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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CST Wed Feb 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms still appears negligible across the U.S. for Thursday through Thursday night. ...Synopsis... Within the northern mid-latitudes, consolidating short wave perturbations of Arctic origins are forecast to dig southwest through south of the Hudson Bay vicinity through this period. It appears that this will contribute to larger-scale mid-level trough amplification across much of eastern North America, and be accompanied by a significant cold front crossing the north central Canadian/U.S. border (from the Great Plains into the upper Great Lakes) by Thursday night. As an initially more zonal belt of westerlies across the southern mid- into subtropical latitudes trends broadly cyclonic east of the Rockies into the Southeast, one embedded short wave currently emerging from the Southwest, is forecast to gradually dig from the Ozark Plateau/lower Ohio Valley vicinity through the Tennessee Valley/southern Appalachians Thursday through Thursday night. Downstream, initially amplified mid-level troughing over the southwestern Atlantic will continue to progress away from the southern Atlantic Seaboard. Upstream, models indicate that a lower/mid-tropospheric cyclone may gradually redevelop southward across the mid- into subtropical latitudes of the eastern Pacific, preceded by building mid-level ridging across California into the Great Basin. Northerly flow and subsidence in the wake of the Atlantic mid-level trough has contributed to relatively dry conditions across much of the Gulf Basin and Caribbean. Although some modification has been occurring across parts of the western Gulf of Mexico, and supporting a limited ongoing return flow of moisture across south/southeast Texas toward the Ozark Plateau vicinity, boundary-layer moistening over the western Gulf remains rather modest and shallow, beneath warm/dry layers in the lower/mid-troposphere advecting east of the Rockies/Mexican Plateau. ...Ozark Plateau into Ohio and Tennessee Valleys... Model forecast soundings generally suggest only gradual further boundary-layer moistening and deepening across the northwestern Gulf of Mexico through Thursday night, and little substantive improvement of the low-level moist return flow across the lower Mississippi into Ohio and Tennessee Valleys. Beneath warm-layers farther aloft, forecast soundings suggest that this will yield only weak CAPE where larger-scale ascent is able to overcome mid-level inhibition. And it appears that stronger forcing for ascent supportive of thunderstorm initiation may tend to remain focused above moist adiabatic to more stable near-surface lapse rates throughout the period. Scattered initial thunderstorm development across the lower Ohio Valley will probably be supported by forcing for ascent aided by low-level warm advection preceding slowly deepening surface troughing, well in advance of the Arctic front. However, various model output, including some convection allowing guidance, suggests that a weak developing cold front within this surface troughing could become a focus for an organizing line of thunderstorms across the lower Ohio through Tennessee Valleys late Thursday afternoon into Thursday night. While it might not be out of the question that some of this activity could be accompanied by small hail and gusty winds, with surface cyclogenesis and lower/mid-tropospheric wind fields forecast to remain seasonably modest to weak, the potential for severe weather still appears negligible. ..Kerr.. 02/21/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CST Wed Feb 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms still appears negligible across the U.S. for Thursday through Thursday night. ...Synopsis... Within the northern mid-latitudes, consolidating short wave perturbations of Arctic origins are forecast to dig southwest through south of the Hudson Bay vicinity through this period. It appears that this will contribute to larger-scale mid-level trough amplification across much of eastern North America, and be accompanied by a significant cold front crossing the north central Canadian/U.S. border (from the Great Plains into the upper Great Lakes) by Thursday night. As an initially more zonal belt of westerlies across the southern mid- into subtropical latitudes trends broadly cyclonic east of the Rockies into the Southeast, one embedded short wave currently emerging from the Southwest, is forecast to gradually dig from the Ozark Plateau/lower Ohio Valley vicinity through the Tennessee Valley/southern Appalachians Thursday through Thursday night. Downstream, initially amplified mid-level troughing over the southwestern