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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CST Tue Feb 20 2024 Valid 221200Z - 281200Z Periods of dry and windy conditions will be possible through the extended period D3/Thursday and potentially again D6/Sunday to D7/Monday. Poor recovery is likely overnight D2/Wednesday - D3/Thursday across southwestern and far western Texas, with breezy post frontal northwesterly flow overlapping elevated to critical relative humidity again Thursday afternoon. A 40 percent delineation was added with this outlook to cover potential for increased fire spread potential from the southern Trans-Pecos into portions of south-central Texas. An upper-level ridge will build in across the western US with downstream troughing across the east D4/Friday through D6/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. Late D6/Sunday into D7/Monday an upper-level low will begin to phase with the Polar jet stream and move eastward, with a belt of enhanced westerly flow aloft overspreading the Rockies and potential for lee trough development. This pattern will favor a return of windy/dry westerly downslope flow into the central/southern Plains. Low confidence in the evolution of the overall pattern precludes the need to include areas at this time. This threat will be monitored in the coming days. ..Thornton.. 02/20/2024 ...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 0348 PM CST Tue Feb 20 2024 Valid 221200Z - 281200Z Periods of dry and windy conditions will be possible through the extended period D3/Thursday and potentially again D6/Sunday to D7/Monday. Poor recovery is likely overnight D2/Wednesday - D3/Thursday across southwestern and far western Texas, with breezy post frontal northwesterly flow overlapping elevated to critical relative humidity again Thursday afternoon. A 40 percent delineation was added with this outlook to cover potential for increased fire spread potential from the southern Trans-Pecos into portions of south-central Texas. An upper-level ridge will build in across the western US with downstream troughing across the east D4/Friday through D6/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. Late D6/Sunday into D7/Monday an upper-level low will begin to phase with the Polar jet stream and move eastward, with a belt of enhanced westerly flow aloft overspreading the Rockies and potential for lee trough development. This pattern will favor a return of windy/dry westerly downslope flow into the central/southern Plains. Low confidence in the evolution of the overall pattern precludes the need to include areas at this time. This threat will be monitored in the coming days. ..Thornton.. 02/20/2024 ...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 0348 PM CST Tue Feb 20 2024 Valid 221200Z - 281200Z Periods of dry and windy conditions will be possible through the extended period D3/Thursday and potentially again D6/Sunday to D7/Monday. Poor recovery is likely overnight D2/Wednesday - D3/Thursday across southwestern and far western Texas, with breezy post frontal northwesterly flow overlapping elevated to critical relative humidity again Thursday afternoon. A 40 percent delineation was added with this outlook to cover potential for increased fire spread potential from the southern Trans-Pecos into portions of south-central Texas. An upper-level ridge will build in across the western US with downstream troughing across the east D4/Friday through D6/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. Late D6/Sunday into D7/Monday an upper-level low will begin to phase with the Polar jet stream and move eastward, with a belt of enhanced westerly flow aloft overspreading the Rockies and potential for lee trough development. This pattern will favor a return of windy/dry westerly downslope flow into the central/southern Plains. Low confidence in the evolution of the overall pattern precludes the need to include areas at this time. This threat will be monitored in the coming days. ..Thornton.. 02/20/2024 ...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 0348 PM CST Tue Feb 20 2024 Valid 221200Z - 281200Z Periods of dry and windy conditions will be possible through the extended period D3/Thursday and potentially again D6/Sunday to D7/Monday. Poor recovery is likely overnight D2/Wednesday - D3/Thursday across southwestern and far western Texas, with breezy post frontal northwesterly flow overlapping elevated to critical relative humidity again Thursday afternoon. A 40 percent delineation was added with this outlook to cover potential for increased fire spread potential from the southern Trans-Pecos into portions of south-central Texas. An upper-level ridge will build in across the western US with downstream troughing across the east D4/Friday through D6/Sunday. Surface high pressure across the central US will keep winds generally light where the driest conditions are expected in the central and southern high Plains. Late D6/Sunday into D7/Monday an upper-level low will begin to phase with the Polar jet stream and move eastward, with a belt of enhanced westerly flow aloft overspreading the Rockies and potential for lee trough development. This pattern will favor a return of windy/dry westerly downslope flow into the central/southern Plains. Low confidence in the evolution of the overall pattern precludes the need to include areas at this time. This threat will be monitored in the coming days. ..Thornton.. 