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SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Sun Feb 25 2024 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Monday. ...Synopsis... Across the West, an upper-level trough initially over the Pacific Northwest is forecast to move east-southeastward through the day. An upper-level low initially off of the Baja California coast is forecast to evolve into an open wave and begin moving eastward, in response to the digging trough to the north. Weak convection related to these troughs will be possible across much of the West. At this time, the greatest relative threat of sporadic lightning flashes is expected near the Pacific Northwest coast (supported by very cold temperatures aloft), eastern Great Basin into the central Rockies (as ascent spreads east-southeastward with the upper trough), and in the vicinity of the Channel Islands offshore of southern CA (associated with the southernmost ejecting trough). Farther east, MUCAPE may increase into the 500-1500 J/kg range Monday night from eastern portions of the southern Plains into parts of the MS/OH Valleys and Great Lakes region, related to modest moisture return beneath steepening midlevel lapse rates. However, with moisture quality expected to be lackluster and large-scale ascent rather nebulous, lingering MUCINH may preclude vigorous deep convection across most of the region. A broad general thunderstorm area has been maintained with this outlook, though confidence is low regarding coverage and favored location of nocturnal storm development. If deep convection can be sustained overnight, then a strong storm or two capable of at least small hail could evolve prior to the end of the forecast period. ..Dean.. 02/25/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Sun Feb 25 2024 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Monday. ...Synopsis... Across the West, an upper-level trough initially over the Pacific Northwest is forecast to move east-southeastward through the day. An upper-level low initially off of the Baja California coast is forecast to evolve into an open wave and begin moving eastward, in response to the digging trough to the north. Weak convection related to these troughs will be possible across much of the West. At this time, the greatest relative threat of sporadic lightning flashes is expected near the Pacific Northwest coast (supported by very cold temperatures aloft), eastern Great Basin into the central Rockies (as ascent spreads east-southeastward with the upper trough), and in the vicinity of the Channel Islands offshore of southern CA (associated with the southernmost ejecting trough). Farther east, MUCAPE may increase into the 500-1500 J/kg range Monday night from eastern portions of the southern Plains into parts of the MS/OH Valleys and Great Lakes region, related to modest moisture return beneath steepening midlevel lapse rates. However, with moisture quality expected to be lackluster and large-scale ascent rather nebulous, lingering MUCINH may preclude vigorous deep convection across most of the region. A broad general thunderstorm area has been maintained with this outlook, though confidence is low regarding coverage and favored location of nocturnal storm development. If deep convection can be sustained overnight, then a strong storm or two capable of at least small hail could evolve prior to the end of the forecast period. ..Dean.. 02/25/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Sun Feb 25 2024 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Monday. ...Synopsis... Across the West, an upper-level trough initially over the Pacific Northwest is forecast to move east-southeastward through the day. An upper-level low initially off of the Baja California coast is forecast to evolve into an open wave and begin moving eastward, in response to the digging trough to the north. Weak convection related to these troughs will be possible across much of the West. At this time, the greatest relative threat of sporadic lightning flashes is expected near the Pacific Northwest coast (supported by very cold temperatures aloft), eastern Great Basin into the central Rockies (as ascent spreads east-southeastward with the upper trough), and in the vicinity of the Channel Islands offshore of southern CA (associated with the southernmost ejecting trough). Farther east, MUCAPE may increase into the 500-1500 J/kg range Monday night from eastern portions of the southern Plains into parts of the MS/OH Valleys and Great Lakes region, related to modest moisture return beneath steepening midlevel lapse rates. However, with moisture quality expected to be lackluster and large-scale ascent rather nebulous, lingering MUCINH may preclude vigorous deep convection across most of the region. A broad general thunderstorm area has been maintained with this outlook, though confidence is low regarding coverage and favored location of nocturnal storm development. If deep convection can be sustained overnight, then a strong storm or two capable of at least small hail could evolve prior to the end of the forecast period. ..Dean.. 02/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Sat Feb 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may occur Sunday night across parts of coastal/northwest Washington. ...Pacific Northwest... Strong midlevel height falls (180m in 12hr) will spread across the Pacific Northwest later today in advance of a very cold upper trough. Latest model guidance suggests 500mb temperatures will decrease to less than -30C north of the sagging jet. This will encourage lapse rates to steepen such that surface-based parcels should become buoyant, primarily after 06z. Greatest instability will be near the coast where marine-influenced boundary layer may contribute to SBCAPE on the order of 100-200 J/kg. Forecast soundings suggest charge separation is possible as cloud tops could exceed 4km AGL, likely adequate for lightning. Will maintain thunder probabilities along the WA Coast to account for this late-night possibility. ..Darrow/Lyons.. 