Atlantic will continue to progress away from the southern Atlantic Seaboard. Upstream, models indicate that a lower/mid-tropospheric cyclone may gradually redevelop southward across the mid- into subtropical latitudes of the eastern Pacific, preceded by building mid-level ridging across California into the Great Basin. Northerly flow and subsidence in the wake of the Atlantic mid-level trough has contributed to relatively dry conditions across much of the Gulf Basin and Caribbean. Although some modification has been occurring across parts of the western Gulf of Mexico, and supporting a limited ongoing return flow of moisture across south/southeast Texas toward the Ozark Plateau vicinity, boundary-layer moistening over the western Gulf remains rather modest and shallow, beneath warm/dry layers in the lower/mid-troposphere advecting east of the Rockies/Mexican Plateau. ...Ozark Plateau into Ohio and Tennessee Valleys... Model forecast soundings generally suggest only gradual further boundary-layer moistening and deepening across the northwestern Gulf of Mexico through Thursday night, and little substantive improvement of the low-level moist return flow across the lower Mississippi into Ohio and Tennessee Valleys. Beneath warm-layers farther aloft, forecast soundings suggest that this will yield only weak CAPE where larger-scale ascent is able to overcome mid-level inhibition. And it appears that stronger forcing for ascent supportive of thunderstorm initiation may tend to remain focused above moist adiabatic to more stable near-surface lapse rates throughout the period. Scattered initial thunderstorm development across the lower Ohio Valley will probably be supported by forcing for ascent aided by low-level warm advection preceding slowly deepening surface troughing, well in advance of the Arctic front. However, various model output, including some convection allowing guidance, suggests that a weak developing cold front within this surface troughing could become a focus for an organizing line of thunderstorms across the lower Ohio through Tennessee Valleys late Thursday afternoon into Thursday night. While it might not be out of the question that some of this activity could be accompanied by small hail and gusty winds, with surface cyclogenesis and lower/mid-tropospheric wind fields forecast to remain seasonably modest to weak, the potential for severe weather still appears negligible. ..Kerr.. 02/21/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1055 AM CST Wed Feb 21 2024 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND FAR WEST TEXAS... Critical fire weather conditions are expected across southeastern New Mexico into far western Texas this afternoon, with no major changes needed to the Elevated and Critical areas this morning. Morning satellite imagery shows mainly sunny skies with temperatures warming in to the low to mid 70s and mixing already occurring in surface observations. Gusts to 45 mph are being observed in the Sacramento Mountains, with gusts generally around 20-30 mph in the lee of the higher terrain. As daytime heating continues, expect wind speeds to increase amid deeper mixing, with potential for dangerous fire weather conditions through the afternoon. See previous discussion below for more information. ..Thornton.. 02/21/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Wed Feb 21 2024/ ...Synopsis... Elevated to critical fire weather conditions are expected today across the southern High Plains. Early-morning water-vapor imagery depicts a shortwave trough off the southern CA coast gradually traversing eastward. This feature is expected to gradually de-amplify through the day, resulting in acceleration of the wave as it approaches the southern Plains. 00 UTC soundings sampled an unseasonably warm and dry air mass across the southern High Plains, with a low-level thermal trough noted in recent analyses extending from southwest TX to southwest KS. This thermal ridge is hindering overnight RH recovery with RH values in the low to mid teens noted in 06 UTC surface observations across east NM and southwest TX. Heading into this afternoon, strengthening zonal flow over the southern Rockies associated with the approach of the upper wave and attendant jet max will promote continued downslope warming/drying. Scattered high-level cirrus may filter insolation to some degree, but diurnal warming coupled with deep boundary-layer mixing and the persistent downslope flow regime will support another day of RH values in the 5-10% range. Although a slight dry bias is noted in recent runs of the RAP/HRRR, the aforementioned observed trends and RH minimums observed yesterday lend credence to this RH forecast. 