Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1258 PM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The Elevated area has been expanded into parts of central/southern Missouri. Updated fuel information has increased confidence in potential for fire spread. Winds of around 20 mph do appear probable, though RH may only be marginally reduced. The timing of the front should allow for a few hours of these conditions during the afternoon. With regard to potential for sustained critical conditions, western Oklahoma is the most probable per latest ensemble guidance. However, duration is still uncertain enough to withhold Critical highlights. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0204 AM CST Mon Feb 26 2024/ ...Synopsis... Across the western US, an amplifying Pacific trough will begin to phase with intensifying southern stream flow as it crosses the southern and central Rockies into the Plains. A strong lee low will move over the central Plains with dry and breezy conditions likely behind a trailing dryline/surface pressure trough. Favorable meteorological conditions and at least somewhat receptive fuels should support widespread elevated to near-critical fire-weather concerns over parts of the southern Plains. ...southern Plains... As the aforementioned trough begins to move over the Plains early D2/Tuesday, strong low-level flow is expected to develop by mid morning. Westerly winds of 20-25 mph, with gusts of 30-35 mph, are possible across parts of western and central OK and the TX Panhandle. Despite dry downsloping and the unusually warm temperatures, increasing mid and high-level cloud cover may limit diurnal RH minimums to near 20-25%. Pre-greenup fuels have shown some drying over the previous days, but remain only partially receptive to broader fire spread despite the favorable meteorological conditions. Still, widespread elevated to near/briefly critical fire-weather conditions appear likely. The greatest confidence in potentially longer-lived critical conditions is across parts of western and central OK and the eastern TX Panhandle where the strongest winds are expected to overlap more receptive fuels for the greatest duration. Fire-weather concerns will begin to diminish later in the evening as a cold front rapidly moves south. Strong gusts may persist behind the front along with a rapid wind shift to north/northwesterly. Cooler temperatures and higher RH behind the front should quickly limit sustained fire-weather concerns through the overnight hours. ...Midwest... Farther to the northeast, gusty southwest winds and very warm/dry conditions are expected southwest of the advancing low across parts of MO and western IL. A pronounced low-level thermal ridge overlaying southwest winds of 20-30 mph may support brief elevated or locally critical fire-weather conditions Tuesday afternoon. Area fuels have shown increased dryness over the past several days, but remain partially receptive to fire spread. Thus, confidence in sustained fire-weather conditions is low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1258 PM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The Elevated area has been expanded into parts of central/southern Missouri. Updated fuel information has increased confidence in potential for fire spread. Winds of around 20 mph do appear probable, though RH may only be marginally reduced. The timing of the front should allow for a few hours of these conditions during the afternoon. With regard to potential for sustained critical conditions, western Oklahoma is the most probable per latest ensemble guidance. However, duration is still uncertain enough to withhold Critical highlights. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0204 AM CST Mon Feb 26 2024/ ...Synopsis... Across the western US, an amplifying Pacific trough will begin to phase with intensifying southern stream flow as it crosses the southern and central Rockies into the Plains. A strong lee low will move over the central Plains with dry and breezy conditions likely behind a trailing dryline/surface pressure trough. Favorable meteorological conditions and at least somewhat receptive fuels should support widespread elevated to near-critical fire-weather concerns over parts of the southern Plains. ...southern Plains... As the aforementioned trough begins to move over the Plains early D2/Tuesday, strong low-level flow is expected to develop by mid morning. Westerly winds of 20-25 mph, with gusts of 30-35 mph, are possible across parts of western and central OK and the TX Panhandle. Despite dry downsloping and the unusually warm temperatures, increasing mid and high-level cloud cover may limit diurnal RH minimums to near 20-25%. Pre-greenup fuels have shown some drying over the previous days, but remain only partially receptive to broader fire spread despite the favorable meteorological conditions. Still, widespread elevated to near/briefly critical fire-weather conditions appear likely. The greatest confidence in potentially longer-lived critical conditions is across parts of western and central OK and the eastern TX Panhandle where the strongest winds are expected to overlap more receptive fuels for the greatest duration. Fire-weather concerns will begin to diminish later in the evening as a cold front rapidly moves south. Strong gusts may persist behind the front along with a rapid wind shift to north/northwesterly. Cooler temperatures and higher RH behind the front should quickly limit sustained fire-weather concerns through the overnight