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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Sun Nov 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible Monday into Monday night from Louisiana into parts of the Mid-South, and also near the Oregon and northern California coasts. ...Synopsis... A strong mid/upper-level shortwave trough is forecast to take on a negative tilt on Monday, as it moves quickly eastward across parts of the Midwest and Ohio Valley. An associated surface low is forecast to move from IL toward lower MI through the day and evening, as a trailing cold front moves through parts of the Great Lakes, Ohio/Tennessee Valleys, and the mid/lower Mississippi Valley. Isolated thunderstorms may develop later Monday near the front from parts of LA into the Mid-South. Farther west, a mid/upper-level trough and embedded midlevel low are forecast are forecast to move eastward across parts of the Pacific Northwest, northern CA, and the Great Basin. Weak convection with isolated lightning flashes will be possible near the OR and northern CA coasts, in association with this trough. ...Parts of LA into the TN/OH Valleys... Low-level moisture return along/ahead of the cold front will result in 60s F dewpoints reaching as far north as the Mid-South by Monday afternoon, with 50s F dewpoints extending into parts of the Ohio Valley. Stronger large-scale ascent associated with the shortwave trough will be displaced to the north of the richer low-level moisture, and buoyancy is expected to generally remain weak. As a result, organized deep convection is currently not anticipated, despite the presence of favorable deep-layer shear. Generally weak convection with isolated thunderstorm potential will be possible (primarily later in the forecast period) in the vicinity of the front from parts of LA into the Mid-South. Weak low-topped convection (with localized gusty winds) will be possible into the Ohio Valley, but increasingly negligible buoyancy is expected to limit thunderstorm potential with northward extent. ..Dean.. 11/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Sun Nov 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible Monday into Monday night from Louisiana into parts of the Mid-South, and also near the Oregon and northern California coasts. ...Synopsis... A strong mid/upper-level shortwave trough is forecast to take on a negative tilt on Monday, as it moves quickly eastward across parts of the Midwest and Ohio Valley. An associated surface low is forecast to move from IL toward lower MI through the day and evening, as a trailing cold front moves through parts of the Great Lakes, Ohio/Tennessee Valleys, and the mid/lower Mississippi Valley. Isolated thunderstorms may develop later Monday near the front from parts of LA into the Mid-South. Farther west, a mid/upper-level trough and embedded midlevel low are forecast are forecast to move eastward across parts of the Pacific Northwest, northern CA, and the Great Basin. Weak convection with isolated lightning flashes will be possible near the OR and northern CA coasts, in association with this trough. ...Parts of LA into the TN/OH Valleys... Low-level moisture return along/ahead of the cold front will result in 60s F dewpoints reaching as far north as the Mid-South by Monday afternoon, with 50s F dewpoints extending into parts of the Ohio Valley. Stronger large-scale ascent associated with the shortwave trough will be displaced to the north of the richer low-level moisture, and buoyancy is expected to generally remain weak. As a result, organized deep convection is currently not anticipated, despite the presence of favorable deep-layer shear. Generally weak convection with isolated thunderstorm potential will be possible (primarily later in the forecast period) in the vicinity of the front from parts of LA into the Mid-South. Weak low-topped convection (with localized gusty winds) will be possible into the Ohio Valley, but increasingly negligible buoyancy is expected to limit thunderstorm potential with northward extent. ..Dean.. 11/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Sun Nov 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible Monday into Monday night from Louisiana into parts of the Mid-South, and also near the Oregon and northern California coasts. ...Synopsis... A strong mid/upper-level shortwave trough is forecast to take on a negative tilt on Monday, as it moves quickly eastward across parts of the Midwest and Ohio Valley. An associated surface low is forecast to move from IL toward lower MI through the day and evening, as a trailing cold front moves through parts of the Great Lakes, Ohio/Tennessee Valleys, and the mid/lower Mississippi Valley. Isolated thunderstorms may develop later Monday near the front from parts of LA into the Mid-South. Farther west, a mid/upper-level trough and embedded midlevel low are forecast are forecast to move eastward across parts of the Pacific Northwest, northern