20-30 mph west/southwesterly gradient winds are expected based on strong consensus between high-res ensemble members, as a surface low deepens over southwest KS and a trailing surface trough/dryline pushes east. The onset of these winds is expected to occur as soon as a shallow nocturnal inversion is mixed out, which appears most likely around 18 UTC. Favorable phasing of the mid-level jet max with peak diurnal heating/boundary-layer mixing will foster efficient downward momentum transfer, manifesting as frequent 40-50 mph gusts by late afternoon. Consequently, widespread elevated to critical fire weather conditions are expected by early afternoon across a large swath of the southern High Plains. The primary limiting factor for a more robust fire weather threat continues to be fuel status. Although some fine-fuel drying did occur yesterday/Monday, most fuels across the TX/OK Panhandles and parts of southeast CO remain only modestly receptive with ERCs near the 50th percentile. As such, the Critical risk area remains confined to far west TX to southeast NM where fuels are drier and active burning was noted on ongoing fires this afternoon in GOES IR imagery. ...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 1055 AM CST Wed Feb 21 2024 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND FAR WEST TEXAS... Critical fire weather conditions are expected across southeastern New Mexico into far western Texas this afternoon, with no major changes needed to the Elevated and Critical areas this morning. Morning satellite imagery shows mainly sunny skies with temperatures warming in to the low to mid 70s and mixing already occurring in surface observations. Gusts to 45 mph are being observed in the Sacramento Mountains, with gusts generally around 20-30 mph in the lee of the higher terrain. As daytime heating continues, expect wind speeds to increase amid deeper mixing, with potential for dangerous fire weather conditions through the afternoon. See previous discussion below for more information. ..Thornton.. 02/21/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Wed Feb 21 2024/ ...Synopsis... Elevated to critical fire weather conditions are expected today across the southern High Plains. Early-morning water-vapor imagery depicts a shortwave trough off the southern CA coast gradually traversing eastward. This feature is expected to gradually de-amplify through the day, resulting in acceleration of the wave as it approaches the southern Plains. 00 UTC soundings sampled an unseasonably warm and dry air mass across the southern High Plains, with a low-level thermal trough noted in recent analyses extending from southwest TX to southwest KS. This thermal ridge is hindering overnight RH recovery with RH values in the low to mid teens noted in 06 UTC surface observations across east NM and southwest TX. Heading into this afternoon, strengthening zonal flow over the southern Rockies associated with the approach of the upper wave and attendant jet max will promote continued downslope warming/drying. Scattered high-level cirrus may filter insolation to some degree, but diurnal warming coupled with deep boundary-layer mixing and the persistent downslope flow regime will support another day of RH values in the 5-10% range. Although a slight dry bias is noted in recent runs of the RAP/HRRR, the aforementioned observed trends and RH minimums observed yesterday lend credence to this RH forecast. 20-30 mph west/southwesterly gradient winds are expected based on strong consensus between high-res ensemble members, as a surface low deepens over southwest KS and a trailing surface trough/dryline pushes east. The onset of these winds is expected to occur as soon as a shallow nocturnal inversion is mixed out, which appears most likely around 18 UTC. Favorable phasing of the mid-level jet max with peak diurnal heating/boundary-layer mixing will foster efficient downward momentum transfer, manifesting as frequent 40-50 mph gusts by late afternoon. Consequently, widespread elevated to critical fire weather conditions are expected by early afternoon across a large swath of the southern High Plains. The primary limiting factor for a more robust fire weather threat continues to be fuel status. Although some fine-fuel drying did occur yesterday/Monday, most fuels across the TX/OK Panhandles and parts of southeast CO remain only modestly receptive with ERCs near the 50th percentile. As such, the Critical risk area remains confined to far west TX to southeast NM where fuels are drier and active burning was noted on ongoing fires this afternoon in GOES IR imagery. ...