hours. ...Midwest... Farther to the northeast, gusty southwest winds and very warm/dry conditions are expected southwest of the advancing low across parts of MO and western IL. A pronounced low-level thermal ridge overlaying southwest winds of 20-30 mph may support brief elevated or locally critical fire-weather conditions Tuesday afternoon. Area fuels have shown increased dryness over the past several days, but remain partially receptive to fire spread. Thus, confidence in sustained fire-weather conditions is low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1258 PM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The Elevated area has been expanded into parts of central/southern Missouri. Updated fuel information has increased confidence in potential for fire spread. Winds of around 20 mph do appear probable, though RH may only be marginally reduced. The timing of the front should allow for a few hours of these conditions during the afternoon. With regard to potential for sustained critical conditions, western Oklahoma is the most probable per latest ensemble guidance. However, duration is still uncertain enough to withhold Critical highlights. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0204 AM CST Mon Feb 26 2024/ ...Synopsis... Across the western US, an amplifying Pacific trough will begin to phase with intensifying southern stream flow as it crosses the southern and central Rockies into the Plains. A strong lee low will move over the central Plains with dry and breezy conditions likely behind a trailing dryline/surface pressure trough. Favorable meteorological conditions and at least somewhat receptive fuels should support widespread elevated to near-critical fire-weather concerns over parts of the southern Plains. ...southern Plains... As the aforementioned trough begins to move over the Plains early D2/Tuesday, strong low-level flow is expected to develop by mid morning. Westerly winds of 20-25 mph, with gusts of 30-35 mph, are possible across parts of western and central OK and the TX Panhandle. Despite dry downsloping and the unusually warm temperatures, increasing mid and high-level cloud cover may limit diurnal RH minimums to near 20-25%. Pre-greenup fuels have shown some drying over the previous days, but remain only partially receptive to broader fire spread despite the favorable meteorological conditions. Still, widespread elevated to near/briefly critical fire-weather conditions appear likely. The greatest confidence in potentially longer-lived critical conditions is across parts of western and central OK and the eastern TX Panhandle where the strongest winds are expected to overlap more receptive fuels for the greatest duration. Fire-weather concerns will begin to diminish later in the evening as a cold front rapidly moves south. Strong gusts may persist behind the front along with a rapid wind shift to north/northwesterly. Cooler temperatures and higher RH behind the front should quickly limit sustained fire-weather concerns through the overnight hours. ...Midwest... Farther to the northeast, gusty southwest winds and very warm/dry conditions are expected southwest of the advancing low across parts of MO and western IL. A pronounced low-level thermal ridge overlaying southwest winds of 20-30 mph may support brief elevated or locally critical fire-weather conditions Tuesday afternoon. Area fuels have shown increased dryness over the past several days, but remain partially receptive to fire spread. Thus, confidence in sustained fire-weather conditions is low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1258 PM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The Elevated area has been expanded into parts of central/southern Missouri. Updated fuel information has increased confidence in potential for fire spread. Winds of around 20 mph do appear probable, though RH may only be marginally reduced. The timing of the front should allow for a few hours of these conditions during the afternoon. With regard to potential for sustained critical conditions, western Oklahoma is the most probable per latest ensemble guidance. However, duration is still uncertain enough to withhold Critical highlights. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0204 AM CST Mon Feb 26 2024/ ...Synopsis... Across the western US, an amplifying Pacific trough will begin to phase with intensifying southern stream flow as it crosses the southern and central Rockies into the Plains. A strong lee low will move over the central Plains with dry and breezy conditions likely behind a trailing dryline/surface pressure trough. Favorable meteorological conditions and at least somewhat receptive fuels should support widespread elevated to near-critical fire-weather concerns over parts of the southern Plains. ...southern Plains... As the aforementioned trough begins to move over the Plains early D2/Tuesday, strong low-level flow is expected to develop by mid morning. Westerly winds of 20-25 mph, with gusts of 30-35 mph, are possible across parts of western and central OK and the TX Panhandle. Despite dry downsloping and the unusually warm temperatures, increasing mid and high-level cloud cover may limit diurnal RH minimums to near 20-25%. Pre-greenup fuels have shown some drying over the previous days, but remain only partially receptive to broader fire spread despite the favorable meteorological conditions. Still, widespread elevated to near/briefly critical fire-weather conditions appear likely. The greatest confidence in potentially