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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0109 PM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... Strong offshore winds are still expected across southern California. Fuels will continue to be the mitigating factor to a greater fire-weather risk. Fuel drying that will occur with the low RH and strong winds is not expected to be sufficient for more than a locally elevated threat. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0200 AM CST Sun Nov 19 2023/ ...Synopsis... A deep upper trough over the Four Corners will begin to move eastward over the Plains and central US through Monday with an accompanying surface low and Pacific front. Very strong mid-level flow will overspread parts of the Southern High Plains, while surface high pressure develops within the Great Basin. Gusty winds are possible over parts of Southern CA and the southern High Plains, but recent rainfall and cooler conditions should keep fire-weather concerns localized. ...Southern Plains... To the east of the deepening Four Corners trough, very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the upper-level systems begins to move east. Aided by the low over central OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns before weakening late Monday. ...Southern California... As the main upper trough continues to deepen, strong flow aloft along the backside will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through Monday evening before winds begin to weaken into Tuesday morning. However, recent rain and the relatively brief period of offshore winds suggests any fire-weather concerns will remain localized, with only marginally receptive fuels. ...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 0109 PM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... Strong offshore winds are still expected across southern California. Fuels will continue to be the mitigating factor to a greater fire-weather risk. Fuel drying that will occur with the low RH and strong winds is not expected to be sufficient for more than a locally elevated threat. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0200 AM CST Sun Nov 19 2023/ ...Synopsis... A deep upper trough over the Four Corners will begin to move eastward over the Plains and central US through Monday with an accompanying surface low and Pacific front. Very strong mid-level flow will overspread parts of the Southern High Plains, while surface high pressure develops within the Great Basin. Gusty winds are possible over parts of Southern CA and the southern High Plains, but recent rainfall and cooler conditions should keep fire-weather concerns localized. ...Southern Plains... To the east of the deepening Four Corners trough, very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the upper-level systems begins to move east. Aided by the low over central OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns before weakening late Monday. ...Southern California... As the main upper trough continues to deepen, strong flow aloft along the backside will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through Monday evening before winds begin to weaken into Tuesday morning. However, recent rain and the relatively brief period of offshore winds suggests any fire-weather concerns will remain localized, with only marginally receptive fuels. ...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 0109 PM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... Strong offshore winds are still expected across southern California. Fuels will continue to be the mitigating factor to a greater fire-weather risk. Fuel drying that will occur with the low RH and strong winds is not expected to be sufficient for more than a locally elevated threat. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0200 AM CST Sun Nov 19 2023/ ...Synopsis... A deep upper trough over the Four Corners will begin to move eastward over the Plains and central US through Monday with an accompanying surface low and Pacific front. Very strong mid-level flow will overspread parts of the Southern High Plains, while surface high pressure develops within the Great Basin. Gusty winds are possible over parts of Southern CA and the southern High Plains, but recent rainfall and cooler conditions should keep fire-weather concerns localized. ...Southern Plains... To the east of the deepening Four Corners trough, very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the upper-level systems begins to move east. Aided by the low over central OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns before weakening late Monday. ...Southern California... As the main upper trough continues to deepen, strong flow aloft along the backside will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through Monday evening before winds begin to weaken into Tuesday morning. However, recent rain and the relatively brief period of offshore winds suggests any fire-weather concerns will remain localized, with only marginally receptive fuels. ...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 0109 PM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... Strong offshore winds are still expected across southern California. Fuels will continue to be the mitigating factor to a greater fire-weather risk. Fuel drying that will occur with the low RH and strong winds is not expected to be sufficient for more than a locally elevated threat. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0200 AM CST Sun Nov 19 2023/ ...Synopsis... A deep upper trough over the Four Corners will begin to move eastward over the Plains and central US through Monday with an accompanying surface low and Pacific front. Very strong mid-level flow will overspread parts of the Southern High Plains, while surface high pressure develops within the Great Basin. Gusty winds are possible over parts of Southern CA and the southern High Plains, but recent rainfall and cooler conditions should keep fire-weather concerns localized. ...Southern Plains... To the east of the deepening Four Corners trough, very strong flow aloft is expected to overspread parts of the Southern High Plains and eastern NM as the upper-level systems begins to move east. Aided by the low over central OK, gusty northwest surface winds are possible across west TX and eastern NM Monday afternoon and evening. However, recent rainfall and cooler temperatures in the wake of the passing Pacific front should keep RH above critical levels. Gusty winds still may support brief local fire-weather concerns before weakening late Monday. ...Southern California... As the main upper trough continues to deepen, strong flow aloft along the backside will overspread parts of southern CA late this weekend into early Monday. High pressure over the Great Basin will tighten offshore surface pressure gradients, enhancing surface winds across Point Conception and the lee of the Peninsular Ranges. A few hours of gusty winds and low humidity are likely through Monday evening before winds begin to weaken into Tuesday morning. However, recent rain and the relatively brief period of offshore winds suggests any fire-weather concerns will remain localized, with only marginally receptive fuels. ...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 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sun Nov 19 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF NORTHERN LOUISIANA AND CENTRAL MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely Monday afternoon into Monday night from east Texas into parts of the Lower-Mississippi Valley and Southeast. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. However, some large hail is also possible. ...Synopsis... A strong mid-level jet streak across Texas will shift east during the day and into the mid-Mississippi Valley by Monday night. A surface low will move eastward through the day from near the Red River, into the Mid-Mississippi Valley, and then occlude northward into the Lower-Ohio Valley by early Tuesday morning. A warm front will move north during the day across the Lower-Mississippi Valley and bring mid-60s dewpoints into the I-20 corridor during the afternoon. Thunderstorm activity is expected along and primarily ahead of a cold front which will move from east Texas Monday afternoon to central/east-central Mississippi by 12Z Tuesday. ...Portions of northern Louisiana and central Mississippi... Expect relatively early convective initiation across east-central Texas, near the nose of the mid-level jet, where morning low temperatures will be in the mid to upper 60s with convective temperatures in the low 70s amid at least broken cloud cover. While shear will be strong (50+ knots), expect storm intensification to be gradual given ~750 MLCAPE and limited inhibition. However, by mid-afternoon as storms move into Louisiana, expect more robust storm development as instability increases and forcing for ascent intensifies as the mid-level trough starts to become more negatively tilted. Significant mass response is expected after 21Z which will lead to a strengthening low-level jet and low-level shear. This timing will correspond well to peak diurnal heating and supercell intensity. As hodographs elongate between 21Z and 00Z, the low-level wind profile will become increasingly favorable with nearly pure streamwise vorticity in the lowest 750m of most forecast soundings. Most CAM guidance shows mature supercells in the region at this time which would support tornado potential, some potentially strong. Diurnal thunderstorm activity is expected to become more linear through the evening with an increasing damaging wind threat. However, as the low-level jet intensifies, increasing isentropic ascent may be sufficient for additional warm-sector supercell development across Mississippi during the evening and into the overnight hours. The less favorable diurnal timing casts some doubt on the intensity of these supercells, but the wind profile will be extremely favorable (300+ m2/s2 0-500m SRH). Therefore, any strong supercells which develop in this region after dark would pose some strong tornado threat. ...Mid-Mississippi Valley... The majority of 12Z CAM guidance shows a surface low track across northwest Mississippi. Therefore, the categorical Slight risk closely matches this mean surface low track. However, some guidance has a farther north track, most notably the FV3 near the MO Bootheel. Therefore since the Marginal risk is conditional on the surface low track, it now extends to the MO Bootheel, indicating the most likely northernmost extent of any potential threat for isolated damaging wind gusts from a low-CAPE convective line along the surface front. ..Bentley.. 