02/20/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook CORR 1 NWS Storm Prediction Center Norman OK 0332 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z CORRECTED FOR LABELS ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND PORTIONS OF FAR WESTERN TEXAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook CORR 1 NWS Storm Prediction Center Norman OK 0332 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z CORRECTED FOR LABELS ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND PORTIONS OF FAR WESTERN TEXAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook CORR 1 NWS Storm Prediction Center Norman OK 0332 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z CORRECTED FOR LABELS ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND PORTIONS OF FAR WESTERN TEXAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook CORR 1 NWS Storm Prediction Center Norman OK 0332 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z CORRECTED FOR LABELS ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND PORTIONS OF FAR WESTERN TEXAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...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 0154 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...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 0154 PM CST Tue Feb 20 2024 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... Minor updates were made to the D2 Fire Weather Elevated and Critical areas with latest information on fuels and guidance on expected meteorological conditions. The Elevated was expanded further west into New Mexico. Though fuels in this region are currently below the 50th percentile, winds are forecast to be sustained around 20-30 gusting 40-50 mph amid relative humidity reductions to 10-15 percent. Drying of fine fuels should support an increase in fire spread potential, given these conditions. The Critical delineation was shifted further south to the border of Mexico to include Big Bend. Ensemble guidance shows high confidence in sustained Critical conditions continuing into these regions amid ERCs around the 50-60th percentile. Latest fuel guidance indicates that ERCs will approach the 60-70th percentile on Thursday, supporting inclusion of the Critical delineation given favorable meteorological conditions. ..Thornton.. 02/20/2024 .PREV DISCUSSION... /ISSUED 0158 AM CST Tue Feb 20 2024/ ...Synopsis... Elevated to critical fire weather conditions are anticipated on Wednesday across the southern High Plains. The upper wave currently off the southern CA coast is forecast to shift east over the next 48 hours, reaching NM by Wednesday afternoon. Although the trough is currently forecast to de-amplify, broad scale ascent ahead of the wave, coupled with strengthening zonal flow over the southern Rockies, will promote the development of an organized lee cyclone over southeast CO/southwest KS by late afternoon. As this occurs, a broad swath of 20-30 mph west/southwest winds will become established from central NM into western TX. The passage of the mid-level jet should phase favorably with peak heating and maximum boundary-layer depth/mixing. This will foster efficient downward momentum transfer, manifesting as frequent gusts between 40-50 mph across central/eastern NM. Downslope warming/drying will promote RH values in the teens to single digits (possibly as low as 5%) from the Rio Grande to the OK Panhandle. Widespread elevated fire weather conditions are expected with critical conditions likely across eastern NM into western TX. Although the worst meteorological conditions are currently anticipated across eastern NM, fuels across much of the region are currently not overly receptive, based on recent fuel guidance with ERCs at or below the 50th percentile. However, warm, dry, and breezy conditions on Tuesday should promote quick drying of finer fuels that may support a more robust fire weather threat on Wednesday. Regardless, Elevated highlights are warranted given the concerning wind/RH forecast, and more widespread Critical highlights may be needed based on how fuels trend over the next 24 hours. Further south across southeast NM/southwest TX, 30-day rainfall totals are around 10-25% of normal, with persistent drought noted in most drought metrics. Consequently, fuels across this region should be more receptive. Although this region may be displaced from the strongest winds, critical fire weather conditions appear probable. ...