Aggregator

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Fri Oct 04 2024 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Potential for severe storms appears low on Saturday. ...Upper Midwest into the Upper Great Lakes... Northern-stream shortwave trough is forecast to move quickly eastward from the Canadian Prairies and adjacent northern High Plains through western Ontario and the Upper Midwest on Saturday. This shortwave is expected to mature as it progresses eastward, with the resulting closed mid-level cyclone over northwestern Ontario by early Sunday morning. An associated surface low will accompany this system, moving eastward across the central portion of Canadian Prairie Provinces and ending the period stacked beneath the mid-level low over northwestern Ontario. Cold front attendant to this surface low will push eastward across the northern and central Plains through the Upper Midwest. By 12Z Sunday, this front will likely extend from central Lower MI southwestward through central MO before then turning more westward and extending along the OK/KS border vicinity. Warm-air advection will gradually increase within the warm sector ahead of the front throughout the period. Low to mid-level moistening from this warm-air advection coupled with cooling mid-level temperatures will result in elevated buoyancy across the Upper Midwest and Upper Great Lakes from Saturday evening into Sunday morning. Isolated thunderstorms are possible within this region as a result. Enhanced mid-level flow associated with the shortwave trough will spread into the region during the evening as well, supporting moderate to strong deep-layer vertical shear. However, the cloud-bearing layer shear values will be more modest (i.e. around half of the bulk shear values), and the resulting combination of modest buoyancy and shear will likely result in predominantly sub-severe thunderstorms. ...Gulf Coast... Showers and thunderstorms are expected across the Gulf Coast and FL Peninsula throughout the period as low-level easterlies persist within a very moist airmass. Limited buoyancy and weak shear should keep the severe-thunderstorm potential low. ..Mosier.. 10/04/2024 Read more

000
ABPZ20 KNHC 040507
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Thu Oct 3 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Western Portion of the East Pacific (EP98):
A low pressure system located well to the west-southwest of the
southern tip of the Baja California peninsula continues to produce
disorganized shower and thunderstorm activity. Some limited
development is possible on Friday while the low moves slowly
northward or north-northeastward, but atmospheric conditions should
become less conducive and prevent further development by the
weekend.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...10 percent.

Offshore of Southwestern Mexico:
An area of low pressure could form off the coast of southwestern
Mexico during the early to middle part of next week. Thereafter,
some slow development is possible while the system drifts
northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Berg

