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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR EAST TEXAS...CENTRAL LOUISIANA AND SOUTHWEST MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely this afternoon into tonight from east Texas, into parts of the Lower-Mississippi Valley, and Southeast States. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. Though damaging winds and some large hail are also possible. ...Synopsis... A broad positively tilted mid-level trough and jet streak over the southern Rockies is forecast to consolidate and strengthen rapidly into an upper low moving over the Southern Plains and the lower Mississippi Valley by late tonight. Several more neutral to negatively tilted shortwave perturbations embedded within the 80-90 kt jet streak will round the base of the trough and eject over the ArkLaTex and Southeast ahead of the main trough this afternoon. Broad diffluence and strong forcing for ascent will aid a surface low over OK as it moves northeastward toward the Mississippi River tonight. Strong low-level mass response ahead of the trough and the surface low should draw a warm front with rich low-level moisture (dewpoints in the 60s F) as far north as the MS/TN border. While mid-level lapse rates are modest, strong differential thermal advection and ascent should allow for the development of weak to moderate buoyancy sufficient for scattered severe storms over parts of the ArklaTex and Southeast states this afternoon into tonight. ...East TX into the lower Mississippi Valley... A complex convective evolution is expected today with widespread showers and thunderstorms likely to be ongoing north and east of the surface warm front across eastern OK, AR and parts of northeast TX at the start of the period. Isentropic ascent should remain strong through the morning hours with weak showers and broken to overcast skies likely throughout the warm sector. While this will likely inhibit surface heating to some degree, a few cloud breaks and low-level warm advection along a pre-frontal confluence axis in east TX should allow for weak to moderate destabilization and scattered storm development by mid morning to early afternoon. Veered surface flow with relatively weak shear and high RH in the low-levels suggests a messy storm evolution with early updrafts. However, strong line-normal mid and upper-level shear components should allow for the gradual intensification of individual supercell structures within a broader cluster or broken line ahead of the surface cold front across east-central TX. Albeit gradual, owing to modest low and mid-level lapse rates, the maturation of these storms through the mid to later afternoon will eventually overlap with a strongly sheared-low-level air mass as the main upper jet ejects over parts of far east TX, southern AR, and LA. 0-500m SRH of 100-150 m2/s2 and STP values of 2-3 will likely support strong low-level mesocyclones with the potential for tornadoes, some of which could be strong. These storms should continue eastward through the evening hours with a risk for tornadoes before gradual upscale growth into a loose QLCS increases the potential for damaging winds over central and eastern MS into western AL. Across parts of eastern AR into western/central TN and northern MS/AL, low-level destabilization appears much less favorable with multiple rounds of warm advection precipitation ahead of the surface low and main trough. A few model solutions bring the warm front far enough north to generate some positive near-surface buoyancy immediately ahead of the cold front. A fine-line QLCS may evolve with a low-end risk for damaging wind gusts given mixing of the strong background wind field to the surface. ...Southern AL and Gulf Coast tonight... As the warm front lifts north over parts of southeastern LA and southern MS this afternoon and evening, rich Gulf moisture will move quickly inland beneath a 30-40 kt low-level jet. While it is uncertain if storms can develop given modest forcing, a few supercells may evolve within the warm sector and track northeastward toward the strongly sheared frontal zone. A few tornadoes could develop in the evening hours ahead of the main band of convection farther west. Later tonight, the storms ahead of the cold front should gradually coalesce into a QLCS as the front shifts eastward. With strong low-level wind fields and at least some buoyancy remaining in place, damaging gusts and isolated tornadoes are possible well into the overnight hours across southeastern MS, southwest AL and possibly the western FL Panhandle. However, confidence in the eastward extent of the severe risk will depend greatly on the onshore destabilization which, given the diurnal timing, is not a guarantee. ..Lyons/Darrow.. 11/20/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR EAST TEXAS...CENTRAL LOUISIANA AND SOUTHWEST MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely this afternoon into tonight from east Texas, into parts of the Lower-Mississippi Valley, and Southeast States. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. Though damaging winds and some large hail are also possible. ...Synopsis... A broad positively tilted mid-level trough and jet streak over the southern Rockies is forecast to consolidate and strengthen rapidly into an upper low moving over the Southern Plains and the lower Mississippi Valley by late tonight. Several more neutral to negatively tilted shortwave perturbations embedded within the 80-90 kt jet streak will round the base of the trough and eject over the ArkLaTex and Southeast ahead of the main trough this afternoon. Broad diffluence and strong forcing for ascent will aid a surface low over OK as it moves northeastward toward the Mississippi River tonight. Strong low-level mass response ahead of the trough and the surface low should draw a warm front with rich low-level moisture (dewpoints in the 60s F) as far north as the MS/TN border. While mid-level lapse rates are modest, strong differential thermal advection and ascent should allow for the development of weak to moderate buoyancy sufficient for scattered severe storms over parts of the ArklaTex and Southeast states this afternoon into tonight. ...East TX into the lower Mississippi Valley... A complex convective evolution is expected today with widespread showers and thunderstorms likely to be ongoing north and east of the surface warm front across eastern OK, AR and parts of northeast TX at the start of the period. Isentropic ascent should remain strong through the morning hours with weak showers and broken to overcast skies likely throughout the warm sector. While this will likely inhibit surface heating to some degree, a few cloud breaks and low-level warm advection along a pre-frontal confluence axis in east TX should allow for weak to moderate destabilization and scattered storm development by mid morning to early afternoon. Veered surface flow with relatively weak shear and high RH in the low-levels suggests a messy storm evolution with early updrafts. However, strong line-normal mid and upper-level shear components should allow for the gradual intensification of individual supercell structures within a broader cluster or broken line ahead of the surface cold front across east-central TX. Albeit gradual, owing to modest low and mid-level lapse rates, the maturation of these storms through the mid to later afternoon will eventually overlap with a strongly sheared-low-level air mass as the main upper jet ejects over parts of far east TX, southern AR, and LA. 0-500m SRH of 100-150 m2/s2 and STP values of 2-3 will likely support strong low-level mesocyclones with the potential for tornadoes, some of which could be strong. These storms should continue eastward through the evening hours with a risk for tornadoes before gradual upscale growth into a loose QLCS increases the potential for damaging winds over central and eastern MS into western AL. Across parts of eastern AR into western/central TN and northern MS/AL, low-level destabilization appears much less favorable with multiple rounds of warm advection precipitation ahead of the surface low and main trough. A few model solutions bring the warm front far enough north to generate some positive near-surface buoyancy immediately ahead of the cold front. A fine-line QLCS may evolve with a low-end risk for damaging wind gusts given mixing of the strong background wind field to the surface. ...Southern AL and Gulf Coast tonight... As the warm front lifts north over parts of southeastern LA and southern MS this afternoon and evening, rich Gulf moisture will move quickly inland beneath a 30-40 kt low-level jet. While it is uncertain if storms can develop given modest forcing, a few supercells may evolve within the warm sector and track northeastward toward the strongly sheared frontal zone. A few tornadoes could develop in the evening hours ahead of the main band of convection farther west. Later tonight, the storms ahead of the cold front should gradually coalesce into a QLCS as the front shifts eastward. With strong low-level wind fields and at least some buoyancy remaining in place, damaging gusts and isolated tornadoes are possible well into the overnight hours across southeastern MS, southwest AL and possibly the western FL Panhandle. However, confidence in the eastward extent of the severe risk will depend greatly on the onshore destabilization which, given the diurnal timing, is not a guarantee. ..Lyons/Darrow.. 11/20/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR EAST TEXAS...CENTRAL LOUISIANA AND SOUTHWEST MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely this afternoon into tonight from east Texas, into parts of the Lower-Mississippi Valley, and Southeast States. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. Though damaging winds and some large hail are also possible. ...Synopsis... A broad positively tilted mid-level trough and jet streak over the southern Rockies is forecast to consolidate and strengthen rapidly into an upper low moving over the Southern Plains and the lower Mississippi Valley by late tonight. Several more neutral to negatively tilted shortwave perturbations embedded within the 80-90 kt jet streak will round the base of the trough and eject over the ArkLaTex and Southeast ahead of the main trough this afternoon. Broad diffluence and strong forcing for ascent will aid a surface low over OK as it moves northeastward toward the Mississippi River tonight. Strong low-level mass response ahead of the trough and the surface low should draw a warm front with rich low-level moisture (dewpoints in the 60s F) as far north as the MS/TN border. While mid-level lapse rates are modest, strong differential thermal advection and ascent should allow for the development of weak to moderate buoyancy sufficient for scattered severe storms over parts of the ArklaTex and Southeast states this afternoon into tonight. ...East TX into the lower Mississippi Valley... A complex convective evolution is expected today with widespread showers and thunderstorms likely to be ongoing north and east of the surface warm front across eastern OK, AR and parts of northeast TX at the start of the period. Isentropic ascent should remain strong through the morning hours with weak showers and broken to overcast skies likely throughout the warm sector. While this will likely inhibit surface heating to some degree, a few cloud breaks and low-level warm advection along a pre-frontal confluence axis in east TX should allow for weak to moderate destabilization and scattered storm development by mid morning to early afternoon. Veered surface flow with relatively weak shear and high RH in the low-levels suggests a messy storm evolution with early updrafts. However, strong line-normal mid and upper-level shear components should allow for the gradual intensification of individual supercell structures within a broader cluster or broken line ahead of the surface cold front across east-central TX. Albeit gradual, owing to modest low and mid-level lapse rates, the maturation of these storms through the mid to later afternoon will eventually overlap with a strongly sheared-low-level air mass as the main upper jet ejects over parts of far east TX, southern AR, and LA. 0-500m SRH of 100-150 m2/s2 and STP values of 2-3 will likely support strong low-level mesocyclones with the potential for tornadoes, some of which could be strong. These storms should continue eastward through the evening hours with a risk for tornadoes before gradual upscale growth into a loose QLCS increases the potential for damaging winds over central and eastern MS into western AL. Across parts of eastern AR into western/central TN and northern MS/AL, low-level destabilization appears much less favorable with multiple rounds of warm advection precipitation ahead of the surface low and main trough. A few model solutions bring the warm front far enough north to generate some positive near-surface buoyancy immediately ahead of the cold front. A fine-line QLCS may evolve with a low-end risk for damaging wind gusts given mixing of the strong background wind field to the surface. ...Southern AL and Gulf Coast tonight... As the warm front lifts north over parts of southeastern LA and southern MS this afternoon and evening, rich Gulf moisture will move quickly inland beneath a 30-40 kt low-level jet. While it is uncertain if storms can develop given modest forcing, a few supercells may evolve within the warm sector and track northeastward toward the strongly sheared frontal zone. A few tornadoes could develop in the evening hours ahead of the main band of convection farther west. Later tonight, the storms ahead of the cold front should gradually coalesce into a QLCS as the front shifts eastward. With strong low-level wind fields and at least some buoyancy remaining in place, damaging gusts and isolated tornadoes are possible well into the overnight hours across southeastern MS, southwest AL and possibly the western FL Panhandle. However, confidence in the eastward extent of the severe risk will depend greatly on the onshore destabilization which, given the diurnal timing, is not a guarantee. ..Lyons/Darrow.. 11/20/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR EAST TEXAS...CENTRAL LOUISIANA AND SOUTHWEST MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely this afternoon into tonight from east Texas, into parts of the Lower-Mississippi Valley, and Southeast States. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. Though damaging winds and some large hail are also possible. ...Synopsis... A broad positively tilted mid-level trough and jet streak over the southern Rockies is forecast to consolidate and strengthen rapidly into an upper low moving over the Southern Plains and the lower Mississippi Valley by late tonight. Several more neutral to negatively tilted shortwave perturbations embedded within the 80-90 kt jet streak will round the base of the trough and eject over the ArkLaTex and Southeast ahead of the main trough this afternoon. Broad diffluence and strong forcing for ascent will aid a surface low over OK as it moves northeastward toward the Mississippi River tonight. Strong low-level mass response ahead of the trough and the surface low should draw a warm front with rich low-level moisture (dewpoints in the 60s F) as far north as the MS/TN border. While mid-level lapse rates are modest, strong differential thermal advection and ascent should allow for the development of weak to moderate buoyancy sufficient for scattered severe storms over parts of the ArklaTex and Southeast states this afternoon into tonight. ...East TX into the lower Mississippi Valley... A complex convective evolution is expected today with widespread showers and thunderstorms likely to be ongoing north and east of the surface warm front across eastern OK, AR and parts of northeast TX at the start of the period. Isentropic ascent should remain strong through the morning hours with weak showers and broken to overcast skies likely throughout the warm sector. While this will likely inhibit surface heating to some degree, a few cloud breaks and low-level warm advection along a pre-frontal confluence axis in east TX should allow for weak to moderate destabilization and scattered storm development by mid morning to early afternoon. Veered surface flow with relatively weak shear and high RH in the low-levels suggests a messy storm evolution with early updrafts. However, strong line-normal mid and upper-level shear components should allow for the gradual intensification of individual supercell structures within a broader cluster or broken line ahead of the surface cold front across east-central TX. Albeit gradual, owing to modest low and mid-level lapse rates, the maturation of these storms through the mid to later afternoon will eventually overlap with a strongly sheared-low-level air mass as the main upper jet ejects over parts of far east TX, southern AR, and LA. 0-500m SRH of 100-150 m2/s2 and STP values of 2-3 will likely support strong low-level mesocyclones with the potential for tornadoes, some of which could be strong. These storms should continue eastward through the evening hours with a risk for tornadoes before gradual upscale growth into a loose QLCS increases the potential for damaging winds over central and eastern MS into western AL. Across parts of eastern AR into western/central TN and northern MS/AL, low-level destabilization appears much less favorable with multiple rounds of warm advection precipitation ahead of the surface low and main trough. A few model solutions bring the warm front far enough north to generate some positive near-surface buoyancy immediately ahead of the cold front. A fine-line QLCS may evolve with a low-end risk for damaging wind gusts given mixing of the strong background wind field to the surface. ...Southern AL and Gulf Coast tonight... As the warm front lifts north over parts of southeastern LA and southern MS this afternoon and evening, rich Gulf moisture will move quickly inland beneath a 30-40 kt low-level jet. While it is uncertain if storms can develop given modest forcing, a few supercells may evolve within the warm sector and track northeastward toward the strongly sheared frontal zone. A few tornadoes could develop in the evening hours ahead of the main band of convection farther west. Later tonight, the storms ahead of the cold front should gradually coalesce into a QLCS as the front shifts eastward. With strong low-level wind fields and at least some buoyancy remaining in place, damaging gusts and isolated tornadoes are possible well into the overnight hours across southeastern MS, southwest AL and possibly the western FL Panhandle. However, confidence in the eastward extent of the severe risk will depend greatly on the onshore destabilization which, given the diurnal timing, is not a guarantee. ..Lyons/Darrow.. 11/20/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Mon Nov 20 2023 Valid 201200Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF FAR EAST TEXAS...CENTRAL LOUISIANA AND SOUTHWEST MISSISSIPPI... ...SUMMARY... Severe thunderstorms are likely this afternoon into tonight from east Texas, into parts of the Lower-Mississippi Valley, and Southeast States. Damaging winds and several tornadoes, a few of which may be strong, will be the primary hazards. Though damaging winds and some large hail are also possible. ...Synopsis... A broad positively tilted mid-level trough and jet streak over the southern Rockies is forecast to consolidate and strengthen rapidly into an upper low moving over the Southern Plains and the lower Mississippi Valley by late tonight. Several more neutral to negatively tilted shortwave perturbations embedded within the 80-90 kt jet streak will round the base of the trough and eject over the ArkLaTex and Southeast ahead of