longer-lived critical conditions is across parts of western and central OK and the eastern TX Panhandle where the strongest winds are expected to overlap more receptive fuels for the greatest duration. Fire-weather concerns will begin to diminish later in the evening as a cold front rapidly moves south. Strong gusts may persist behind the front along with a rapid wind shift to north/northwesterly. Cooler temperatures and higher RH behind the front should quickly limit sustained fire-weather concerns through the overnight hours. ...Midwest... Farther to the northeast, gusty southwest winds and very warm/dry conditions are expected southwest of the advancing low across parts of MO and western IL. A pronounced low-level thermal ridge overlaying southwest winds of 20-30 mph may support brief elevated or locally critical fire-weather conditions Tuesday afternoon. Area fuels have shown increased dryness over the past several days, but remain partially receptive to fire spread. Thus, confidence in sustained fire-weather conditions is low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CST Mon Feb 26 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL MISSOURI INTO ILLINOIS...INDIANA...NORTHWEST OHIO...AND SOUTHERN LOWER MICHIGAN... ...SUMMARY... Scattered strong to severe thunderstorms, associated with large hail (some near 2 inch diameter), damaging gusts, and a few tornadoes will be possible from late Tuesday afternoon, into the evening and overnight from parts of the mid Mississippi Valley to the Ohio Valley and southern Lower Michigan. ...Synopsis... Upper pattern is forecast to feature a northern-stream shortwave trough over the northern Rockies early Tuesday morning. At the same time, moderate to strong southwesterly flow within the southern stream will extend from off the Baja coast into the Mid-South. The overall upper pattern will trend toward consolidation as the northern-stream shortwave progresses eastward and evolves into a full latitude trough covering much of the central CONUS by the end of the period early Wednesday morning. Surface low associated with this trough is expected to deepen as it moves across the Upper Midwest and Upper Great Lakes, with notable mass response and low-level moisture advection anticipated through the MS Valley. General expectation is for upper 50s dewpoints to reach the Lower/Middle OH Valley and perhaps even Lower MI by Tuesday evening. A fast-moving cold front attendant to the deepening surface low will progress quickly eastward/southeastward across the Plains and MS/OH Valleys, with thunderstorms anticipated as it interacts with the returning low-level moisture, particularly across the Mid-MS and Lower/Mid OH Valleys. ...Upper OH Valley Early Tuesday... Showers and thunderstorms will likely be ongoing over eastern OH, supported by moderate low-level southwesterly flow and associated warm-air advection regime. Cold mid-level temperatures and attendant steep mid-level lapse rates will support enough buoyancy for deep updrafts, with moderate deep-layer vertical shear contributing to some potential for updraft organization/rotation. As a result, some of these thunderstorms may become strong enough to produce hail. Limited buoyancy should lead to a gradually diminishing storm intensity with eastern extent. ...Mid-MS Valley into Lower/Middle OH Valley and southern Lower MI Tuesday evening and overnight... The airmass across the region is expected to gradually destabilize throughout the day amid a combination of increasing low-level moisture and cooling mid-level temperatures. Even so, the general expectation is for the open warm sector to remain capped throughout the day. Initial thunderstorm development will likely occur via warm advection in the vicinity of the warm front from far northeast IL across northern IN/OH and into Lower MI. The highest storm coverage is anticipated north of the warm front, with steep mid-level lapse rates and strong vertical shear supporting robust updrafts capable of large to very large hail within these elevated storms. There is some chance for storms to interact with the warm front, particularly if development occurs closer to the surface low, where thermodynamic conditions are more supportive of surface-based storms. Backed low-level flow is also possible in these areas, resulting in the potential for supercells capable of all severe hazards, including tornadoes. While the duration and coverage of early evening storms may impact thermodynamics, the general expectation is for another round of thunderstorms to develop along the cold front as it moves through. Initial development of these storms is anticipated from western IL into east-central/southeast MO in the 00-03Z timeframe, with the storms then tracking eastward with the cold front. Most favorable low-level moisture and buoyancy will likely be in place across IL and IN, with the greatest potential for damaging gusts in this region. Buoyancy will lessen with eastern extent into OH, with the expectation that storm intensity will lessen with eastern extent as well. ..Mosier.. 02/26/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Mon Feb 26 2024 Valid 261700Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN AND CENTRAL HIGH PLAINS... Minor adjustments were made to the Elevated area based on the most recent guidance. At least briefly elevated to near-critical fire weather is possible in parts of Missouri, eastern Iowa, and Illinois. Given the expected short duration and generally marginal fuels, no highlights will be added. ..Wendt.. 