3 inches in diameter) will likely be the primary initial hazard. A notable increase in low-level flow/shear near and after 00Z will also support a tornado threat with any supercells that can persist into the evening across parts of western KS/OK. While any initial dryline storms may weaken by mid/late evening due to increasing MLCINH with eastward extent, renewed storm development is possible overnight along the Pacific cold front from southwest TX into western/central KS/OK as stronger large-scale ascent overspreads the region. Steep midlevel lapse rates, moderate buoyancy, and strong low-level and deep-layer shear will conditionally support a severe threat with overnight convection across the warm sector, though storm mode may become complex and tend toward a linear evolution with time. Severe wind gusts may become an increasing threat with the nocturnal convection, though hail and a couple tornadoes will also be possible if semi-discrete or embedded supercells can be maintained. ...NE/WY border region into northeast CO... Low-level southeasterly flow will support modest moisture return into parts of northeast CO, southeast WY, and western NE, to the north of the deepening cyclone. Thunderstorm development will be possible near and to the cool side of the effective warm front during the afternoon. While deep-layer shear will be weaker compared to areas farther southeast, steep midlevel lapse rates will support an isolated hail threat. A tornado also cannot be ruled out, if surface-based storms can be maintained within this regime. ..Dean.. 04/23/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel trough accompanied by strong southwesterly flow aloft will impinge on the Southwest, where dry antecedent conditions will be in place. This will promote a fairly expansive area of dry/breezy conditions across the region; however, fuels are generally not supportive of large-fire spread at this time. Elsewhere, a limited overlap of warm/dry/breezy conditions will temper fire-weather concerns. ..Weinman.. 04/23/2024 ...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 0129 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel trough accompanied by strong southwesterly flow aloft will impinge on the Southwest, where dry antecedent conditions will be in place. This will promote a fairly expansive area of dry/breezy conditions across the region; however, fuels are generally not supportive of large-fire spread at this time. Elsewhere, a limited overlap of warm/dry/breezy conditions will temper fire-weather concerns. ..Weinman.. 04/23/2024 ...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 0129 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel trough accompanied by strong southwesterly flow aloft will impinge on the Southwest, where dry antecedent conditions will be in place. This will promote a fairly expansive area of dry/breezy conditions across the region; however, fuels are generally not supportive of large-fire spread at this time. Elsewhere, a limited overlap of warm/dry/breezy conditions will temper fire-weather concerns. ..Weinman.. 04/23/2024 ...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 0129 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... ...Synopsis... A low-latitude midlevel trough accompanied by strong southwesterly flow aloft will impinge on the Southwest, where dry antecedent conditions will be in place. This will promote a fairly expansive area of dry/breezy conditions across the region; however, fuels are generally not supportive of large-fire spread at this time. Elsewhere, a limited overlap of warm/dry/breezy conditions will temper fire-weather concerns. ..Weinman.. 04/23/2024 ...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 0128 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ..Weinman.. 04/23/2024 ...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 0128 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ..Weinman.. 04/23/2024 ...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 0128 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ..Weinman.. 04/23/2024 ...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 0128 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ..Weinman.. 04/23/2024 ...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 0128 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...NO CRITICAL AREAS... ...Synopsis... A midlevel trough will advance east-southeastward from the Midwest toward the Northeast through the period, while an upper ridge encompasses much of the West. On the backside of the midlevel trough, a post-frontal air mass will infiltrate the northern and central Plains, where breezy/gusty northerly surface winds are expected. Over portions of southern NE and KS, these winds could briefly overlap 20-30 percent afternoon RH, favoring locally elevated fire-weather conditions -- given receptive fuels across the area. However, these conditions appear too brief and marginal for Elevated highlights at this time. Farther west, dry/breezy conditions are expected across the Southwest during the afternoon. However, fuels are generally not supportive of large fires at this time. ..Weinman.. 04/23/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OKLAHOMA AND WEST TEXAS... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... An upper-level trough initially off of the southern CA/Baja coast is forecast to move inland on Wednesday, reaching the Southwest by Thursday morning. A nearly stationary front is forecast to be draped from west/north TX into parts of the lower MS Valley, with weak surface troughing expected over the central/southern Plains. Across the east, an upper-level trough is forecast to move through parts of the OH Valley into the Mid Atlantic and Northeast, as an attendant cold front sweeps through New England. Low-topped convection with locally gusty winds could accompany the front during the afternoon. ...Parts of the southern Great Plains... An uncertain Marginal Risk has been maintained from parts of west TX into OK, with some adjustments made based on latest guidance. Elevated convection may develop or be ongoing across parts of OK Wednesday morning, within a zone of low-level warm advection along the northeastern fringe of moderate elevated buoyancy. Any such convection will tend to move southeastward through the day, north of stationary front. Steep midlevel lapse rates and marginally supportive effective shear (for convection likely based between 800-700 mb) could support an isolated hail/wind risk with any stronger semi-discrete storms. Farther west, generally weak forcing will likely tend to limit coverage of diurnal surface-based storms. However, rather strong heating and diminishing MLCINH could support isolated development across areas of west/northwest TX near the stationary front, and southward along a weakly convergent surface trough/dryline. Moderate to locally strong buoyancy and sufficient deep-layer shear will result in a conditionally favorable environment, and an isolated supercell or two could evolve if storms can mature, with a threat for hail and localized severe gusts. Finally, another round of elevated convection may develop from northwest TX into OK late Wednesday night into Thursday morning, as deeper moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within this regime. ...Southeast OK toward the ArkLaMiss region... Modest buoyancy may develop near/south of the nearly stationary front from southeast OK into the ArkLaMiss Wednesday afternoon. Elevated convection could spread southeastward north of the boundary through the day within a weak northwesterly flow regime, while isolated diurnal storm development will be possible near the boundary. Uncertainty remains regarding the intensity and coverage of convection across this region, but a strong storm or two cannot be ruled out into early evening. ..Dean.. 04/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OKLAHOMA AND WEST TEXAS... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... An upper-level trough initially off of the southern CA/Baja coast is forecast to move inland on Wednesday, reaching the Southwest by Thursday morning. A nearly stationary front is forecast to be draped from west/north TX into parts of the lower MS Valley, with weak surface troughing expected over the central/southern Plains. Across the east, an upper-level trough is forecast to move through parts of the OH Valley into the Mid Atlantic and Northeast, as an attendant cold front sweeps through New England. Low-topped convection with locally gusty winds could accompany the front during the afternoon. ...Parts of the southern Great Plains... An uncertain Marginal Risk has been maintained from parts of west TX into OK, with some adjustments made based on latest guidance. Elevated convection may develop or be ongoing across parts of OK Wednesday morning, within a zone of low-level warm advection along the northeastern fringe of moderate elevated buoyancy. Any such convection will tend to move southeastward through the day, north of stationary front. Steep midlevel lapse rates and marginally supportive effective shear (for convection likely based between 800-700 mb) could support an isolated hail/wind risk with any stronger semi-discrete storms. Farther west, generally weak forcing will likely tend to limit coverage of diurnal surface-based storms. However, rather strong heating and diminishing MLCINH could support isolated development across areas of west/northwest TX near the stationary front, and southward along a weakly convergent surface trough/dryline. Moderate to locally strong buoyancy and sufficient deep-layer shear will result in a conditionally favorable environment, and an isolated supercell or two could evolve if storms can mature, with a threat for hail and localized severe gusts. Finally, another round of elevated convection may develop from northwest TX into OK late Wednesday night into Thursday morning, as deeper moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within this regime. ...Southeast OK toward the ArkLaMiss region... Modest buoyancy may develop near/south of the nearly stationary front from southeast OK into the ArkLaMiss Wednesday afternoon. Elevated convection could spread southeastward north of the boundary through the day within a weak northwesterly flow regime, while isolated diurnal storm development will be possible near the boundary. Uncertainty remains regarding the intensity and coverage of convection across this region, but a strong storm or two cannot be ruled out into early evening. ..Dean.. 04/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OKLAHOMA AND WEST TEXAS... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... An upper-level trough initially off of the southern CA/Baja coast is forecast to move inland on Wednesday, reaching the Southwest by Thursday morning. A nearly stationary front is forecast to be draped from west/north TX into parts of the lower MS Valley, with weak surface troughing expected over the central/southern Plains. Across the east, an upper-level trough is forecast to move through parts of the OH Valley into the Mid Atlantic and Northeast, as an attendant cold front sweeps through New England. Low-topped convection with locally gusty winds could accompany the front during the afternoon. ...Parts of the southern Great Plains... An uncertain Marginal Risk has been maintained from parts of west TX into OK, with some adjustments made based on latest guidance. Elevated convection may develop or be ongoing across parts of OK Wednesday morning, within a zone of low-level warm advection along the northeastern fringe of moderate elevated buoyancy. Any such convection will tend to move southeastward through the day, north of stationary front. Steep midlevel lapse rates and marginally supportive effective shear (for convection likely based between 800-700 mb) could support an isolated hail/wind risk with any stronger semi-discrete storms. Farther west, generally weak forcing will likely tend to limit coverage of diurnal surface-based storms. However, rather strong heating and diminishing MLCINH could support isolated development across areas of west/northwest TX near the stationary front, and southward along a weakly convergent surface trough/dryline. Moderate to locally strong buoyancy and sufficient deep-layer shear will result in a conditionally favorable environment, and an isolated supercell or two could evolve if storms can mature, with a threat for hail and localized severe gusts. Finally, another round of elevated convection may develop from northwest TX into OK late Wednesday night into Thursday morning, as deeper moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within this regime. ...Southeast OK toward the ArkLaMiss region... Modest buoyancy may develop near/south of the nearly stationary front from southeast OK into the ArkLaMiss Wednesday afternoon. Elevated convection could spread southeastward north of the boundary through the day within a weak northwesterly flow regime, while isolated diurnal storm development will be possible near the boundary. Uncertainty remains regarding the intensity and coverage of convection across this region, but a strong storm or two cannot be ruled out into early evening. ..Dean.. 04/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OKLAHOMA AND WEST TEXAS... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... An upper-level trough initially off of the southern CA/Baja coast is forecast to move inland on Wednesday, reaching the Southwest by Thursday morning. A nearly stationary front is forecast to be draped from west/north TX into parts of the lower MS Valley, with weak surface troughing expected over the central/southern Plains. Across the east, an upper-level trough is forecast to move through parts of the OH Valley into the Mid Atlantic and Northeast, as an attendant cold front sweeps through New England. Low-topped convection with locally gusty winds could accompany the front during the afternoon. ...Parts of the southern Great Plains... An uncertain Marginal Risk has been maintained from parts of west TX into OK, with some adjustments made based on latest guidance. Elevated convection may develop or be ongoing across parts of OK Wednesday morning, within a zone of low-level warm advection along the northeastern fringe of moderate elevated buoyancy. Any such convection will tend to move southeastward through the day, north of stationary front. Steep midlevel lapse rates and marginally supportive effective shear (for convection likely based between 800-700 mb) could support an isolated hail/wind risk with any stronger semi-discrete storms. Farther west, generally weak forcing will likely tend to limit coverage of diurnal surface-based storms. However, rather strong heating and diminishing MLCINH could support isolated development across areas of west/northwest TX near the stationary front, and southward along a weakly convergent surface trough/dryline. Moderate to locally strong buoyancy and sufficient deep-layer shear will result in a conditionally favorable environment, and an isolated supercell or two could evolve if storms can mature, with a threat for hail and localized severe gusts. Finally, another round of elevated convection may develop from northwest TX into OK late Wednesday night into Thursday morning, as deeper moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within this regime. ...Southeast OK toward the ArkLaMiss region... Modest buoyancy may develop near/south of the nearly stationary front from southeast OK into the ArkLaMiss Wednesday afternoon. Elevated convection could spread southeastward north of the boundary through the day within a weak northwesterly flow regime, while isolated diurnal storm development will be possible near the boundary. Uncertainty remains regarding the intensity and coverage of convection across this region, but a strong storm or two cannot be ruled out into early evening. ..Dean.. 04/23/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Tue Apr 23 2024 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF OKLAHOMA AND WEST TEXAS... ...SUMMARY... Strong thunderstorms will be possible on Wednesday across parts of Oklahoma and west Texas. Isolated hail and severe gusts will be the primary hazards. ...Synopsis... An upper-level trough initially off of the southern CA/Baja coast is forecast to move inland on Wednesday, reaching the Southwest by Thursday morning. A nearly stationary front is forecast to be draped from west/north TX into parts of the lower MS Valley, with weak surface troughing expected over the central/southern Plains. Across the east, an upper-level trough is forecast to move through parts of the OH Valley into the Mid Atlantic and Northeast, as an attendant cold front sweeps through New England. Low-topped convection with locally gusty winds could