11/19/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1033 AM CST Sun Nov 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sun Nov 19 2023/ ...Synopsis... A broad western US trough is forecast to amplify considerably through the period as it digs southeastward toward the Four Corners later tonight. Strong mid-level flow along the back of the trough will move onshore over the West Coast as Pacific ridging intensifies farther west. Surface high pressure will intensify over the northern Great Basin, helping to strengthen surface pressure gradients over parts of southern CA late tonight into early Monday. Gusty winds are possible over parts of southern CA and the lower CO River Valley. However, recent precipitation and only modest RH decreases should keep fire-weather concerns low. Fire-weather concerns are also expected to remain localized across the southern Appalachians and TN Valley where high pressure will support dry surface conditions, but weak winds. ...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 Sun Nov 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sun Nov 19 2023/ ...Synopsis... A broad western US trough is forecast to amplify considerably through the period as it digs southeastward toward the Four Corners later tonight. Strong mid-level flow along the back of the trough will move onshore over the West Coast as Pacific ridging intensifies farther west. Surface high pressure will intensify over the northern Great Basin, helping to strengthen surface pressure gradients over parts of southern CA late tonight into early Monday. Gusty winds are possible over parts of southern CA and the lower CO River Valley. However, recent precipitation and only modest RH decreases should keep fire-weather concerns low. Fire-weather concerns are also expected to remain localized across the southern Appalachians and TN Valley where high pressure will support dry surface conditions, but weak winds. ...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 Sun Nov 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sun Nov 19 2023/ ...Synopsis... A broad western US trough is forecast to amplify considerably through the period as it digs southeastward toward the Four Corners later tonight. Strong mid-level flow along the back of the trough will move onshore over the West Coast as Pacific ridging intensifies farther west. Surface high pressure will intensify over the northern Great Basin, helping to strengthen surface pressure gradients over parts of southern CA late tonight into early Monday. Gusty winds are possible over parts of southern CA and the lower CO River Valley. However, recent precipitation and only modest RH decreases should keep fire-weather concerns low. Fire-weather concerns are also expected to remain localized across the southern Appalachians and TN Valley where high pressure will support dry surface conditions, but weak winds. ...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 Sun Nov 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sun Nov 19 2023/ ...Synopsis... A broad western US trough is forecast to amplify considerably through the period as it digs southeastward toward the Four Corners later tonight. Strong mid-level flow along the back of the trough will move onshore over the West Coast as Pacific ridging intensifies farther west. Surface high pressure will intensify over the northern Great Basin, helping to strengthen surface pressure gradients over parts of southern CA late tonight into early Monday. Gusty winds are possible over parts of southern CA and the lower CO River Valley. However, recent precipitation and only modest RH decreases should keep fire-weather concerns low. Fire-weather concerns are also expected to remain localized across the southern Appalachians and TN Valley where high pressure will support dry surface conditions, but weak winds. ...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 Sun Nov 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 11/19/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sun Nov 19 2023/ ...Synopsis... A broad western US trough is forecast to amplify considerably through the period as it digs southeastward toward the Four Corners later tonight. Strong mid-level flow along the back of the trough will move onshore over the West Coast as Pacific ridging intensifies farther west. Surface high pressure will intensify over the northern Great Basin, helping to strengthen surface pressure gradients over parts of southern CA late tonight into early Monday. Gusty winds are possible over parts of southern CA and the lower CO River Valley. However, recent precipitation and only modest RH decreases should keep fire-weather concerns low. Fire-weather concerns are also expected to remain localized across the southern Appalachians and TN Valley where high pressure will support dry surface conditions, but weak winds. ...