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 0151 PM CST Tue Feb 20 2024 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. through tonight. ...20Z Update... Beneath cold mid-level air which continues to spread inland of the Pacific coast, insolation is contributing to pockets of weak boundary-layer destabilization across coastal into interior central California, and portions of the Great Basin into northern Rockies. It still appears that this will lead to isolated to widely scattered weak thunderstorm development by late afternoon, which may persist into early evening before waning. Thereafter, one significant mid-level cold core within the large-scale troughing is still forecast to approach southern California and adjacent northern Baja coastal areas late tonight. This will be accompanied by potential for additional weak thunderstorm development, which could linger beyond 12Z Wednesday. ..Kerr.. 02/20/2024 .PREV DISCUSSION... /ISSUED 1005 AM CST Tue Feb 20 2024/ ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0151 PM CST Tue Feb 20 2024 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. through tonight. ...20Z Update... Beneath cold mid-level air which continues to spread inland of the Pacific coast, insolation is contributing to pockets of weak boundary-layer destabilization across coastal into interior central California, and portions of the Great Basin into northern Rockies. It still appears that this will lead to isolated to widely scattered weak thunderstorm development by late afternoon, which may persist into early evening before waning. Thereafter, one significant mid-level cold core within the large-scale troughing is still forecast to approach southern California and adjacent northern Baja coastal areas late tonight. This will be accompanied by potential for additional weak thunderstorm development, which could linger beyond 12Z Wednesday. ..Kerr.. 02/20/2024 .PREV DISCUSSION... /ISSUED 1005 AM CST Tue Feb 20 2024/ ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0151 PM CST Tue Feb 20 2024 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. through tonight. ...20Z Update... Beneath cold mid-level air which continues to spread inland of the Pacific coast, insolation is contributing to pockets of weak boundary-layer destabilization across coastal into interior central California, and portions of the Great Basin into northern Rockies. It still appears that this will lead to isolated to widely scattered weak thunderstorm development by late afternoon, which may persist into early evening before waning. Thereafter, one significant mid-level cold core within the large-scale troughing is still forecast to approach southern California and adjacent northern Baja coastal areas late tonight. This will be accompanied by potential for additional weak thunderstorm development, which could linger beyond 12Z Wednesday. ..Kerr.. 02/20/2024 .PREV DISCUSSION... /ISSUED 1005 AM CST Tue Feb 20 2024/ ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0151 PM CST Tue Feb 20 2024 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. through tonight. ...20Z Update... Beneath cold mid-level air which continues to spread inland of the Pacific coast, insolation is contributing to pockets of weak boundary-layer destabilization across coastal into interior central California, and portions of the Great Basin into northern Rockies. It still appears that this will lead to isolated to widely scattered weak thunderstorm development by late afternoon, which may persist into early evening before waning. Thereafter, one significant mid-level cold core within the large-scale troughing is still forecast to approach southern California and adjacent northern Baja coastal areas late tonight. This will be accompanied by potential for additional weak thunderstorm development, which could linger beyond 12Z Wednesday. ..Kerr.. 02/20/2024 .PREV DISCUSSION... /ISSUED 1005 AM CST Tue Feb 20 2024/ ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0151 PM CST Tue Feb 20 2024 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. through tonight. ...20Z Update... Beneath cold mid-level air which continues to spread inland of the Pacific coast, insolation is contributing to pockets of weak boundary-layer destabilization across coastal into interior central California, and portions of the Great Basin into northern Rockies. It still appears that this will lead to isolated to widely scattered weak thunderstorm development by late afternoon, which may persist into early evening before waning. Thereafter, one significant mid-level cold core within the large-scale troughing is still forecast to approach southern