accompany the front during the afternoon. ...Parts of the southern Great Plains... An uncertain Marginal Risk has been maintained from parts of west TX into OK, with some adjustments made based on latest guidance. Elevated convection may develop or be ongoing across parts of OK Wednesday morning, within a zone of low-level warm advection along the northeastern fringe of moderate elevated buoyancy. Any such convection will tend to move southeastward through the day, north of stationary front. Steep midlevel lapse rates and marginally supportive effective shear (for convection likely based between 800-700 mb) could support an isolated hail/wind risk with any stronger semi-discrete storms. Farther west, generally weak forcing will likely tend to limit coverage of diurnal surface-based storms. However, rather strong heating and diminishing MLCINH could support isolated development across areas of west/northwest TX near the stationary front, and southward along a weakly convergent surface trough/dryline. Moderate to locally strong buoyancy and sufficient deep-layer shear will result in a conditionally favorable environment, and an isolated supercell or two could evolve if storms can mature, with a threat for hail and localized severe gusts. Finally, another round of elevated convection may develop from northwest TX into OK late Wednesday night into Thursday morning, as deeper moisture spreads northward in advance of the approaching upper trough. Moderate elevated buoyancy and sufficient effective shear could support an isolated hail threat within this regime. ...Southeast OK toward the ArkLaMiss region... Modest buoyancy may develop near/south of the nearly stationary front from southeast OK into the ArkLaMiss Wednesday afternoon. Elevated convection could spread southeastward north of the boundary through the day within a weak northwesterly flow regime, while isolated diurnal storm development will be possible near the boundary. Uncertainty remains regarding the intensity and coverage of convection across this region, but a strong storm or two cannot be ruled out into early evening. ..Dean.. 04/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST TEXAS... ...SUMMARY... A few severe thunderstorms capable of producing large hail (2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. Additional strong storms producing hail to near 1 inch diameter and 60 mph gusts are possible from southeast Wisconsin and northern Illinois into Lower Michigan. ...Synopsis... An upper shortwave trough will pivot eastward across the Upper Great Lakes to the Northeast today. Meanwhile, upper ridging will be focused over the Rockies. At the surface, an area of elongated low pressure is forecast from Quebec to the Upper MS Valley. A secondary surface low is forecast to develop over the TX Panhandle/South Plains. A cold front will link between these two areas of low pressure, extending from southwest WI to central OK and the TX Panhandle by early/mid afternoon. A prior cold frontal intrusion into the Gulf of Mexico and surface high pressure over the Southeast will limit boundary-layer moisture. However, east/southeasterly low-level trajectories into TX become more south/southwest into OK and the along the surface trough into the Upper Great Lakes will allow for low 60s F dewpoints south (southern Plains) to 40s F dewpoints north (Great Lakes). ...Upper Great Lakes... Stronger large-scale ascent will be focused across WI/Lower MI and vicinity during the afternoon ahead of the surface front and upper shortwave trough. While boundary-layer moisture will remain modest, temperatures aloft are forecast to be quite cool, resulting in very steep midlevel lapse rates. This will foster MLCAPE values generally less than 750 J/kg amid modest effective shear magnitudes greater than 30 kt. This should support isolated strong to severe storms during the afternoon/evening from southeast WI into northern IL/IN and parts of Lower MI. Elongated hodographs and mainly elevated instability coupled with the cold temperatures aloft may support hail to near 1 inch diameter. Steep low-level lapse rates amid a dry boundary-layer also may support locally strong gusts. ...Northwest TX/Southwest OK vicinity... Large-scale ascent will be somewhat nebulous over the region today, but subtle northwest flow aloft amid veering low-level wind profiles will result in 40+ kt effective shear magnitudes. Strong heating in the vicinity of a surface low/triple point and dryline, coupled with steep midlevel lapse rates, will aid in moderate destabilization (MLCAPE around 1500-2000 J/kg possible). This should support a few organized cells during the late afternoon/evening. Elongated forecast hodographs and modest vertical shear through 3 km suggests supercells capable of large hail (2+ inch diameter) are possible. Weak low-level flow and mixing to around 850 mb also indicates some potential for locally strong/severe gusts. While storm coverage is expected to remain isolated, given potential for significant hail (2+ inch diameter), a Slight (level 2 of 5) risk has been included. ..Leitman/Weinman.. 