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1133 PM CDT Thu Oct 03 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today through tonight. ...Discussion... Seasonably high moisture content will generally remain confined to where the low-level easterlies prevail, across the southwestern Atlantic through the Gulf Basin during this period. The boundary layer does remain relatively moist across much of the southeastern U.S., but this region, and most areas east of the Mississippi Valley, are forecast to remain under the influence of surface high pressure. Still, weak to modest destabilization and orographic forcing with daytime heating may contribute to some thunderstorm development today across parts of the upper Tennessee Valley and Cumberland Plateau into the Blue Ridge. Otherwise, higher thunderstorm probabilities likely will remain focused across southern portions of the Florida Peninsula and immediate northwestern through north central Gulf coastal areas. An area of thunderstorm development, largely aided by ascent associated with lower/mid-tropospheric warm advection, may be ongoing at 12Z this morning across parts of southeastern Iowa and adjacent northeastern Missouri/west central Illinois. But this appears likely to gradually diminish while slowly spreading southeastward across west central/central Illinois through mid to late morning. The stronger westerlies remain confined to the northern mid-latitudes, with one rather vigorous embedded short wave trough forecast to rapidly accelerate inland of the Pacific Northwest coast and across the northern Rockies by 12Z Saturday. Models indicate that this will be accompanied by cyclogenesis to the lee of the Canadian Rockies, and strong pre- and post-frontal lower/mid-tropospheric wind fields across the northern U.S. Rockies into Great Plains. Despite rather dry initial conditions, strong mid/upper forcing for ascent may contribute to at least weak high-based convection, near or above/to the cool side of the surging cold front. While it is possible that this could coincide with strong/gusty surface conditions, forecast soundings suggest minimal potential for these gusts to be related to moist convective processes, and it still appears unlikely that this convection will be accompanied by much, if any, lightning. ..Kerr/Squitieri.. 10/04/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Oct 03 2024 Valid 040100Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA...ADJACENT NORTHEASTERN MISSOURI AND WEST CENTRAL ILLINOIS... ...SUMMARY... An area of developing thunderstorms overnight may pose a risk for small to marginally severe hail across parts of southeastern Iowa, adjacent northeastern Missouri and west central Illinois. ...01Z Update... Within the mid-latitude westerlies, one notable short wave trough is forecast to continue digging across the northern Great Plains Red River Valley toward the upper Great Lakes region tonight. The southern periphery of the surrounding cyclonic mid/upper-level flow currently curves across southern Nebraska through the Missouri/Iowa border vicinity, where it is beginning to overspread an initially quasi-stationary frontal zone. Models suggest that this regime will become increasingly divergent late this evening into the overnight hours, contributing to increasing forcing for ascent. Lower/mid-level ascent is already increasing across Iowa and surrounding portions of the Missouri Valley/Upper Midwest, in response to warm advection. It appears that this will lead to increasing thunderstorm development by 05-07Z across parts of central/southern Iowa, where guidance indicates a corridor of modest destabilization is possible associated with weak elevated moisture return above the frontal zone. Forecast soundings indicate most unstable CAPE may increase in excess of 1000 J/kg along this corridor, in the presence of modest potential cloud-bearing layer shear. Thermodynamic profiles may include sufficiently cool mid-levels (and steep lapse rates) to support a risk for marginally severe hail (up to around 1 inch or so in diameter) in a few of the stronger storms. ..Kerr.. 10/04/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Oct 03 2024 Valid 040100Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA...ADJACENT NORTHEASTERN MISSOURI AND WEST CENTRAL ILLINOIS... ...SUMMARY... An area of developing thunderstorms overnight may pose a risk for small to marginally severe hail across parts of southeastern Iowa, adjacent northeastern Missouri and west central Illinois. ...01Z Update... Within the mid-latitude westerlies, one notable short wave trough is forecast to continue digging across the northern Great Plains Red River Valley toward the upper Great Lakes region tonight. The southern periphery of the surrounding cyclonic mid/upper-level flow currently curves across southern Nebraska through the Missouri/Iowa border vicinity, where it is beginning to overspread an initially quasi-stationary frontal zone. Models suggest that this regime will become increasingly divergent late this evening into the overnight hours, contributing to increasing forcing for ascent. Lower/mid-level ascent is already increasing across Iowa and surrounding portions of the Missouri Valley/Upper Midwest, in response to warm advection. It appears that this will lead to increasing thunderstorm development by 05-07Z across parts of central/southern Iowa, where guidance indicates a corridor of modest destabilization is possible associated with weak elevated moisture return above the frontal zone. Forecast soundings indicate most unstable CAPE may increase in excess of 1000 J/kg along this corridor, in the presence of modest potential cloud-bearing layer shear. Thermodynamic profiles may include sufficiently cool mid-levels (and steep lapse rates) to support a risk for marginally severe hail (up to around 1 inch or so in diameter) in a few of the stronger storms. ..Kerr.. 10/04/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0749 PM CDT Thu Oct 03 2024 Valid 040100Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS PARTS OF SOUTHEASTERN IOWA...ADJACENT NORTHEASTERN MISSOURI AND WEST CENTRAL ILLINOIS... ...SUMMARY... An area of developing thunderstorms overnight may pose a risk for small to marginally severe hail across parts of southeastern Iowa, adjacent northeastern Missouri and west central Illinois. ...01Z Update... Within the mid-latitude westerlies, one notable short wave trough is forecast to continue digging across the northern Great Plains Red River Valley toward the upper Great Lakes region tonight. The southern periphery of the surrounding cyclonic mid/upper-level flow currently curves across southern Nebraska through the Missouri/Iowa border vicinity, where it is beginning to overspread an initially quasi-stationary frontal zone. Models suggest that this regime will become increasingly divergent late this evening into the overnight hours, contributing to increasing forcing for ascent. Lower/mid-level ascent is already increasing across Iowa and surrounding portions of the Missouri Valley/Upper Midwest, in response to warm advection. It appears that this will lead to increasing thunderstorm development by 05-07Z across parts of central/southern Iowa, where guidance indicates a corridor of modest destabilization is possible associated with weak elevated moisture return above the frontal zone. Forecast soundings indicate most unstable CAPE may increase in excess of 1000 J/kg along this corridor, in the presence of modest potential cloud-bearing layer shear. Thermodynamic profiles may include sufficiently cool mid-levels (and steep lapse rates) to support a risk for marginally severe hail (up to around 1 inch or so in diameter) in a few of the stronger storms. ..Kerr.. 10/04/2024 Read more