02/26/2024 .PREV DISCUSSION... /ISSUED 0201 AM CST Mon Feb 26 2024/ ...Synopsis... Strong westerly flow aloft is forecast to overspread much of the central US as an upstream Pacific trough begins to merge with an enhanced subtropical jet. A strong lee low and trailing surface trough will develop across the Plains bolstering surface winds. Widespread low humidity and warm temperatures accompanying the strong winds will support elevated to critical fire-weather conditions. ...Southern and central Plains... Increasingly strong flow aloft is expected to overspread the southern and central Rockies/High Plains through the day today. Aided by a strengthening lee trough and the flow aloft, gusty west/southwesterly surface winds are likely across much of the Plains. Unusually warm surface temperatures in the 70s and 80s F along with downslope drying will favor afternoon RH values of 15-20%. Meteorological conditions will likely support widespread critical fire-weather conditions across parts of eastern CO/NM into west TX and OK where area fuels have undergone significant drying. Farther north, stronger downslope winds are expected in the lee of the central Rockies along with RH below 20%. Updated fuel guidance points to slightly more receptive fuels than the previous days. Widespread elevated to near-critical fire-weather conditions are possible from eastern WY and western NE to portions of the Midwest. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Mon Feb 26 2024 Valid 261630Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE OHIO VALLEY AND GREAT LAKES... ...SUMMARY... Isolated late-night hail is possible across portions of the central Great Lakes region. ...Synopsis... A mid-level trough will dig across the Pacific Northwest today with a mostly zonal mid-level pattern across the eastern CONUS. Within that zonal flow, a weak shortwave trough is forecast to move through the Great Lakes/Ohio Valley late tonight and could result in some thunderstorms capable of large hail. A gradual strengthening of the low-level jet is anticipated through the day today from the Ohio Valley into the Great Lakes as a mid-level trough advances eastward. This will lead to poleward moisture transport centered around 850mb. This moist plume combined with very steep (8-8.5 C/km) mid-level lapse rates will lead to increasing elevated instability during the overnight period. Convective initiation remains the primary question during the overnight period. A trough is present at both 850mb and 500mb in 12Z guidance, but they are not quite phased. This leads to weakening/veering 850mb flow during the period when height falls and 500mb dCVA arrives across the region. This is likely an explanatory factor for the lack of storm coverage by most CAM guidance. Nonetheless, global guidance continues to show significant convective precipitation from southern Michigan to northern Tennessee. Given 1000 to 2000 J/kg MUCAPE and effective shear of 45-50 knots (highest across southern Indiana), a conditional threat for elevated supercells capable of large hail exists tonight. Have expanded the marginal risk farther south in Indiana to account for this threat. It is worth mentioning there is at least some threat farther south into Kentucky where strong instability and shear are present which would support supercells also. However, have confined the marginal risk to areas where better mid-level support is expected early Tuesday morning. ..Bentley.. 02/26/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Mon Feb 26 2024 Valid 261630Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE OHIO VALLEY AND GREAT LAKES... ...SUMMARY... Isolated late-night hail is possible across portions of the central Great Lakes region. ...Synopsis... A mid-level trough will dig across the Pacific Northwest today with a mostly zonal mid-level pattern across the eastern CONUS. Within that zonal flow, a weak shortwave trough is forecast to move through the Great Lakes/Ohio Valley late tonight and could result in some thunderstorms capable of large hail. A gradual strengthening of the low-level jet is anticipated through the day today from the Ohio Valley into the Great Lakes as a mid-level trough advances eastward. This will lead to poleward moisture transport centered around 850mb. This moist plume combined with very steep (8-8.5 C/km) mid-level lapse rates will lead to increasing elevated instability during the overnight period. Convective initiation remains the primary question during the overnight period. A trough is present at both 850mb and 500mb in 12Z guidance, but they are not quite phased. This leads to weakening/veering 850mb flow during the period when height falls and 500mb dCVA arrives across the region. This is likely an explanatory factor for the lack of storm coverage by most CAM guidance. Nonetheless, global guidance continues to show significant convective precipitation from southern Michigan to northern Tennessee. Given 1000 to 2000 J/kg MUCAPE and effective shear of 45-50 knots (highest across southern Indiana), a conditional threat for elevated supercells capable of large hail exists tonight. Have expanded the marginal risk farther south in Indiana to account for this threat. It is worth mentioning there is at least some threat farther south into Kentucky where strong instability and shear are present which would support supercells also. However, have confined the marginal risk to areas where better mid-level support is expected early Tuesday morning. ..Bentley.. 02/26/2024 Read more