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 1055 AM CST Wed Feb 21 2024 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND FAR WEST TEXAS... Critical fire weather conditions are expected across southeastern New Mexico into far western Texas this afternoon, with no major changes needed to the Elevated and Critical areas this morning. Morning satellite imagery shows mainly sunny skies with temperatures warming in to the low to mid 70s and mixing already occurring in surface observations. Gusts to 45 mph are being observed in the Sacramento Mountains, with gusts generally around 20-30 mph in the lee of the higher terrain. As daytime heating continues, expect wind speeds to increase amid deeper mixing, with potential for dangerous fire weather conditions through the afternoon. See previous discussion below for more information. ..Thornton.. 02/21/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Wed Feb 21 2024/ ...Synopsis... Elevated to critical fire weather conditions are expected today across the southern High Plains. Early-morning water-vapor imagery depicts a shortwave trough off the southern CA coast gradually traversing eastward. This feature is expected to gradually de-amplify through the day, resulting in acceleration of the wave as it approaches the southern Plains. 00 UTC soundings sampled an unseasonably warm and dry air mass across the southern High Plains, with a low-level thermal trough noted in recent analyses extending from southwest TX to southwest KS. This thermal ridge is hindering overnight RH recovery with RH values in the low to mid teens noted in 06 UTC surface observations across east NM and southwest TX. Heading into this afternoon, strengthening zonal flow over the southern Rockies associated with the approach of the upper wave and attendant jet max will promote continued downslope warming/drying. Scattered high-level cirrus may filter insolation to some degree, but diurnal warming coupled with deep boundary-layer mixing and the persistent downslope flow regime will support another day of RH values in the 5-10% range. Although a slight dry bias is noted in recent runs of the RAP/HRRR, the aforementioned observed trends and RH minimums observed yesterday lend credence to this RH forecast. 20-30 mph west/southwesterly gradient winds are expected based on strong consensus between high-res ensemble members, as a surface low deepens over southwest KS and a trailing surface trough/dryline pushes east. The onset of these winds is expected to occur as soon as a shallow nocturnal inversion is mixed out, which appears most likely around 18 UTC. Favorable phasing of the mid-level jet max with peak diurnal heating/boundary-layer mixing will foster efficient downward momentum transfer, manifesting as frequent 40-50 mph gusts by late afternoon. Consequently, widespread elevated to critical fire weather conditions are expected by early afternoon across a large swath of the southern High Plains. The primary limiting factor for a more robust fire weather threat continues to be fuel status. Although some fine-fuel drying did occur yesterday/Monday, most fuels across the TX/OK Panhandles and parts of southeast CO remain only modestly receptive with ERCs near the 50th percentile. As such, the Critical risk area remains confined to far west TX to southeast NM where fuels are drier and active burning was noted on ongoing fires this afternoon in GOES IR imagery. ...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 1055 AM CST Wed Feb 21 2024 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND FAR WEST TEXAS... Critical fire weather conditions are expected across southeastern New Mexico into far western Texas this afternoon, with no major changes needed to the Elevated and Critical areas this morning. Morning satellite imagery shows mainly sunny skies with temperatures warming in to the low to mid 70s and mixing already occurring in surface observations. Gusts to 45 mph are being observed in the Sacramento Mountains, with gusts generally around 20-30 mph in the lee of the higher terrain. As daytime heating continues, expect wind speeds to increase amid deeper mixing, with potential for dangerous fire weather conditions through the afternoon. See previous discussion below for more information. ..Thornton.. 02/21/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Wed Feb 21 2024/ ...Synopsis... Elevated to critical fire weather conditions are expected today across the southern High Plains. Early-morning water-vapor imagery depicts a shortwave trough off the southern CA coast gradually traversing eastward. This feature is expected to gradually de-amplify through the day, resulting in acceleration of the wave as it approaches the southern Plains. 