California and adjacent northern Baja coastal areas late tonight. This will be accompanied by potential for additional weak thunderstorm development, which could linger beyond 12Z Wednesday. ..Kerr.. 02/20/2024 .PREV DISCUSSION... /ISSUED 1005 AM CST Tue Feb 20 2024/ ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CST Tue Feb 20 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY EVENING INTO THURSDAY NIGHT ACROSS PARTS OF SOUTHEASTERN KANSAS...NORTHEASTERN OKLAHOMA AND SOUTHWESTERN MISSOURI... ...SUMMARY... A localized area of strong thunderstorm development is possible across parts of the Ozark Plateau and adjacent Great Plains into middle Mississippi Valley vicinity late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... A significant short wave perturbation, splitting away from one stronger branch of westerlies across the northern mid-latitude eastern Pacific, is forecast to contribute to a deepening cyclone while digging southeastward through this period. As it approaches another branch of stronger westerlies across the southern mid- and subtropical latitudes, models indicate that a downstream perturbation within that stream will accelerate inland across southern California and northern Baja by early Wednesday. A rapid east-northeastward progression is then forecast to continue, through the crest of initially more amplified large-scale mid/upper ridging across the central Great Plains into middle Mississippi/Ozark Plateau by 12Z Thursday. At the same time, downstream large-scale mid-level troughing off the southern Atlantic Seaboard appears likely to remain amplified, with some further amplification southward to the east of the Bahamas possible, with continuing cyclogenesis across the western Atlantic. Northerly flow and subsidence in the wake of this regime has contributed to considerable drying across much of the Gulf Basin into Caribbean. While some modification is ongoing across the southwestern Gulf of Mexico through northwestern Gulf coast vicinity, model forecast soundings indicate that boundary-layer moistening will remain rather modest and shallow, beneath warm and capping layers in the lower/mid-troposphere spreading east of the southern Rockies/Mexican Plateau. ...Ozark Plateau/adjacent Great Plains and Mississippi Valley... It does appear that surface low pressure will deepen to the lee of the southern Rockies, northeastward toward the southern Great Lakes region Wednesday through Wednesday night. This likely will be accompanied by strengthening southerly low-level return flow and at least some moistening. However, if, and exactly where, associated large-scale forcing for ascent and destabilization become sufficient to overcome mid-level inhibition remains unclear based on latest model output. Guidance continues to suggest that any thunderstorm development will probably be rooted within the evolving lower/mid-tropospheric warm advection regime across and east-northeast of the Ozark Plateau vicinity late Wednesday evening through early Thursday, though probabilities at any particular location appear low (on the order of 10-20 percent). It might not be out of the question that initial thunderstorm development could be accompanied by some risk for severe hail somewhere across parts of the Ozark Plateau and adjacent Great Plains/middle Mississippi Valley, but this potential stills seems rather conditional at this point. ..Kerr.. 02/20/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CST Tue Feb 20 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY EVENING INTO THURSDAY NIGHT ACROSS PARTS OF SOUTHEASTERN KANSAS...NORTHEASTERN OKLAHOMA AND SOUTHWESTERN MISSOURI... ...SUMMARY... A localized area of strong thunderstorm development is possible across parts of the Ozark Plateau and adjacent Great Plains into middle Mississippi Valley vicinity late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... A significant short wave perturbation, splitting away from one stronger branch of westerlies across the northern mid-latitude eastern Pacific, is forecast to contribute to a deepening cyclone while digging southeastward through this period. As it approaches another branch of stronger westerlies across the southern mid- and subtropical latitudes, models indicate that a downstream perturbation within that stream will accelerate inland across southern California and northern Baja by early Wednesday. A rapid east-northeastward progression is then forecast to continue, through the crest of initially more amplified large-scale mid/upper ridging across the central Great Plains into middle Mississippi/Ozark Plateau by 12Z Thursday. At the same time, downstream large-scale mid-level troughing off the southern Atlantic Seaboard appears likely to remain amplified, with some further amplification southward to the east of the Bahamas possible, with continuing cyclogenesis across