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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1219 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN PARTS OF THE CENTRAL GULF COAST STATES... ...SUMMARY... A few tornadoes are possible across the central Gulf Coast vicinity on Wednesday into Wednesday night, in association with Tropical Cyclone Francine. ...Northern Gulf Coast... Francine is forecast to become a hurricane over the northwest Gulf of Mexico, with strengthening wind fields overspreading much of the central Gulf Coast states from Wednesday afternoon into the night. Preceding this system, a stationary front will exist roughly parallel to the coast, with the more unstable/tropical moisture to the south. As southerly winds increase east of the cyclone center, this will lift the front north as a warm front, with mid 70s F dewpoints spreading north across southern MS, AL, and the western FL Panhandle. Rapidly enlarging hodographs in the vicinity of the warm front may support a zone of tornado potential as bands of cells push northward off the Gulf of Mexico and arc northwestward. Tornado potential on the north side will be limited by the more stable air due to high pressure to the north. ...Parts of the Northwest/Northern Rockies... A strong shortwave trough will move across the Pacific Northwest and into the Great Basin, with substantial cooling aloft. A cold front will generally stretch from a low over western MT across central ID and into northern NV during the afternoon, with the strongest heating ahead of the front across NV, UT and western WY. Post frontal rain and a few thunderstorms are likely near the developing cold front early in the day from northern ID into eastern OR, with diurnal convection developing over southeast OR, southwest ID and northern NV. Deep-layer shear will not be particularly strong given that the primary speed max will dive southeastward across the Sierra. However, cool temperatures aloft may yield small hail, with scattered strong gusts with the larger clusters of storms. Additional marginally severe storms may occur from western MT into northwest WY near the deepening surface trough and aided by very steep lapse rates supporting strong gusts. ..Jewell.. 09/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1219 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN PARTS OF THE CENTRAL GULF COAST STATES... ...SUMMARY... A few tornadoes are possible across the central Gulf Coast vicinity on Wednesday into Wednesday night, in association with Tropical Cyclone Francine. ...Northern Gulf Coast... Francine is forecast to become a hurricane over the northwest Gulf of Mexico, with strengthening wind fields overspreading much of the central Gulf Coast states from Wednesday afternoon into the night. Preceding this system, a stationary front will exist roughly parallel to the coast, with the more unstable/tropical moisture to the south. As southerly winds increase east of the cyclone center, this will lift the front north as a warm front, with mid 70s F dewpoints spreading north across southern MS, AL, and the western FL Panhandle. Rapidly enlarging hodographs in the vicinity of the warm front may support a zone of tornado potential as bands of cells push northward off the Gulf of Mexico and arc northwestward. Tornado potential on the north side will be limited by the more stable air due to high pressure to the north. ...Parts of the Northwest/Northern Rockies... A strong shortwave trough will move across the Pacific Northwest and into the Great Basin, with substantial cooling aloft. A cold front will generally stretch from a low over western MT across central ID and into northern NV during the afternoon, with the strongest heating ahead of the front across NV, UT and western WY. Post frontal rain and a few thunderstorms are likely near the developing cold front early in the day from northern ID into eastern OR, with diurnal convection developing over southeast OR, southwest ID and northern NV. Deep-layer shear will not be particularly strong given that the primary speed max will dive southeastward across the Sierra. However, cool temperatures aloft may yield small hail, with scattered strong gusts with the larger clusters of storms. Additional marginally severe storms may occur from western MT into northwest WY near the deepening surface trough and aided by very steep lapse rates supporting strong gusts. ..Jewell.. 09/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1219 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN PARTS OF THE CENTRAL GULF COAST STATES... ...SUMMARY... A few tornadoes are possible across the central Gulf Coast vicinity on Wednesday into Wednesday night, in association with Tropical Cyclone Francine. ...Northern Gulf Coast... Francine is forecast to become a hurricane over the northwest Gulf of Mexico, with strengthening wind fields overspreading much of the central Gulf Coast states from Wednesday afternoon into the night. Preceding this system, a stationary front will exist roughly parallel to the coast, with the more unstable/tropical moisture to the south. As southerly winds increase east of the cyclone center, this will lift the front north as a warm front, with mid 70s F dewpoints spreading north across southern MS, AL, and the western FL Panhandle. Rapidly enlarging hodographs in the vicinity of the warm front may support a zone of tornado potential as bands of cells push northward off the Gulf of Mexico and arc northwestward. Tornado potential on the north side will be limited by the more stable air due to high pressure to the north. ...Parts of the Northwest/Northern Rockies... A strong shortwave trough will move across the Pacific Northwest and into the Great Basin, with substantial cooling aloft. A cold front will generally stretch from a low over western MT across central ID and into northern NV during the afternoon, with the strongest heating ahead of the front across NV, UT and western WY. Post frontal rain and a few thunderstorms are likely near the developing cold front early in the day from northern ID into eastern OR, with diurnal convection developing over southeast OR, southwest ID and northern NV. Deep-layer shear will not be particularly strong given that the primary speed max will dive southeastward across the Sierra. However, cool temperatures aloft may yield small hail, with scattered strong gusts with the larger clusters of storms. Additional marginally severe storms may occur from western MT into northwest WY near the deepening surface trough and aided by very steep lapse rates supporting strong gusts. ..Jewell.. 