02/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Sat Feb 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may occur Sunday night across parts of coastal/northwest Washington. ...Pacific Northwest... Strong midlevel height falls (180m in 12hr) will spread across the Pacific Northwest later today in advance of a very cold upper trough. Latest model guidance suggests 500mb temperatures will decrease to less than -30C north of the sagging jet. This will encourage lapse rates to steepen such that surface-based parcels should become buoyant, primarily after 06z. Greatest instability will be near the coast where marine-influenced boundary layer may contribute to SBCAPE on the order of 100-200 J/kg. Forecast soundings suggest charge separation is possible as cloud tops could exceed 4km AGL, likely adequate for lightning. Will maintain thunder probabilities along the WA Coast to account for this late-night possibility. ..Darrow/Lyons.. 02/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Sat Feb 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may occur Sunday night across parts of coastal/northwest Washington. ...Pacific Northwest... Strong midlevel height falls (180m in 12hr) will spread across the Pacific Northwest later today in advance of a very cold upper trough. Latest model guidance suggests 500mb temperatures will decrease to less than -30C north of the sagging jet. This will encourage lapse rates to steepen such that surface-based parcels should become buoyant, primarily after 06z. Greatest instability will be near the coast where marine-influenced boundary layer may contribute to SBCAPE on the order of 100-200 J/kg. Forecast soundings suggest charge separation is possible as cloud tops could exceed 4km AGL, likely adequate for lightning. Will maintain thunder probabilities along the WA Coast to account for this late-night possibility. ..Darrow/Lyons.. 02/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Sat Feb 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may occur Sunday night across parts of coastal/northwest Washington. ...Pacific Northwest... Strong midlevel height falls (180m in 12hr) will spread across the Pacific Northwest later today in advance of a very cold upper trough. Latest model guidance suggests 500mb temperatures will decrease to less than -30C north of the sagging jet. This will encourage lapse rates to steepen such that surface-based parcels should become buoyant, primarily after 06z. Greatest instability will be near the coast where marine-influenced boundary layer may contribute to SBCAPE on the order of 100-200 J/kg. Forecast soundings suggest charge separation is possible as cloud tops could exceed 4km AGL, likely adequate for lightning. Will maintain thunder probabilities along the WA Coast to account for this late-night possibility. ..Darrow/Lyons.. 02/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 PM CST Sat Feb 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms may occur Sunday night across parts of coastal/northwest Washington. ...Pacific Northwest... Strong midlevel height falls (180m in 12hr) will spread across the Pacific Northwest later today in advance of a very cold upper trough. Latest model guidance suggests 500mb temperatures will decrease to less than -30C north of the sagging jet. This will encourage lapse rates to steepen such that surface-based parcels should become buoyant, primarily after 06z. Greatest instability will be near the coast where marine-influenced boundary layer may contribute to SBCAPE on the order of 100-200 J/kg. Forecast soundings suggest charge separation is possible as cloud tops could exceed 4km AGL, likely adequate for lightning. Will maintain thunder probabilities along the WA Coast to account for this late-night possibility. ..Darrow/Lyons.. 02/25/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0612 PM CST Sat Feb 24 2024 Valid 250100Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast the rest of tonight. ...01z Update... Northwesterly flow is deepening across the Carolinas this evening as the primary corridor of low-level convergence focuses offshore in response to the progressive short-wave trough. While a few showers will linger across Coastal Carolinas this evening, the prospect for lightning is lessening with this activity given the weakening low-level lapse rates/buoyancy (nocturnal cooling) and downstream convergence. ..Darrow.. 02/25/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0612 PM CST Sat Feb 24 2024 Valid 250100Z - 251200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast the rest of tonight. ...01z Update... Northwesterly flow is deepening across the Carolinas this evening as the primary corridor of low-level convergence focuses offshore in response to the progressive short-wave trough. While a few showers will linger across Coastal Carolinas this evening, the prospect for lightning is lessening with this activity given the weakening low-level lapse rates/buoyancy (nocturnal cooling) and downstream convergence. ..Darrow.. 02/25/2024 Read more

No watches are valid as of Sat Feb 24 23:31:01 UTC 2024.