00 UTC soundings sampled an unseasonably warm and dry air mass across the southern High Plains, with a low-level thermal trough noted in recent analyses extending from southwest TX to southwest KS. This thermal ridge is hindering overnight RH recovery with RH values in the low to mid teens noted in 06 UTC surface observations across east NM and southwest TX. Heading into this afternoon, strengthening zonal flow over the southern Rockies associated with the approach of the upper wave and attendant jet max will promote continued downslope warming/drying. Scattered high-level cirrus may filter insolation to some degree, but diurnal warming coupled with deep boundary-layer mixing and the persistent downslope flow regime will support another day of RH values in the 5-10% range. Although a slight dry bias is noted in recent runs of the RAP/HRRR, the aforementioned observed trends and RH minimums observed yesterday lend credence to this RH forecast. 20-30 mph west/southwesterly gradient winds are expected based on strong consensus between high-res ensemble members, as a surface low deepens over southwest KS and a trailing surface trough/dryline pushes east. The onset of these winds is expected to occur as soon as a shallow nocturnal inversion is mixed out, which appears most likely around 18 UTC. Favorable phasing of the mid-level jet max with peak diurnal heating/boundary-layer mixing will foster efficient downward momentum transfer, manifesting as frequent 40-50 mph gusts by late afternoon. Consequently, widespread elevated to critical fire weather conditions are expected by early afternoon across a large swath of the southern High Plains. The primary limiting factor for a more robust fire weather threat continues to be fuel status. Although some fine-fuel drying did occur yesterday/Monday, most fuels across the TX/OK Panhandles and parts of southeast CO remain only modestly receptive with ERCs near the 50th percentile. As such, the Critical risk area remains confined to far west TX to southeast NM where fuels are drier and active burning was noted on ongoing fires this afternoon in GOES IR imagery. ...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 1055 AM CST Wed Feb 21 2024 Valid 211700Z - 221200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHEASTERN NEW MEXICO AND FAR WEST TEXAS... Critical fire weather conditions are expected across southeastern New Mexico into far western Texas this afternoon, with no major changes needed to the Elevated and Critical areas this morning. Morning satellite imagery shows mainly sunny skies with temperatures warming in to the low to mid 70s and mixing already occurring in surface observations. Gusts to 45 mph are being observed in the Sacramento Mountains, with gusts generally around 20-30 mph in the lee of the higher terrain. As daytime heating continues, expect wind speeds to increase amid deeper mixing, with potential for dangerous fire weather conditions through the afternoon. See previous discussion below for more information. ..Thornton.. 02/21/2024 .PREV DISCUSSION... /ISSUED 0100 AM CST Wed Feb 21 2024/ ...Synopsis... Elevated to critical fire weather conditions are expected today across the southern High Plains. Early-morning water-vapor imagery depicts a shortwave trough off the southern CA coast gradually traversing eastward. This feature is expected to gradually de-amplify through the day, resulting in acceleration of the wave as it approaches the southern Plains. 00 UTC soundings sampled an unseasonably warm and dry air mass across the southern High Plains, with a low-level thermal trough noted in recent analyses extending from southwest TX to southwest KS. This thermal ridge is hindering overnight RH recovery with RH values in the low to mid teens noted in 06 UTC surface observations across east NM and southwest TX. Heading into this afternoon, strengthening zonal flow over the southern Rockies associated with the approach of the upper wave and attendant jet max will promote continued downslope warming/drying. Scattered high-level cirrus may filter insolation to some degree, but diurnal warming coupled with deep boundary-layer mixing and the persistent downslope flow regime will support another day of RH values in the 5-10% range. Although a slight dry bias is noted in recent runs of the RAP/HRRR, the aforementioned observed trends and RH minimums observed yesterday lend credence to this RH forecast. 20-30 mph west/southwesterly gradient winds are expected based on strong consensus between high-res ensemble members, as a surface low deepens over southwest KS and a trailing surface trough/dryline pushes east. The onset of these winds is expected to occur as soon as a shallow nocturnal inversion is mixed out, which appears most likely around 18 UTC. Favorable phasing of the mid-level jet max with peak diurnal heating/boundary-layer mixing will foster efficient downward momentum transfer, manifesting as frequent 40-50 mph gusts by late afternoon. Consequently, widespread elevated to critical fire weather conditions are expected by early afternoon across a large swath of the southern High Plains. The primary limiting factor for a more robust fire weather threat continues to be fuel status. Although some fine-fuel drying did occur yesterday/Monday, most fuels across the TX/OK Panhandles and parts of southeast CO remain only modestly receptive with ERCs near the 50th percentile. As such, the Critical risk area remains confined to far west TX to southeast NM where fuels are drier and active burning was noted on ongoing fires this afternoon in GOES IR imagery. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Feb 21 2024 Valid 211630Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS OF THE MID MISSISSIPPI VALLEY... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Southern MO... Morning water vapor loop shows a fast-moving shortwave trough over southern CA. This feature and its associated mid-level jet max will track across the southern Plains and into the mid MS valley by late tonight. Ahead of this system, strengthening southwesterly low-level winds will enhance warm/moist advection into parts of MO/IL, leading to a zone of modest instability after dark from southeast KS across much of southern MO. Forecast soundings from several 12z models indicate the boundary-layer remains capped, suggesting the prospects for robust thunderstorm development are rather low. However, a few morning CAM solutions do show a storm or two overnight, which given the steep mid-level lapse rates and strong shear would be capable of hail. Therefore, will maintain the ongoing MRGL risk area to denote the conditional risk. ...Northern IL/IN... A surface warm front is expected to become established from central MO into central IL later today. Low-level winds are expected to be rather weak in vicinity of the boundary, but flow into the mid-levels should result in elevated warm-advection and the initiation of a few thunderstorms after midnight. Forecast soundings suggest the potential for hail in the strongest cells, although the potential for severe-caliber hail appears marginal. ..Hart/Squitieri.. 02/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Feb 21 2024 Valid 211630Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS OF THE MID MISSISSIPPI VALLEY... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Southern MO... Morning water vapor loop shows a fast-moving shortwave trough over southern CA. This feature and its associated mid-level jet max will track across the southern Plains and into the mid MS valley by late tonight. Ahead of this system, strengthening southwesterly low-level winds will enhance warm/moist advection into parts of MO/IL, leading to a zone of modest instability after dark from southeast KS across much of southern MO. Forecast soundings from several 12z models indicate the boundary-layer remains capped, suggesting the prospects for robust thunderstorm development are rather low. However, a few morning CAM solutions do show a storm or two overnight, which given the steep mid-level lapse rates and strong shear would be capable of hail. Therefore, will maintain the ongoing MRGL risk area to denote the conditional risk. ...Northern IL/IN... A surface warm front is expected to become established from central MO into central IL later today. Low-level winds are expected to be rather weak in vicinity of the boundary, but flow into the mid-levels should result in elevated warm-advection and the initiation of a few thunderstorms after midnight. Forecast soundings suggest the potential for hail in the strongest cells, although the potential for severe-caliber hail appears marginal. ..Hart/Squitieri.. 02/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Feb 21 2024 Valid 211630Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS OF THE MID MISSISSIPPI VALLEY... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Southern MO... Morning water vapor loop shows a fast-moving shortwave trough over southern CA. This feature and its associated mid-level jet max will track across the southern Plains and into the mid MS valley by late tonight. Ahead of this system, strengthening southwesterly low-level winds will enhance warm/moist advection into parts of MO/IL, leading to a zone of modest instability after dark from southeast KS across much of southern MO. Forecast soundings from several 12z models indicate the boundary-layer remains capped, suggesting the prospects for robust thunderstorm development are rather low. However, a few morning CAM solutions do show a storm or two overnight, which given the steep mid-level lapse rates and strong shear would be capable of hail. Therefore, will maintain the ongoing MRGL risk area to denote the conditional risk. ...Northern IL/IN... A surface warm front is expected to become established from central MO into central IL later today. Low-level winds are expected to be rather weak in vicinity of the boundary, but flow into the mid-levels should result in elevated warm-advection and the initiation of a few thunderstorms after midnight. Forecast soundings suggest the potential for hail in the strongest cells, although the potential for severe-caliber hail appears marginal. ..Hart/Squitieri.. 