the main trough this afternoon. Broad diffluence and strong forcing for ascent will aid a surface low over OK as it moves northeastward toward the Mississippi River tonight. Strong low-level mass response ahead of the trough and the surface low should draw a warm front with rich low-level moisture (dewpoints in the 60s F) as far north as the MS/TN border. While mid-level lapse rates are modest, strong differential thermal advection and ascent should allow for the development of weak to moderate buoyancy sufficient for scattered severe storms over parts of the ArklaTex and Southeast states this afternoon into tonight. ...East TX into the lower Mississippi Valley... A complex convective evolution is expected today with widespread showers and thunderstorms likely to be ongoing north and east of the surface warm front across eastern OK, AR and parts of northeast TX at the start of the period. Isentropic ascent should remain strong through the morning hours with weak showers and broken to overcast skies likely throughout the warm sector. While this will likely inhibit surface heating to some degree, a few cloud breaks and low-level warm advection along a pre-frontal confluence axis in east TX should allow for weak to moderate destabilization and scattered storm development by mid morning to early afternoon. Veered surface flow with relatively weak shear and high RH in the low-levels suggests a messy storm evolution with early updrafts. However, strong line-normal mid and upper-level shear components should allow for the gradual intensification of individual supercell structures within a broader cluster or broken line ahead of the surface cold front across east-central TX. Albeit gradual, owing to modest low and mid-level lapse rates, the maturation of these storms through the mid to later afternoon will eventually overlap with a strongly sheared-low-level air mass as the main upper jet ejects over parts of far east TX, southern AR, and LA. 0-500m SRH of 100-150 m2/s2 and STP values of 2-3 will likely support strong low-level mesocyclones with the potential for tornadoes, some of which could be strong. These storms should continue eastward through the evening hours with a risk for tornadoes before gradual upscale growth into a loose QLCS increases the potential for damaging winds over central and eastern MS into western AL. Across parts of eastern AR into western/central TN and northern MS/AL, low-level destabilization appears much less favorable with multiple rounds of warm advection precipitation ahead of the surface low and main trough. A few model solutions bring the warm front far enough north to generate some positive near-surface buoyancy immediately ahead of the cold front. A fine-line QLCS may evolve with a low-end risk for damaging wind gusts given mixing of the strong background wind field to the surface. ...Southern AL and Gulf Coast tonight... As the warm front lifts north over parts of southeastern LA and southern MS this afternoon and evening, rich Gulf moisture will move quickly inland beneath a 30-40 kt low-level jet. While it is uncertain if storms can develop given modest forcing, a few supercells may evolve within the warm sector and track northeastward toward the strongly sheared frontal zone. A few tornadoes could develop in the evening hours ahead of the main band of convection farther west. Later tonight, the storms ahead of the cold front should gradually coalesce into a QLCS as the front shifts eastward. With strong low-level wind fields and at least some buoyancy remaining in place, damaging gusts and isolated tornadoes are possible well into the overnight hours across southeastern MS, southwest AL and possibly the western FL Panhandle. However, confidence in the eastward extent of the severe risk will depend greatly on the onshore destabilization which, given the diurnal timing, is not a guarantee. ..Lyons/Darrow.. 11/20/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 PM CST Sun Nov 19 2023 Valid 200100Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND EASTERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of central and eastern Oklahoma. ...01z Update... Evening water vapor imagery showed a broad mid-level trough centered over the Rockies with several well-defined shortwave troughs embedded within a strengthening basal speed max. As the first of these shortwave troughs departs the southern Plains into the Midwest, a second shortwave over the TX Panhandle will push eastward into OK late this evening and overnight. An initial lee low over the TX Panhandle will continue drawing mid 50s f surface dewpoints northward as it moves into central and eastern OK tonight. Cooling aloft associated with the shortwave and strong diffluence/qg forcing from the speed max should aid in scattered thunderstorm development tonight over central OK. Area model soundings are not overly impressive showing elevated MUCAPE of 500-750 J/kg developing beneath -18 to -20 C 500 mb temps beneath the western shortwave. Moderate deep-layer shear may also support brief organization of any stronger updrafts able to become established. A couple instances of marginally severe hail are possible with storms beneath the cold core aloft. However, confidence in severe coverage remains low given the marginal thermodynamic environment. Despite the uncertainty, a conditional risk for hail will necessitate keeping the MRGL risk in place over central and eastern OK. Opted for a slight southward expansion in severe probs for recent Hi-Res guidance trending father south with the more robust storms. Will also trim the northeastern most part of the MRGL where vertical shear is expected to be much weaker well north of the speed max. ..Lyons.. 