CA, and the Great Basin. Weak convection with isolated lightning flashes will be possible near the OR and northern CA coasts, in association with this trough. ...Parts of LA into the TN/OH Valleys... Low-level moisture return along/ahead of the cold front will result in 60s F dewpoints reaching as far north as the Mid-South by Monday afternoon, with 50s F dewpoints extending into parts of the Ohio Valley. Stronger large-scale ascent associated with the shortwave trough will be displaced to the north of the richer low-level moisture, and buoyancy is expected to generally remain weak. As a result, organized deep convection is currently not anticipated, despite the presence of favorable deep-layer shear. Generally weak convection with isolated thunderstorm potential will be possible (primarily later in the forecast period) in the vicinity of the front from parts of LA into the Mid-South. Weak low-topped convection (with localized gusty winds) will be possible into the Ohio Valley, but increasingly negligible buoyancy is expected to limit thunderstorm potential with northward extent. ..Dean.. 11/24/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CST Sun Nov 24 2024 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible Monday into Monday night from Louisiana into parts of the Mid-South, and also near the Oregon and northern California coasts. ...Synopsis... A strong mid/upper-level shortwave trough is forecast to take on a negative tilt on Monday, as it moves quickly eastward across parts of the Midwest and Ohio Valley. An associated surface low is forecast to move from IL toward lower MI through the day and evening, as a trailing cold front moves through parts of the Great Lakes, Ohio/Tennessee Valleys, and the mid/lower Mississippi Valley. Isolated thunderstorms may develop later Monday near the front from parts of LA into the Mid-South. Farther west, a mid/upper-level trough and embedded midlevel low are forecast are forecast to move eastward across parts of the Pacific Northwest, northern CA, and the Great Basin. Weak convection with isolated lightning flashes will be possible near the OR and northern CA coasts, in association with this trough. ...Parts of LA into the TN/OH Valleys... Low-level moisture return along/ahead of the cold front will result in 60s F dewpoints reaching as far north as the Mid-South by Monday afternoon, with 50s F dewpoints extending into parts of the Ohio Valley. Stronger large-scale ascent associated with the shortwave trough will be displaced to the north of the richer low-level moisture, and buoyancy is expected to generally remain weak. As a result, organized deep convection is currently not anticipated, despite the presence of favorable deep-layer shear. Generally weak convection with isolated thunderstorm potential will be possible (primarily later in the forecast period) in the vicinity of the front from parts of LA into the Mid-South. Weak low-topped convection (with localized gusty winds) will be possible into the Ohio Valley, but increasingly negligible buoyancy is expected to limit thunderstorm potential with northward extent. ..Dean.. 11/24/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1058 AM CST Sun Nov 24 2024 Valid 241700Z - 251200Z ...NO CRITICAL AREAS... ...17z Update... No changes were made to the current valid outlook. Localized elevated fire-weather conditions are possible across parts of the southern High Plains. However, area fuels remain largely unreceptive to fire spread given recent precipitation and cooler temperatures. See the prior discussion for more info. ..Lyons.. 11/24/2024 .PREV DISCUSSION... /ISSUED 0129 AM CST Sun Nov 24 2024/ ...Synopsis... A mid-level trough will move through the Northern Plains today, and as it does, the attendant surface low will also move east -- from the central Plains into the mid-Mississippi Valley. The cyclonic flow around this surface low will help drive a surface cold front south and east through the Southern Plains. The flow behind this front will be a dry, downslope flow that will support at least a few hours of elevated to locally critical fire weather conditions. However, recent rains have left fuel moisture sufficiently high that fire weather highlights are not warranted. ...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 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1004 AM CST Sun Nov 24 2024 Valid 241630Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Pacific Northwest... Recent water vapor imagery shows persistent onshore flow regime along the Pacific Northwest coast, with several small vorticity maxima embedded in the flow. Several pockets of lightning have been noted with this offshore activity, but the trend has been for rapid dissipation of lightning as activity moved ashore. This trend should continue through the day, with the risk of thunderstorms primarily focused along the coast of southwest OR and northwest CA. ..Hart/Supinie.. 