02/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Feb 21 2024 Valid 211630Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS OF THE MID MISSISSIPPI VALLEY... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Southern MO... Morning water vapor loop shows a fast-moving shortwave trough over southern CA. This feature and its associated mid-level jet max will track across the southern Plains and into the mid MS valley by late tonight. Ahead of this system, strengthening southwesterly low-level winds will enhance warm/moist advection into parts of MO/IL, leading to a zone of modest instability after dark from southeast KS across much of southern MO. Forecast soundings from several 12z models indicate the boundary-layer remains capped, suggesting the prospects for robust thunderstorm development are rather low. However, a few morning CAM solutions do show a storm or two overnight, which given the steep mid-level lapse rates and strong shear would be capable of hail. Therefore, will maintain the ongoing MRGL risk area to denote the conditional risk. ...Northern IL/IN... A surface warm front is expected to become established from central MO into central IL later today. Low-level winds are expected to be rather weak in vicinity of the boundary, but flow into the mid-levels should result in elevated warm-advection and the initiation of a few thunderstorms after midnight. Forecast soundings suggest the potential for hail in the strongest cells, although the potential for severe-caliber hail appears marginal. ..Hart/Squitieri.. 02/21/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Feb 21 2024 Valid 211630Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT OVER PORTIONS OF THE MID MISSISSIPPI VALLEY... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Southern MO... Morning water vapor loop shows a fast-moving shortwave trough over southern CA. This feature and its associated mid-level jet max will track across the southern Plains and into the mid MS valley by late tonight. Ahead of this system, strengthening southwesterly low-level winds will enhance warm/moist advection into parts of MO/IL, leading to a zone of modest instability after dark from southeast KS across much of southern MO. Forecast soundings from several 12z models indicate the boundary-layer remains capped, suggesting the prospects for robust thunderstorm development are rather low. However, a few morning CAM solutions do show a storm or two overnight, which given the steep mid-level lapse rates and strong shear would be capable of hail. Therefore, will maintain the ongoing MRGL risk area to denote the conditional risk. ...Northern IL/IN... A surface warm front is expected to become established from central MO into central IL later today. Low-level winds are expected to be rather weak in vicinity of the boundary, but flow into the mid-levels should result in elevated warm-advection and the initiation of a few thunderstorms after midnight. Forecast soundings suggest the potential for hail in the strongest cells, although the potential for severe-caliber hail appears marginal. ..Hart/Squitieri.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Wed Feb 21 2024 Valid 211300Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE WESTERN OZARKS REGION AND OVER NORTH-CENTRAL PARTS OF ILLINOIS AND INDIANA... ...SUMMARY... Areas of strong thunderstorm development are possible across parts of the Ozark Plateau and adjacent Great Plains and across central Illinois to far western Indiana late Wednesday evening into early Thursday, with some risk for severe hail. ...Synopsis... The mid/upper-level pattern will trend more toward zonal through the period, as a well-developed southern-stream shortwave trough now near coastal southern CA moves quickly east-northeastward and penetrates a low-amplitude mean ridge over the central CONUS. This perturbation should cross the central/southern High Plains around 00Z, then deamplify somewhat as its northern part enters confluent flow and height falls ahead of a northern-stream trough crossing the Upper Midwest. By 12Z, the southern perturbation should reach from northern parts of IL/IN to southwestern MO and northwestern AR. At the surface, 11Z analysis depicted a wavy, slow-moving frontal zone from northernmost Lower MI across southern WI, through a weak low near DBQ, to near