No Mesoscale Discussions are in effect as of Sat Feb 24 23:31:01 UTC 2024.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0306 PM CST Sat Feb 24 2024 Valid 261200Z - 031200Z A split-flow upper-level pattern will be present to begin the new week. A trough will be in the process of digging into the Great Basin while southern stream flow remains strong across the southern Rockies. The primary trough is forecast to phase with a weaker southern stream feature over the Plains by midweek. Large-scale ridging will then encompass much of the CONUS as the amplifying trough moves offshore late this coming week. Guidance then suggests general troughing in the West that will slowly shift eastward with time. ...Central/Southern High Plains... The approach of the early-week trough and continued strong southern stream flow across the southern Rockies will promote a moderately strong surface pressure gradient on Monday across the regions. Though mid/high-level cloud cover casts some uncertainty on RH reductions, surface winds of 20-25 mph appear probable with at least a few hours of critically low RH for some areas. Surface winds will also be enhanced across parts of eastern Wyoming into Nebraska, but RH reductions are more uncertain on top of currently low fuel receptiveness. For Tuesday, surface winds ahead of the cold front moving southward will be stronger than Monday. Winds of 20-30 mph can be expected with locally greater speeds possible. Due to increasing cloud cover, temperatures are likely to be cooler, limiting RH reductions. However, given the wind magnitudes, 40% probabilities will be maintained. The cold front will eventually pass and RH will increase rapidly. Guidance is in agreement that this will not occur until early evening. As the cold front passes and the surface high shifts to the east by Thursday, a few days of dry, southerly return flow will be possible across the southern High Plains into parts of the central Plains. The overall synoptic pattern should have some degree of predictability and precipitation in these areas should be minimal/light. However, potential for critical fire weather is uncertain given the lack of stronger large-scale features. These areas will continue to be monitored in the coming days. ..Wendt.. 02/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0306 PM CST Sat Feb 24 2024 Valid 261200Z - 031200Z A split-flow upper-level pattern will be present to begin the new week. A trough will be in the process of digging into the Great Basin while southern stream flow remains strong across the southern Rockies. The primary trough is forecast to phase with a weaker southern stream feature over the Plains by midweek. Large-scale ridging will then encompass much of the CONUS as the amplifying trough moves offshore late this coming week. Guidance then suggests general troughing in the West that will slowly shift eastward with time. ...Central/Southern High Plains... The approach of the early-week trough and continued strong southern stream flow across the southern Rockies will promote a moderately strong surface pressure gradient on Monday across the regions. Though mid/high-level cloud cover casts some uncertainty on RH reductions, surface winds of 20-25 mph appear probable with at least a few hours of critically low RH for some areas. Surface winds will also be enhanced across parts of eastern Wyoming into Nebraska, but RH reductions are more uncertain on top of currently low fuel receptiveness. For Tuesday, surface winds ahead of the cold front moving southward will be stronger than Monday. Winds of 20-30 mph can be expected with locally greater speeds possible. Due to increasing cloud cover, temperatures are likely to be cooler, limiting RH reductions. However, given the wind magnitudes, 40% probabilities will be maintained. The cold front will eventually pass and RH will increase rapidly. Guidance is in agreement that this will not occur until early evening. As the cold front passes and the surface high shifts to the east by Thursday, a few days of dry, southerly return flow will be possible across the southern High Plains into parts of the central Plains. The overall synoptic pattern should have some degree of predictability and precipitation in these areas should be minimal/light. However, potential for critical fire weather is uncertain given the lack of stronger large-scale features. These areas will continue to be monitored in the coming days. ..Wendt.. 