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 1027 AM CST Sun Nov 19 2023 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER CENTRAL AND NORTHERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of Oklahoma. ...Central/northern Oklahoma... Multiple, mostly low amplitude, mid-level perturbations were observed rotating around a large upper trough over the western/central U.S. as of 16z. A broad, meridionally elongated, area of surface low pressure extending from western KS southward into the TX Panhandle late this morning will gradually consolidate over southwest OK vicinity through tonight. Multiple rounds of showers and thunderstorms will continue today across portions of KS, OK and northern TX within a zone of low-level warm advection and aided by ascent with lead impulses. With time, cooling mid-level temperatures as the upper trough approaches and continued low-level warm/moist advection will support MUCAPE of 500-locally 1000 J/kg over OK this evening and tonight. Effective shear values of 30-40 kts will lead to sufficient updraft organization for a few stronger elevated storms to be capable of marginally severe hail. ..Bunting/Kerr.. 11/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sun Nov 19 2023 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER CENTRAL AND NORTHERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of Oklahoma. ...Central/northern Oklahoma... Multiple, mostly low amplitude, mid-level perturbations were observed rotating around a large upper trough over the western/central U.S. as of 16z. A broad, meridionally elongated, area of surface low pressure extending from western KS southward into the TX Panhandle late this morning will gradually consolidate over southwest OK vicinity through tonight. Multiple rounds of showers and thunderstorms will continue today across portions of KS, OK and northern TX within a zone of low-level warm advection and aided by ascent with lead impulses. With time, cooling mid-level temperatures as the upper trough approaches and continued low-level warm/moist advection will support MUCAPE of 500-locally 1000 J/kg over OK this evening and tonight. Effective shear values of 30-40 kts will lead to sufficient updraft organization for a few stronger elevated storms to be capable of marginally severe hail. ..Bunting/Kerr.. 11/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sun Nov 19 2023 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER CENTRAL AND NORTHERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of Oklahoma. ...Central/northern Oklahoma... Multiple, mostly low amplitude, mid-level perturbations were observed rotating around a large upper trough over the western/central U.S. as of 16z. A broad, meridionally elongated, area of surface low pressure extending from western KS southward into the TX Panhandle late this morning will gradually consolidate over southwest OK vicinity through tonight. Multiple rounds of showers and thunderstorms will continue today across portions of KS, OK and northern TX within a zone of low-level warm advection and aided by ascent with lead impulses. With time, cooling mid-level temperatures as the upper trough approaches and continued low-level warm/moist advection will support MUCAPE of 500-locally 1000 J/kg over OK this evening and tonight. Effective shear values of 30-40 kts will lead to sufficient updraft organization for a few stronger elevated storms to be capable of marginally severe hail. ..Bunting/Kerr.. 11/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sun Nov 19 2023 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER CENTRAL AND NORTHERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of Oklahoma. ...Central/northern Oklahoma... Multiple, mostly low amplitude, mid-level perturbations were observed rotating around a large upper trough over the western/central U.S. as of 16z. A broad, meridionally elongated, area of surface low pressure extending from western KS southward into the TX Panhandle late this morning will gradually consolidate over southwest OK vicinity through tonight. Multiple rounds of showers and thunderstorms will continue today across portions of KS, OK and northern TX within a zone of low-level warm advection and aided by ascent with lead impulses. With time, cooling mid-level temperatures as the upper trough approaches and continued low-level warm/moist advection will support MUCAPE of 500-locally 1000 J/kg over OK this evening and tonight. Effective shear values of 30-40 kts will lead to sufficient updraft organization for a few stronger elevated storms to be capable of marginally severe hail. ..Bunting/Kerr.. 11/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sun Nov 19 2023 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER CENTRAL AND NORTHERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of Oklahoma. ...Central/northern Oklahoma... Multiple, mostly low amplitude, mid-level perturbations were observed rotating around a large upper trough over the western/central U.S. as of 16z. A broad, meridionally elongated, area of surface low pressure extending from western KS southward into the TX Panhandle late this morning will gradually consolidate over southwest OK vicinity through tonight. Multiple rounds of showers and thunderstorms will continue today across portions of KS, OK and northern TX within a zone of low-level warm advection and aided by ascent with lead impulses. With time, cooling mid-level temperatures as the upper trough approaches and continued low-level warm/moist advection will support MUCAPE of 500-locally 1000 J/kg over OK this evening and tonight. Effective shear values of 30-40 kts will lead to sufficient updraft organization for a few stronger elevated storms to be capable of marginally severe hail. ..Bunting/Kerr.. 11/19/2023 Read more