11/20/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 PM CST Sun Nov 19 2023 Valid 200100Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND EASTERN OKLAHOMA... ...SUMMARY... Marginally severe hail may occur with evening/overnight thunderstorms in parts of central and eastern Oklahoma. ...01z Update... Evening water vapor imagery showed a broad mid-level trough centered over the Rockies with several well-defined shortwave troughs embedded within a strengthening basal speed max. As the first of these shortwave troughs departs the southern Plains into the Midwest, a second shortwave over the TX Panhandle will push eastward into OK late this evening and overnight. An initial lee low over the TX Panhandle will continue drawing mid 50s f surface dewpoints northward as it moves into central and eastern OK tonight. Cooling aloft associated with the shortwave and strong diffluence/qg forcing from the speed max should aid in scattered thunderstorm development tonight over central OK. Area model soundings are not overly impressive showing elevated MUCAPE of 500-750 J/kg developing beneath -18 to -20 C 500 mb temps beneath the western shortwave. Moderate deep-layer shear may also support brief organization of any stronger updrafts able to become established. A couple instances of marginally severe hail are possible with storms beneath the cold core aloft. However, confidence in severe coverage remains low given the marginal thermodynamic environment. Despite the uncertainty, a conditional risk for hail will necessitate keeping the MRGL risk in place over central and eastern OK. Opted for a slight southward expansion in severe probs for recent Hi-Res guidance trending father south with the more robust storms. Will also trim the northeastern most part of the MRGL where vertical shear is expected to be much weaker well north of the speed max. ..Lyons.. 11/20/2023 Read more

No watches are valid as of Sun Nov 19 22:27:02 UTC 2023.

No Mesoscale Discussions are in effect as of Sun Nov 19 22:27:02 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CST Sun Nov 19 2023 Valid 211200Z - 271200Z A potent upper-level trough will continue eastward and exit the East Coast by midweek. Low-amplitude ridging is expected to move over the central U.S. in the wake of this initial trough. Towards the end of the week, another upper-level trough will move southeastward within the western U.S. before ejecting into the Plains by the end of this week. Thereafter, broad troughing will develop east of the Divide with upper-level ridging becoming more prominent in the West. At the surface, a cold front will move off the Gulf Coast on Tuesday with high pressure remaining in the West. Another cold front is expected within the Plains around midweek and will eventually be pushed south by the weekend. Surface high pressure is expected to return in the West as upper-level ridging intensifies late next week. ...Southern High Plains... Precipitation across parts of the region should be a relative minimum compared to adjacent areas. Dry and windy conditions are possible in the post-frontal environment on Tuesday as well as with the approach of the next upper-level trough on Thursday. Models have trended toward more of a broad upper trough and less deepening of a surface low on Thursday so there is less certainty on the strength of the winds. Given the generally poor receptiveness of fuels, the potential for critical fire weather remains low both days. ...Southern California... Offshore pressure gradients are expected to increase again towards the end of this week into the weekend. With fuels likely to have dried some from the current offshore wind event, it is possible they will be more receptive for this upcoming event. That being said, the offshore gradients do appear weaker late next week and upper-level wind support is much less certain as well. Fuel and wind trends will be monitored, but confidence in critical fire weather is too low for highlights. ..Wendt.. 