the western Atlantic. Northerly flow and subsidence in the wake of this regime has contributed to considerable drying across much of the Gulf Basin into Caribbean. While some modification is ongoing across the southwestern Gulf of Mexico through northwestern Gulf coast vicinity, model forecast soundings indicate that boundary-layer moistening will remain rather modest and shallow, beneath warm and capping layers in the lower/mid-troposphere spreading east of the southern Rockies/Mexican Plateau. ...Ozark Plateau/adjacent Great Plains and Mississippi Valley... It does appear that surface low pressure will deepen to the lee of the southern Rockies, northeastward toward the southern Great Lakes region Wednesday through Wednesday night. This likely will be accompanied by strengthening southerly low-level return flow and at least some moistening. However, if, and exactly where, associated large-scale forcing for ascent and destabilization become sufficient to overcome mid-level inhibition remains unclear based on latest model output. Guidance continues to suggest that any thunderstorm development will probably be rooted within the evolving lower/mid-tropospheric warm advection regime across and east-northeast of the Ozark Plateau vicinity late Wednesday evening through early Thursday, though probabilities at any particular location appear low (on the order of 10-20 percent). It might not be out of the question that initial thunderstorm development could be accompanied by some risk for severe hail somewhere across parts of the Ozark Plateau and adjacent Great Plains/middle Mississippi Valley, but this potential stills seems rather conditional at this point. ..Kerr.. 02/20/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CST Tue Feb 20 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE WEDNESDAY EVENING INTO THURSDAY NIGHT ACROSS PARTS OF SOUTHEASTERN KANSAS...NORTHEASTERN OKLAHOMA AND SOUTHWESTERN MISSOURI... ...SUMMARY... A localized area of strong thunderstorm development is possible across parts of the Ozark Plateau and adjacent Great Plains into middle Mississippi Valley vicinity late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... A significant short wave perturbation, splitting away from one stronger branch of westerlies across the northern mid-latitude eastern Pacific, is forecast to contribute to a deepening cyclone while digging southeastward through this period. As it approaches another branch of stronger westerlies across the southern mid- and subtropical latitudes, models indicate that a downstream perturbation within that stream will accelerate inland across southern California and northern Baja by early Wednesday. A rapid east-northeastward progression is then forecast to continue, through the crest of initially more amplified large-scale mid/upper ridging across the central Great Plains into middle Mississippi/Ozark Plateau by 12Z Thursday. At the same time, downstream large-scale mid-level troughing off the southern Atlantic Seaboard appears likely to remain amplified, with some further amplification southward to the east of the Bahamas possible, with continuing cyclogenesis across the western Atlantic. Northerly flow and subsidence in the wake of this regime has contributed to considerable drying across much of the Gulf Basin into Caribbean. While some modification is ongoing across the southwestern Gulf of Mexico through northwestern Gulf coast vicinity, model forecast soundings indicate that boundary-layer moistening will remain rather modest and shallow, beneath warm and capping layers in the lower/mid-troposphere spreading east of the southern Rockies/Mexican Plateau. ...Ozark Plateau/adjacent Great Plains and Mississippi Valley... It does appear that surface low pressure will deepen to the lee of the southern Rockies, northeastward toward the southern Great Lakes region Wednesday through Wednesday night. This likely will be accompanied by strengthening southerly low-level return flow and at least some moistening. However, if, and exactly where, associated large-scale forcing for ascent and destabilization become sufficient to overcome mid-level inhibition remains unclear based on latest model output. Guidance continues to suggest that any thunderstorm development will probably be rooted within the evolving lower/mid-tropospheric warm advection regime across and east-northeast of the Ozark Plateau vicinity late Wednesday evening through early Thursday, though probabilities at any particular location appear low (on the order of 10-20 percent). It might not be out of the question that initial thunderstorm development could be accompanied by some risk for severe hail somewhere across parts of the Ozark Plateau and adjacent Great Plains/middle Mississippi Valley, but this potential stills seems rather conditional at this point. ..Kerr.. 02/20/2024 Read more