11/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0631 AM CST Sun Nov 24 2024 Valid 241300Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, a belt of relatively strong flow will bend cyclonically from CA to the central Great Plains, changing curvature through a low-amplitude, eastward moving synoptic ridge over the Upper Great Lakes and Ohio Valley, then cyclonically again across the Mid-Atlantic and New England. A long-lasting, deeply occluded cyclone will move eastward from the Canadian Maritime Provinces through the period. Upstream, a smaller cyclone -- initially located over southern SK -- will move slowly eastward to southern MB by 12Z tomorrow, with trough southward over the Dakotas. However, too little moisture will be available for a general thunderstorm outlook. Farther west, a synoptic-scale cyclone offshore from the Olympic Peninsula and Vancouver Island will pivot slowly southward then eastward through tonight, but will remain over Pacific waters. Intervening ridging should remain over the northern Rockies and vicinity. However, cold air aloft and steep low/middle-level lapse rates will overlie a moist marine layer, supporting isolated to widely scattered, episodic thunder mainly offshore. Some of this activity may move inland before dissipating in more-stable low-level conditions. A shortwave trough -- evident in moisture-channel imagery south and east of the ridge from the Yellowstone region across the northern Great Basin to central CA -- is forecast to move quickly eastward across the central Rockies and central Plains through the period, phasing with the SK/MB low by 12Z tomorrow. The associated cold front was drawn at 11Z today across an area of low pressure extending from northeastern NE to southwestern KS, then arching over southeastern CO. A warm front was drawn over southeastern KS and southwestern MO, with a secondary warm front over southern IA and northern IL. The low should consolidate today across northeastern KS into northern MO, and move to near the southwestern shore of Lake Michigan by the end of the period, when the cold front reaches to near a line from BMI-STL-FSM-SPS-HOB. Scattered elevated showers are possible late tonight near and north of the warm front, across parts of northeastern IL, WI, Lower MI, IN, and OH. However, the warm conveyor will lack rich moisture, and forecast soundings reasonably suggest buoyancy will be too shallow and strongly capped for an areal thunderstorm threat. ..Edwards/Leitman.. 11/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0631 AM CST Sun Nov 24 2024 Valid 241300Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, a belt of relatively strong flow will bend cyclonically from CA to the central Great Plains, changing curvature through a low-amplitude, eastward moving synoptic ridge over the Upper Great Lakes and Ohio Valley, then cyclonically again across the Mid-Atlantic and New England. A long-lasting, deeply occluded cyclone will move eastward from the Canadian Maritime Provinces through the period. Upstream, a smaller cyclone -- initially located over southern SK -- will move slowly eastward to southern MB by 12Z tomorrow, with trough southward over the Dakotas. However, too little moisture will be available for a general thunderstorm outlook. Farther west, a synoptic-scale cyclone offshore from the Olympic Peninsula and Vancouver Island will pivot slowly southward then eastward through tonight, but will remain over Pacific waters. Intervening ridging should remain over the northern Rockies and vicinity. However, cold air aloft and steep low/middle-level lapse rates will overlie a moist marine layer, supporting isolated to widely scattered, episodic thunder mainly offshore. Some of this activity may move inland before dissipating in more-stable low-level conditions. A shortwave trough -- evident in moisture-channel imagery south and east of the ridge from the Yellowstone region across the northern Great Basin to central CA -- is forecast to move quickly eastward across the central Rockies and central Plains through the period, phasing with the SK/MB low by 12Z tomorrow. The associated cold front was drawn at 11Z today across an area of low pressure extending from northeastern NE to southwestern KS, then arching over southeastern CO. A warm front was drawn over southeastern KS and southwestern MO, with a secondary warm front over southern IA and northern IL. The low should consolidate today across northeastern KS into northern MO, and move to near the southwestern shore of Lake Michigan by the end of the period, when the cold front reaches to near a line from BMI-STL-FSM-SPS-HOB. Scattered elevated showers are possible late tonight near and north of the warm front, across parts of northeastern IL, WI, Lower MI, IN, and OH. However, the warm conveyor will lack rich moisture, and forecast soundings reasonably suggest buoyancy will be too shallow and strongly capped for an areal thunderstorm threat. ..Edwards/Leitman.. 