11/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CST Sun Nov 19 2023 Valid 211200Z - 271200Z A potent upper-level trough will continue eastward and exit the East Coast by midweek. Low-amplitude ridging is expected to move over the central U.S. in the wake of this initial trough. Towards the end of the week, another upper-level trough will move southeastward within the western U.S. before ejecting into the Plains by the end of this week. Thereafter, broad troughing will develop east of the Divide with upper-level ridging becoming more prominent in the West. At the surface, a cold front will move off the Gulf Coast on Tuesday with high pressure remaining in the West. Another cold front is expected within the Plains around midweek and will eventually be pushed south by the weekend. Surface high pressure is expected to return in the West as upper-level ridging intensifies late next week. ...Southern High Plains... Precipitation across parts of the region should be a relative minimum compared to adjacent areas. Dry and windy conditions are possible in the post-frontal environment on Tuesday as well as with the approach of the next upper-level trough on Thursday. Models have trended toward more of a broad upper trough and less deepening of a surface low on Thursday so there is less certainty on the strength of the winds. Given the generally poor receptiveness of fuels, the potential for critical fire weather remains low both days. ...Southern California... Offshore pressure gradients are expected to increase again towards the end of this week into the weekend. With fuels likely to have dried some from the current offshore wind event, it is possible they will be more receptive for this upcoming event. That being said, the offshore gradients do appear weaker late next week and upper-level wind support is much less certain as well. Fuel and wind trends will be monitored, but confidence in critical fire weather is too low for highlights. ..Wendt.. 11/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CST Sun Nov 19 2023 Valid 211200Z - 271200Z A potent upper-level trough will continue eastward and exit the East Coast by midweek. Low-amplitude ridging is expected to move over the central U.S. in the wake of this initial trough. Towards the end of the week, another upper-level trough will move southeastward within the western U.S. before ejecting into the Plains by the end of this week. Thereafter, broad troughing will develop east of the Divide with upper-level ridging becoming more prominent in the West. At the surface, a cold front will move off the Gulf Coast on Tuesday with high pressure remaining in the West. Another cold front is expected within the Plains around midweek and will eventually be pushed south by the weekend. Surface high pressure is expected to return in the West as upper-level ridging intensifies late next week. ...Southern High Plains... Precipitation across parts of the region should be a relative minimum compared to adjacent areas. Dry and windy conditions are possible in the post-frontal environment on Tuesday as well as with the approach of the next upper-level trough on Thursday. Models have trended toward more of a broad upper trough and less deepening of a surface low on Thursday so there is less certainty on the strength of the winds. Given the generally poor receptiveness of fuels, the potential for critical fire weather remains low both days. ...Southern California... Offshore pressure gradients are expected to increase again towards the end of this week into the weekend. With fuels likely to have dried some from the current offshore wind event, it is possible they will be more receptive for this upcoming event. That being said, the offshore gradients do appear weaker late next week and upper-level wind support is much less certain as well. Fuel and wind trends will be monitored, but confidence in critical fire weather is too low for highlights. ..Wendt.. 11/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CST Sun Nov 19 2023 Valid 211200Z - 271200Z A potent upper-level trough will continue eastward and exit the East Coast by midweek. Low-amplitude ridging is expected to move over the central U.S. in the wake of this initial trough. Towards the end of the week, another upper-level trough will move southeastward within the western U.S. before ejecting into the Plains by the end of this week. Thereafter, broad troughing will develop east of the Divide with upper-level ridging becoming more prominent in the West. At the surface, a cold front will move off the Gulf Coast on Tuesday with high pressure remaining in the West. Another cold front is expected within the Plains around midweek and will eventually be pushed south by the weekend. Surface high pressure is expected to return in the West as upper-level ridging intensifies late next week. ...Southern High Plains... Precipitation across parts of the region should be a relative minimum compared to adjacent areas. Dry and windy conditions are possible in the post-frontal environment on Tuesday as well as with the approach of the next upper-level trough on Thursday. Models have trended toward more of a broad upper trough and less deepening of a surface low on Thursday so there is less certainty on the strength of the winds. Given the generally poor receptiveness of fuels, the potential for critical fire weather remains low both days. ...Southern California... Offshore pressure gradients are expected to increase again towards the end of this week into the weekend. With fuels likely to have dried some from the current offshore wind event, it is possible they will be more receptive for this upcoming event. That being said, the offshore gradients do appear weaker late next week and upper-level wind support is much less certain as well. Fuel and wind trends will be monitored, but confidence in critical fire weather is too low for highlights. ..Wendt.. 