02/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0306 PM CST Sat Feb 24 2024 Valid 261200Z - 031200Z A split-flow upper-level pattern will be present to begin the new week. A trough will be in the process of digging into the Great Basin while southern stream flow remains strong across the southern Rockies. The primary trough is forecast to phase with a weaker southern stream feature over the Plains by midweek. Large-scale ridging will then encompass much of the CONUS as the amplifying trough moves offshore late this coming week. Guidance then suggests general troughing in the West that will slowly shift eastward with time. ...Central/Southern High Plains... The approach of the early-week trough and continued strong southern stream flow across the southern Rockies will promote a moderately strong surface pressure gradient on Monday across the regions. Though mid/high-level cloud cover casts some uncertainty on RH reductions, surface winds of 20-25 mph appear probable with at least a few hours of critically low RH for some areas. Surface winds will also be enhanced across parts of eastern Wyoming into Nebraska, but RH reductions are more uncertain on top of currently low fuel receptiveness. For Tuesday, surface winds ahead of the cold front moving southward will be stronger than Monday. Winds of 20-30 mph can be expected with locally greater speeds possible. Due to increasing cloud cover, temperatures are likely to be cooler, limiting RH reductions. However, given the wind magnitudes, 40% probabilities will be maintained. The cold front will eventually pass and RH will increase rapidly. Guidance is in agreement that this will not occur until early evening. As the cold front passes and the surface high shifts to the east by Thursday, a few days of dry, southerly return flow will be possible across the southern High Plains into parts of the central Plains. The overall synoptic pattern should have some degree of predictability and precipitation in these areas should be minimal/light. However, potential for critical fire weather is uncertain given the lack of stronger large-scale features. These areas will continue to be monitored in the coming days. ..Wendt.. 02/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0306 PM CST Sat Feb 24 2024 Valid 261200Z - 031200Z A split-flow upper-level pattern will be present to begin the new week. A trough will be in the process of digging into the Great Basin while southern stream flow remains strong across the southern Rockies. The primary trough is forecast to phase with a weaker southern stream feature over the Plains by midweek. Large-scale ridging will then encompass much of the CONUS as the amplifying trough moves offshore late this coming week. Guidance then suggests general troughing in the West that will slowly shift eastward with time. ...Central/Southern High Plains... The approach of the early-week trough and continued strong southern stream flow across the southern Rockies will promote a moderately strong surface pressure gradient on Monday across the regions. Though mid/high-level cloud cover casts some uncertainty on RH reductions, surface winds of 20-25 mph appear probable with at least a few hours of critically low RH for some areas. Surface winds will also be enhanced across parts of eastern Wyoming into Nebraska, but RH reductions are more uncertain on top of currently low fuel receptiveness. For Tuesday, surface winds ahead of the cold front moving southward will be stronger than Monday. Winds of 20-30 mph can be expected with locally greater speeds possible. Due to increasing cloud cover, temperatures are likely to be cooler, limiting RH reductions. However, given the wind magnitudes, 40% probabilities will be maintained. The cold front will eventually pass and RH will increase rapidly. Guidance is in agreement that this will not occur until early evening. As the cold front passes and the surface high shifts to the east by Thursday, a few days of dry, southerly return flow will be possible across the southern High Plains into parts of the central Plains. The overall synoptic pattern should have some degree of predictability and precipitation in these areas should be minimal/light. However, potential for critical fire weather is uncertain given the lack of stronger large-scale features. These areas will continue to be monitored in the coming days. ..Wendt.. 