04/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST TEXAS... ...SUMMARY... A few severe thunderstorms capable of producing large hail (2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. Additional strong storms producing hail to near 1 inch diameter and 60 mph gusts are possible from southeast Wisconsin and northern Illinois into Lower Michigan. ...Synopsis... An upper shortwave trough will pivot eastward across the Upper Great Lakes to the Northeast today. Meanwhile, upper ridging will be focused over the Rockies. At the surface, an area of elongated low pressure is forecast from Quebec to the Upper MS Valley. A secondary surface low is forecast to develop over the TX Panhandle/South Plains. A cold front will link between these two areas of low pressure, extending from southwest WI to central OK and the TX Panhandle by early/mid afternoon. A prior cold frontal intrusion into the Gulf of Mexico and surface high pressure over the Southeast will limit boundary-layer moisture. However, east/southeasterly low-level trajectories into TX become more south/southwest into OK and the along the surface trough into the Upper Great Lakes will allow for low 60s F dewpoints south (southern Plains) to 40s F dewpoints north (Great Lakes). ...Upper Great Lakes... Stronger large-scale ascent will be focused across WI/Lower MI and vicinity during the afternoon ahead of the surface front and upper shortwave trough. While boundary-layer moisture will remain modest, temperatures aloft are forecast to be quite cool, resulting in very steep midlevel lapse rates. This will foster MLCAPE values generally less than 750 J/kg amid modest effective shear magnitudes greater than 30 kt. This should support isolated strong to severe storms during the afternoon/evening from southeast WI into northern IL/IN and parts of Lower MI. Elongated hodographs and mainly elevated instability coupled with the cold temperatures aloft may support hail to near 1 inch diameter. Steep low-level lapse rates amid a dry boundary-layer also may support locally strong gusts. ...Northwest TX/Southwest OK vicinity... Large-scale ascent will be somewhat nebulous over the region today, but subtle northwest flow aloft amid veering low-level wind profiles will result in 40+ kt effective shear magnitudes. Strong heating in the vicinity of a surface low/triple point and dryline, coupled with steep midlevel lapse rates, will aid in moderate destabilization (MLCAPE around 1500-2000 J/kg possible). This should support a few organized cells during the late afternoon/evening. Elongated forecast hodographs and modest vertical shear through 3 km suggests supercells capable of large hail (2+ inch diameter) are possible. Weak low-level flow and mixing to around 850 mb also indicates some potential for locally strong/severe gusts. While storm coverage is expected to remain isolated, given potential for significant hail (2+ inch diameter), a Slight (level 2 of 5) risk has been included. ..Leitman/Weinman.. 04/23/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1213 AM CDT Tue Apr 23 2024 Valid 231200Z - 241200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF NORTHWEST TEXAS... ...SUMMARY... A few severe thunderstorms capable of producing large hail (2+ inch diameter) and gusts to 65 mph will be possible this afternoon and evening across northwest Texas. Additional strong storms producing hail to near 1 inch diameter and 60 mph gusts are possible from southeast Wisconsin and northern Illinois into Lower Michigan. ...Synopsis... An upper shortwave trough will pivot eastward across the Upper Great Lakes to the Northeast today. Meanwhile, upper ridging will be focused over the Rockies. At the surface, an area of elongated low pressure is forecast from Quebec to the Upper MS Valley. A secondary surface low is forecast to develop over the TX Panhandle/South Plains. A cold front will link between these two areas of low pressure, extending from southwest WI to central OK and the TX Panhandle by early/mid afternoon. A prior cold frontal intrusion into the Gulf of Mexico and surface high pressure over the Southeast will limit boundary-layer moisture. However, east/southeasterly low-level trajectories into TX become more south/southwest into OK and the along the surface trough into the Upper Great Lakes will allow for low 60s F dewpoints south (southern Plains) to 40s F dewpoints north (Great Lakes). ...Upper Great Lakes... Stronger large-scale ascent will be focused across WI/Lower MI and vicinity during the afternoon ahead of the surface front and upper shortwave trough. While boundary-layer moisture will remain modest, temperatures aloft are forecast to be quite cool, resulting in very steep midlevel lapse rates. This will foster MLCAPE values generally less than 750 J/kg amid modest effective shear magnitudes greater than 30 kt. This should support isolated strong to severe storms during the afternoon/evening from southeast WI into northern IL/IN and parts of Lower MI. Elongated hodographs and mainly elevated instability coupled with the cold temperatures aloft may support hail to near 1 inch diameter. Steep low-level lapse rates amid a dry boundary-layer also may support locally strong gusts. ...Northwest TX/Southwest OK vicinity... Large-scale ascent will be somewhat nebulous over the region today, but subtle northwest flow aloft amid veering low-level wind profiles will result in 40+ kt effective shear magnitudes. Strong heating in the vicinity of a surface low/triple point and dryline, coupled with steep midlevel lapse rates, will aid in moderate destabilization (MLCAPE around 1500-2000 J/kg possible). This should support a few organized cells during the late afternoon/evening. Elongated forecast hodographs and modest vertical shear through 3 km suggests supercells capable of large hail (2+ inch diameter) are possible. Weak low-level flow and mixing to around 850 mb also indicates some potential for locally strong/severe gusts. While storm coverage is expected to remain isolated, given potential for significant hail (2+ inch diameter), a Slight (level 2 of 5) risk has been included. ..Leitman/Weinman.. 04/23/2024 Read more