11/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0342 PM CST Sun Nov 19 2023 Valid 211200Z - 271200Z A potent upper-level trough will continue eastward and exit the East Coast by midweek. Low-amplitude ridging is expected to move over the central U.S. in the wake of this initial trough. Towards the end of the week, another upper-level trough will move southeastward within the western U.S. before ejecting into the Plains by the end of this week. Thereafter, broad troughing will develop east of the Divide with upper-level ridging becoming more prominent in the West. At the surface, a cold front will move off the Gulf Coast on Tuesday with high pressure remaining in the West. Another cold front is expected within the Plains around midweek and will eventually be pushed south by the weekend. Surface high pressure is expected to return in the West as upper-level ridging intensifies late next week. ...Southern High Plains... Precipitation across parts of the region should be a relative minimum compared to adjacent areas. Dry and windy conditions are possible in the post-frontal environment on Tuesday as well as with the approach of the next upper-level trough on Thursday. Models have trended toward more of a broad upper trough and less deepening of a surface low on Thursday so there is less certainty on the strength of the winds. Given the generally poor receptiveness of fuels, the potential for critical fire weather remains low both days. ...Southern California... Offshore pressure gradients are expected to increase again towards the end of this week into the weekend. With fuels likely to have dried some from the current offshore wind event, it is possible they will be more receptive for this upcoming event. That being said, the offshore gradients do appear weaker late next week and upper-level wind support is much less certain as well. Fuel and wind trends will be monitored, but confidence in critical fire weather is too low for highlights. ..Wendt.. 11/19/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0140 PM CST Sun Nov 19 2023 Valid 192000Z - 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. Overnight elevated thunderstorm threat remains on track. Trimmed the western edge of general thunderstorm line across southwest Utah and northwest Arizona in the wake of the mid-level shortwave trough. ..Bentley.. 11/19/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sun Nov 19 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0140 PM CST Sun Nov 19 2023 Valid 192000Z - 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. Overnight elevated thunderstorm threat remains on track. Trimmed the western edge of general thunderstorm line across southwest Utah and northwest Arizona in the wake of the mid-level shortwave trough. ..Bentley.. 11/19/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sun Nov 19 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0140 PM CST Sun Nov 19 2023 Valid 192000Z - 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. Overnight elevated thunderstorm threat remains on track. Trimmed the western edge of general thunderstorm line across southwest Utah and northwest Arizona in the wake of the mid-level shortwave trough. ..Bentley.. 11/19/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sun Nov 19 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0140 PM CST Sun Nov 19 2023 Valid 192000Z - 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. Overnight elevated thunderstorm threat remains on track. Trimmed the western edge of general thunderstorm line across southwest Utah and northwest Arizona in the wake of the mid-level shortwave trough. ..Bentley.. 11/19/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sun Nov 19 2023/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0140 PM CST Sun Nov 19 2023 Valid 192000Z - 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. Overnight elevated thunderstorm threat remains on track. Trimmed the western edge of general thunderstorm line across southwest Utah and northwest Arizona in the wake of the mid-level shortwave trough. ..Bentley.. 11/19/2023 .PREV DISCUSSION... /ISSUED 1027 AM CST Sun Nov 19 2023/ ...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. 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