MKC, EMP and through a broad area of low pressure over western KS. Cyclogenesis is forecast today over the western KS region, shifting eastward across KS to near MKC by 06Z, trailing a cold front southwestward over northern OK. The Great Lakes/Mississippi Valley frontal segment should move southeastward then stall. A secondary low is possible along the cold front over northern OK by 06Z, when a warm to stationary front should extend from the MKC-area low across central parts of IL/IN. ...Ozarks to southern Great Lakes region... Isolated to scattered, elevated thunderstorms are expected to develop across portions of IL/IN and perhaps the western Ozarks region overnight, shifting/expanding eastward especially across the IL/IN region. Activity will attain greatest coverage after 06Z, and may pose a risk of marginally severe hail. Low-level warm/moist advection above the boundary layer is underway in a relatively dry, early-stage return-flow event across a broad corridor from the southern Plains to the Ohio Valley and southern Great Lakes States. The warm-advection plume should become more confluent and moist through today, and especially this evening into tonight, as it intensifies with the approach of the southern shortwave trough. Though the return-flow regime still will be far from mature or optimal, moist advection/transport will persist such that increasingly high-theta-e parcels are involved, and ultimately lifted to an LFC. The two areas with the most such progged lift are in and near the "marginal risk" outlooks. The northern area should have greater lift and thunderstorm coverage thanks to contribution from elevated, low-level frontal forcing, while theta-e and midlevel lapse rates will be greater above a relatively stable boundary layer in the southern area. Albeit with much-different vertical distributions, both areas should attain around 500-1200 J/kg MUCAPE, with greater effective shear in the northern area (35-45 kt), and a stronger proximate LLJ (45-55 kt) for the southern area across the Ozarks. However, despite a favorable environment for severe hail, given thunderstorms, the southern region appears more conditional because of stronger CINH, imparted by the same EML that is providing the high lapse rate. That implies less convective coverage, and some (not all) convection-allowing progs with weaker indicators of isentropic ascent indicate none -- despite greater moisture content in the potential inflow region. ..Edwards/Mosier.. 02/21/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CST Wed Feb 21 2024 Valid 241200Z - 291200Z ...DISCUSSION... The upper-air pattern will be hostile to severe-thunderstorm development through at least Sunday with gradually increasing potential for thunderstorms by Monday over the central U.S. Of particular interest will be the Tuesday-Wednesday timeframe, as models continue to indicate a powerful mid-level trough over the West ejecting into the central U.S. on Tuesday and into the OH Valley/South on Wednesday. Model run-to-run variability remains large but a couple of days of northward moisture return into the southern Great Plains/MS Valley will conditionally favor potential for severe thunderstorms. If additional model runs exhibit consistency in the timing and general placement of the ejecting trough over the next day, this will likely prompt consideration for a severe-weather spatial highlight on Tuesday from the northeast TX-OK vicinity northeastward into the lower MO Valley. Additional severe potential may extend from the lower MS Valley/South northward into the Mid South and potentially OH Valley on Wednesday. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0319 AM CST Wed Feb 21 2024 Valid 241200Z - 291200Z ...DISCUSSION... The upper-air pattern will be hostile to severe-thunderstorm development through at least Sunday with gradually increasing potential for thunderstorms by Monday over the central U.S. Of particular interest will be the Tuesday-Wednesday timeframe, as models continue to indicate a powerful mid-level trough over the West ejecting into the central U.S. on Tuesday and into the OH Valley/South on Wednesday. Model run-to-run variability remains large but a couple of days of northward moisture return into the southern Great Plains/MS Valley will conditionally favor potential for severe thunderstorms. If additional model runs exhibit consistency in the timing and general placement of the ejecting trough over the next day, this will likely prompt consideration for a severe-weather spatial highlight on Tuesday from the northeast TX-OK vicinity northeastward into the lower MO Valley. Additional severe potential may extend from the lower MS Valley/South northward into the Mid South and potentially OH Valley on Wednesday. Read more