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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

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

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

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Feb 21 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad, large-scale mid-level trough located to the east of the Rockies on Friday morning, will feature a speed max moving through its base over the Southeast. A surface low in the Mid-Atlantic states will move east and offshore into the western Atlantic during the day, as a cold front continues southeast into the Carolina shelf waters by mid afternoon and into the FL Peninsula. South-southwesterly low-level flow will aid in moist advection ahead of the front, but 50s to low 60s deg F dewpoints over the Carolinas into north FL are currently forecast. Isolated to scattered showers/thunderstorms and associated cloud cover during the morning will likely delay/inhibit stronger heating from occurring prior to frontal passage over much of the Carolina Piedmont. The exception may be over the immediate coastal areas of SC/GA and the FL Peninsula where a low chance for diurnal storm development could occur. Given the uncertainty with weak destabilization and the potential for timing/placement errors of possible low-topped convection, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/21/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Feb 21 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad, large-scale mid-level trough located to the east of the Rockies on Friday morning, will feature a speed max moving through its base over the Southeast. A surface low in the Mid-Atlantic states will move east and offshore into the western Atlantic during the day, as a cold front continues southeast into the Carolina shelf waters by mid afternoon and into the FL Peninsula. South-southwesterly low-level flow will aid in moist advection ahead of the front, but 50s to low 60s deg F dewpoints over the Carolinas into north FL are currently forecast. Isolated to scattered showers/thunderstorms and associated cloud cover during the morning will likely delay/inhibit stronger heating from occurring prior to frontal passage over much of the Carolina Piedmont. The exception may be over the immediate coastal areas of SC/GA and the FL Peninsula where a low chance for diurnal storm development could occur. Given the uncertainty with weak destabilization and the potential for timing/placement errors of possible low-topped convection, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/21/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Feb 21 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad, large-scale mid-level trough located to the east of the Rockies on Friday morning, will feature a speed max moving through its base over the Southeast. A surface low in the Mid-Atlantic states will move east and offshore into the western Atlantic during the day, as a cold front continues southeast into the Carolina shelf waters by mid afternoon and into the FL Peninsula. South-southwesterly low-level flow will aid in moist advection ahead of the front, but 50s to low 60s deg F dewpoints over the Carolinas into north FL are currently forecast. Isolated to scattered showers/thunderstorms and associated cloud cover during the morning will likely delay/inhibit stronger heating from occurring prior to frontal passage over much of the Carolina Piedmont. The exception may be over the immediate coastal areas of SC/GA and the FL Peninsula where a low chance for diurnal storm development could occur. Given the uncertainty with weak destabilization and the potential for timing/placement errors of possible low-topped convection, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/21/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Feb 21 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad, large-scale mid-level trough located to the east of the Rockies on Friday morning, will feature a speed max moving through its base over the Southeast. A surface low in the Mid-Atlantic states will move east and offshore into the western Atlantic during the day, as a cold front continues southeast into the Carolina shelf waters by mid afternoon and into the FL Peninsula. South-southwesterly low-level flow will aid in moist advection ahead of the front, but 50s to low 60s deg F dewpoints over the Carolinas into north FL are currently forecast. Isolated to scattered showers/thunderstorms and associated cloud cover during the morning will likely delay/inhibit stronger heating from occurring prior to frontal passage over much of the Carolina Piedmont. The exception may be over the immediate coastal areas of SC/GA and the FL Peninsula where a low chance for diurnal storm development could occur. Given the uncertainty with weak destabilization and the potential for timing/placement errors of possible low-topped convection, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/21/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CST Wed Feb 21 2024 Valid 231200Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast across the contiguous United States on Friday. ...Synopsis... A broad, large-scale mid-level trough located to the east of the Rockies on Friday morning, will feature a speed max moving through its base over the Southeast. A surface low in the Mid-Atlantic states will move east and offshore into the western Atlantic during the day, as a cold front continues southeast into the Carolina shelf waters by mid afternoon and into the FL Peninsula. South-southwesterly low-level flow will aid in moist advection ahead of the front, but 50s to low 60s deg F dewpoints over the Carolinas into north FL are currently forecast. Isolated to scattered showers/thunderstorms and associated cloud cover during the morning will likely delay/inhibit stronger heating from occurring prior to frontal passage over much of the Carolina Piedmont. The exception may be over the immediate coastal areas of SC/GA and the FL Peninsula where a low chance for diurnal storm development could occur. Given the uncertainty with weak destabilization and the potential for timing/placement errors of possible low-topped convection, will defer the possible inclusion of low-severe probabilities to later outlooks. Elsewhere, cool and/or dry and stable conditions will occur over much of the rest of the Lower 48 states. ..Smith.. 02/21/2024 Read more