11/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0631 AM CST Sun Nov 24 2024 Valid 241300Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, a belt of relatively strong flow will bend cyclonically from CA to the central Great Plains, changing curvature through a low-amplitude, eastward moving synoptic ridge over the Upper Great Lakes and Ohio Valley, then cyclonically again across the Mid-Atlantic and New England. A long-lasting, deeply occluded cyclone will move eastward from the Canadian Maritime Provinces through the period. Upstream, a smaller cyclone -- initially located over southern SK -- will move slowly eastward to southern MB by 12Z tomorrow, with trough southward over the Dakotas. However, too little moisture will be available for a general thunderstorm outlook. Farther west, a synoptic-scale cyclone offshore from the Olympic Peninsula and Vancouver Island will pivot slowly southward then eastward through tonight, but will remain over Pacific waters. Intervening ridging should remain over the northern Rockies and vicinity. However, cold air aloft and steep low/middle-level lapse rates will overlie a moist marine layer, supporting isolated to widely scattered, episodic thunder mainly offshore. Some of this activity may move inland before dissipating in more-stable low-level conditions. A shortwave trough -- evident in moisture-channel imagery south and east of the ridge from the Yellowstone region across the northern Great Basin to central CA -- is forecast to move quickly eastward across the central Rockies and central Plains through the period, phasing with the SK/MB low by 12Z tomorrow. The associated cold front was drawn at 11Z today across an area of low pressure extending from northeastern NE to southwestern KS, then arching over southeastern CO. A warm front was drawn over southeastern KS and southwestern MO, with a secondary warm front over southern IA and northern IL. The low should consolidate today across northeastern KS into northern MO, and move to near the southwestern shore of Lake Michigan by the end of the period, when the cold front reaches to near a line from BMI-STL-FSM-SPS-HOB. Scattered elevated showers are possible late tonight near and north of the warm front, across parts of northeastern IL, WI, Lower MI, IN, and OH. However, the warm conveyor will lack rich moisture, and forecast soundings reasonably suggest buoyancy will be too shallow and strongly capped for an areal thunderstorm threat. ..Edwards/Leitman.. 11/24/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0631 AM CST Sun Nov 24 2024 Valid 241300Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, a belt of relatively strong flow will bend cyclonically from CA to the central Great Plains, changing curvature through a low-amplitude, eastward moving synoptic ridge over the Upper Great Lakes and Ohio Valley, then cyclonically again across the Mid-Atlantic and New England. A long-lasting, deeply occluded cyclone will move eastward from the Canadian Maritime Provinces through the period. Upstream, a smaller cyclone -- initially located over southern SK -- will move slowly eastward to southern MB by 12Z tomorrow, with trough southward over the Dakotas. However, too little moisture will be available for a general thunderstorm outlook. Farther west, a synoptic-scale cyclone offshore from the Olympic Peninsula and Vancouver Island will pivot slowly southward then eastward through tonight, but will remain over Pacific waters. Intervening ridging should remain over the northern Rockies and vicinity. However, cold air aloft and steep low/middle-level lapse rates will overlie a moist marine layer, supporting isolated to widely scattered, episodic thunder mainly offshore. Some of this activity may move inland before dissipating in more-stable low-level conditions. A shortwave trough -- evident in moisture-channel imagery south and east of the ridge from the Yellowstone region across the northern Great Basin to central CA -- is forecast to move quickly eastward across the central Rockies and central Plains through the period, phasing with the SK/MB low by 12Z tomorrow. The associated cold front was drawn at 11Z today across an area of low pressure extending from northeastern NE to southwestern KS, then arching over southeastern CO. A warm front was drawn over southeastern KS and southwestern MO, with a secondary warm front over southern IA and northern IL. The low should consolidate today across northeastern KS into northern MO, and move to near the southwestern shore of Lake Michigan by the end of the period, when the cold front reaches to near a line from BMI-STL-FSM-SPS-HOB. Scattered elevated showers are possible late tonight near and north of the warm front, across parts of northeastern IL, WI, Lower MI, IN, and OH. However, the warm conveyor will lack rich moisture, and forecast soundings reasonably suggest buoyancy will be too shallow and strongly capped for an areal thunderstorm threat. ..Edwards/Leitman.. 11/24/2024 Read more