02/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0306 PM CST Sat Feb 24 2024 Valid 261200Z - 031200Z A split-flow upper-level pattern will be present to begin the new week. A trough will be in the process of digging into the Great Basin while southern stream flow remains strong across the southern Rockies. The primary trough is forecast to phase with a weaker southern stream feature over the Plains by midweek. Large-scale ridging will then encompass much of the CONUS as the amplifying trough moves offshore late this coming week. Guidance then suggests general troughing in the West that will slowly shift eastward with time. ...Central/Southern High Plains... The approach of the early-week trough and continued strong southern stream flow across the southern Rockies will promote a moderately strong surface pressure gradient on Monday across the regions. Though mid/high-level cloud cover casts some uncertainty on RH reductions, surface winds of 20-25 mph appear probable with at least a few hours of critically low RH for some areas. Surface winds will also be enhanced across parts of eastern Wyoming into Nebraska, but RH reductions are more uncertain on top of currently low fuel receptiveness. For Tuesday, surface winds ahead of the cold front moving southward will be stronger than Monday. Winds of 20-30 mph can be expected with locally greater speeds possible. Due to increasing cloud cover, temperatures are likely to be cooler, limiting RH reductions. However, given the wind magnitudes, 40% probabilities will be maintained. The cold front will eventually pass and RH will increase rapidly. Guidance is in agreement that this will not occur until early evening. As the cold front passes and the surface high shifts to the east by Thursday, a few days of dry, southerly return flow will be possible across the southern High Plains into parts of the central Plains. The overall synoptic pattern should have some degree of predictability and precipitation in these areas should be minimal/light. However, potential for critical fire weather is uncertain given the lack of stronger large-scale features. These areas will continue to be monitored in the coming days. ..Wendt.. 02/24/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0120 PM CST Sat Feb 24 2024 Valid 242000Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms remain possible across parts of the Carolinas this afternoon. ...20Z Update... No changes have been made to the prior outlook. ..Gleason.. 02/24/2024 .PREV DISCUSSION... /ISSUED 1017 AM CST Sat Feb 24 2024/ ...Carolinas... A deep upper trough is rotating across the eastern states today, with an associated area of large scale lift and precipitation crossing the Appalachians. Mid-level temperatures are unusually cold across the Mid-Atlantic and Carolinas today, with 500mb temperatures of -28 to -30C. Considerable daytime heating over NC/SC will steepen low-level lapse rates and result in marginal CAPE around peak-heating - despite very meager low level moisture. Most 12z model guidance and machine-learning tools suggest potential for isolated thunderstorms, mainly in the 21-02z period. No severe storms are anticipated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0120 PM CST Sat Feb 24 2024 Valid 242000Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms remain possible across parts of the Carolinas this afternoon. ...20Z Update... No changes have been made to the prior outlook. ..Gleason.. 02/24/2024 .PREV DISCUSSION... /ISSUED 1017 AM CST Sat Feb 24 2024/ ...Carolinas... A deep upper trough is rotating across the eastern states today, with an associated area of large scale lift and precipitation crossing the Appalachians. Mid-level temperatures are unusually cold across the Mid-Atlantic and Carolinas today, with 500mb temperatures of -28 to -30C. Considerable daytime heating over NC/SC will steepen low-level lapse rates and result in marginal CAPE around peak-heating - despite very meager low level moisture. Most 12z model guidance and machine-learning tools suggest potential for isolated thunderstorms, mainly in the 21-02z period. No severe storms are anticipated. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0120 PM CST Sat Feb 24 2024 Valid 242000Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms remain possible across parts of the Carolinas this afternoon. ...20Z Update... No changes have been made to the prior outlook. ..Gleason.. 02/24/2024 .PREV DISCUSSION... /ISSUED 1017 AM CST Sat Feb 24 2024/ ...Carolinas... A deep upper trough is rotating across the eastern states today, with an associated area of large scale lift and precipitation crossing the Appalachians. Mid-level temperatures are unusually cold across the Mid-Atlantic and Carolinas today, with 500mb temperatures of -28 to -30C. Considerable daytime heating over NC/SC will steepen low-level lapse rates and result in marginal CAPE around peak-heating - despite very meager low level moisture. Most 12z model guidance and machine-learning tools suggest potential for isolated thunderstorms, mainly in the 21-02z period. No severe storms are anticipated. Read more