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MD 0097 CONCERNING FREEZING RAIN FOR PARTS OF SOUTHERN PENNSYLVANIA AND NORTHWEST MARYLAND
Mesoscale Discussion 0097 NWS Storm Prediction Center Norman OK 1150 AM CST Sat Feb 15 2025 Areas affected...parts of southern Pennsylvania and northwest Maryland Concerning...Freezing rain Valid 151750Z - 152145Z SUMMARY...Freezing rain is expected with ice accretion of 0.05" to 0.1" is possible this afternoon across parts of south-central Pennsylvania and adjacent areas of Maryland. DISCUSSION...A broad area of low-level warm advection across the mid-Atlantic states is providing the lift for widespread precipitation occurring across the region. The transition zone from snow across the northern parts of the region to rain across the southern parts is currently across southwestern Pennsylvania into northeastern West Virginia, which should generally lift northeastward with time. The advance of the warmer mid-level air is apparent on KCCX radar with lowered correlation coefficient indicating melting of hydrometeors. However, the surface cold air has been slow to erode, with parts of south-central Pennsylvania and adjacent areas of Maryland remaining below freezing at the surface. A couple surface sites across south-central Pennsylvania and adjacent areas of West Virginia and Maryland are reporting unknown precip with temperatures below freezing, likely indicating a transition to freezing rain has begin. NAM forecast profiles this afternoon across parts of the region show classic freezing rain conditions, with a shallow layer of below-freezing air with a large warm nose aloft. One potential mitigating factor for ice accretion is that surface wet-bulb temperatures generally hover in the 30-32 F range, which is marginal for significant ice accretion. With time, expect the low-level cold air to erode and transition to all rain later this afternoon as the precipitation ends from west to east. ..Supinie.. 02/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CTP...LWX...PBZ... LAT...LON 39907979 40427946 40617901 40827861 40917805 40837758 40607696 40177676 39837700 39677752 39617790 39597834 39587885 39607951 39727974 39907979 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CST Sat Feb 15 2025 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MISSISSIPPI VALLEY...MID SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are expected from parts of far east Texas into much of the lower Mississippi Valley and Southeast this afternoon through the overnight. Several tornadoes and scattered to numerous damaging wind gusts should be the primary threats. A few strong tornadoes are also possible. ...20Z Update... The prior outlook remains largely unchanged. The well-defined shortwave trough and 80-100 kt mid-level jet are evident on WV imagery moving across west-central TX. Rapid surface cyclogenesis is expected later this afternoon/evening as the upper trough/jet overspread a broad frontal cyclone over the eastern Red River and MS Valley vicinity. Initial semi-discrete development along the warm front is expected this afternoon with continued heating and the approach of the stronger cold front over western AR. Southwesterly flow parallel to the frontal zone and little inhibition should support quick upscale growth into a more linear mode. Strong tropospheric flow (700 mb winds of 55-75 kt) will support the potential for widespread damaging wind gusts with the line, while strong shear could also support mesovortex tornadoes. Partial clearing in the wake of earlier convection east of the frontal zone will support diurnal heating and steepening of some low and mid-level lapse rates across far eastern AR, northwestern MS and southwestern TN. The decrease in inhibition while forcing for ascent is still relatively weak may support some potential for more discrete development. While it remains unclear if this will occur, the very strong low-level shear (0-1 km BWD 40+ kt) would support a conditional significant tornado threat with any prefrontal/warm sector supercells able to evolve. ...Gulf Coast and Southeast... The strongly forced squall line is forecast to translate rapidly across much of the Southeast late this evening and overnight. Strong low-level warm air advection and broad ascent ahead of the upper trough could support isolated discrete development, and a some strong tornado potential ahead of the line, especially farther south across southern MS/AL. However, poor lapse rates aloft lend low confidence to any discrete supercells being maintained. Damaging gusts and line-embedded tornado will remain possible overnight. For more info see the prior outlook. ..Lyons.. 02/15/2025 .PREV DISCUSSION... /ISSUED 1042 AM CST Sat Feb 15 2025/ ...Synopsis... Water-vapor imagery this morning shows a potent mid-level trough over the Permian Basin pivoting east through the base of a larger scale trough forecast to shift from the Rockies east into the MS Valley. A complex surface pattern is evident with a low over OK with an accompanying trailing cold front, while a maritime boundary/residual frontal zone is draped over east TX arcing northeastward into the MS/AR/TN border region and then southeastward into the northeast Gulf of America. As the cyclone consolidates and moves eastward this afternoon into AR, the aforementioned composite boundary will advance northward as a warm front into the Mid South and towards the southern Appalachians late. The cold front is forecast to push southeast and overtake the western portion of the warm sector late today into tonight and provide a focus for numerous developing thunderstorms in the form of a squall line. ...East Texas into the Lower Mississippi Valley and Southeast... Strong low-level warm advection has resulted in scattered showers/thunderstorms mainly north of the warm front from AR east into TN. Southerly flow will promote poleward moist advection with 60s deg F dewpoints spreading north across the lower MS Valley into parts of the Mid South. The destabilizing warm sector will remain capped during the day before stronger large-scale ascent approaching from the west results in a extensive thunderstorm development from the Ark-La-Tex northeast into eastern AR/western TN/KY. Filtered daytime heating and low-level moistening will aid in the development of around 500-1000 J/kg of MLCAPE by mid to late afternoon. Surface-based thunderstorms are forecast to develop by mid afternoon near or on the cold front from east TX into the Mid South. Only a narrow window of opportunity for supercells will likely occur before rapid upscale growth into an extensive squall line by early evening. Strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily aid updraft rotation and organized severe thunderstorms. Ample low-level shear will support a threat for several line-embedded tornadoes beginning from late this afternoon through early Sunday morning. The potential for supercells ahead of the line will likely remain limited but will be greatest perhaps over the southern parts of MS/AL tonight. However, if cellular structures are maintained in the large-scale thunderstorm band, an accompanying risk for tornadoes may focus there and with any bowing inflections in the line. Given the low CAPE/high shear setup with relatively modest lapse rates and moist profiles, scattered to numerous severe/damaging winds will likely occur with the squall line as it matures. Have increased damaging wind probabilities from parts of MS into AL where confidence is greatest for damaging gusts later tonight. A continued tornado/damaging wind risk will become increasingly confined to the Gulf coastal plain late tonight into the early Sunday morning hours. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1237 PM CST Sat Feb 15 2025 Valid 171200Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Lightning potential will remain minimal across the U.S. on Monday. ...Discussion... Weakly cyclonic flow aloft will prevail across most of the U.S. Monday. At the surface, cold high pressure will continue ridging southeastward out of the Canadian Prairie, resulting in stable conditions and a general lack of thunder potential. A flash or two cannot be ruled out across portions of the West, as a short-wave trough shifts southeastward out of the Pacific Northwest into/across the Great Basin. Showers, and possibly a thunderstorm, may also occur in the vicinity of the Florida Keys as low-level flow veers to a northeasterly direction in the wake of cold-frontal passage. Overall however, expect thunder potential to remain minimal in the aforementioned areas, and nil elsewhere. ..Goss.. 02/15/2025 Read more