09/10/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1219 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN PARTS OF THE CENTRAL GULF COAST STATES... ...SUMMARY... A few tornadoes are possible across the central Gulf Coast vicinity on Wednesday into Wednesday night, in association with Tropical Cyclone Francine. ...Northern Gulf Coast... Francine is forecast to become a hurricane over the northwest Gulf of Mexico, with strengthening wind fields overspreading much of the central Gulf Coast states from Wednesday afternoon into the night. Preceding this system, a stationary front will exist roughly parallel to the coast, with the more unstable/tropical moisture to the south. As southerly winds increase east of the cyclone center, this will lift the front north as a warm front, with mid 70s F dewpoints spreading north across southern MS, AL, and the western FL Panhandle. Rapidly enlarging hodographs in the vicinity of the warm front may support a zone of tornado potential as bands of cells push northward off the Gulf of Mexico and arc northwestward. Tornado potential on the north side will be limited by the more stable air due to high pressure to the north. ...Parts of the Northwest/Northern Rockies... A strong shortwave trough will move across the Pacific Northwest and into the Great Basin, with substantial cooling aloft. A cold front will generally stretch from a low over western MT across central ID and into northern NV during the afternoon, with the strongest heating ahead of the front across NV, UT and western WY. Post frontal rain and a few thunderstorms are likely near the developing cold front early in the day from northern ID into eastern OR, with diurnal convection developing over southeast OR, southwest ID and northern NV. Deep-layer shear will not be particularly strong given that the primary speed max will dive southeastward across the Sierra. However, cool temperatures aloft may yield small hail, with scattered strong gusts with the larger clusters of storms. Additional marginally severe storms may occur from western MT into northwest WY near the deepening surface trough and aided by very steep lapse rates supporting strong gusts. ..Jewell.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Tue Sep 10 2024 Valid 101630Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. ..Gleason/Bentley.. 09/10/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...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 1108 AM CDT Tue Sep 10 2024 Valid 101700Z - 111200Z No changes to the ongoing forecast. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Sep 10 2024/ ...Synopsis... Broad troughing over the Northwest will gradually intensify later today and tonight, as a stronger shortwave and mid-level jet approach from the eastern Pacific. Increasing flow aloft will move inland, supporting the potential for strong surface winds and low humidity over parts of the Northwest and Great Basin. Elevated to near-critical fire-weather conditions are likely. ...Great Basin... As the upper trough shifts east, mid-level flow should strengthen over parts of the western Great Basin. Gusty downslope winds are likely in the lee of the Sierra and across parts of southern NV and western UT. Surface winds of 15-25 mph should overlap with RH below 15%, and within areas of dry fuels this afternoon. Elevated to near-critical fire-weather conditions are likely across much of NV and into portions of northern CA, southern ID and far western UT. Confidence in the development of nearly to briefly critical meteorological conditions is highest over parts of southern NV where winds are expected to be slightly stronger. However, fuels here are also slightly less receptive, and the overlap of favorable wind/RH may also be briefer. Thus, confidence remains too low for critical highlights currently. ...Cascades and Columbia Gorge... Increasing mid-level winds will combine with a strong onshore pressure gradient behind the departing cold front to drive 15-20 mph winds through Cascade Gaps and into the western Columbia Basin. While cooler and more moderate, pockets of RH below 25% should overlap with the stronger winds. The duration of these breezy and somewhat dry conditions may be somewhat limited, but elevated to briefly critical fire weather conditions are possible within dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Tue Sep 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER COASTAL AREAS OF LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Synopsis... In mid/upper levels, a strong shortwave trough now over the eastern Gulf of Alaska is forecast to dig southeastward and develop a closed 500-mb cyclone tonight, with the low about 150 nm west of AST by 12Z tomorrow. Ahead of this progressive and intensifying perturbation, height falls and strengthening cyclonic flow will spread across the northwestern CONUS throughout the period, combining with modest low/ middle-level moisture to support thunderstorm potential in parts of the Northwest, in addition to the diurnal-cycle convection across the Four Corners region, central/northern Rockies and parts of MT. Downstream, mid/upper flow should be nearly zonal from the Rockies across the Great Lakes. An embedded shortwave trough was evident in moisture-channel imagery over the Dakotas. This feature is forecast to move eastward to MN by 00Z, then across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z. Farther south, a weak, cut-off, mid/upper-level low over north-central TX should drift erratically near its present location, while increasingly influencing the path of Tropical Storm Francine. The 11Z surface analysis showed a wavy, quasistationary frontal zone fro Atlantic waters offshore SC, across northern FL to near the Mississippi River mouth, then a warm front arching across Gulf waters just south of the LA and TX Coasts, and into western parts of the Francine circulation. This boundary should move little from about 90W eastward, but remain a warm front over the upper TX and LA coastal waters, diffusely shifting inland over southern LA through the period. ...LA Coast... T.S. Francine -- initially centered southeast of BRO -- is forecast by NHC to turn northeastward across the northwestern Gulf today and become a hurricane, then move ashore in Louisiana on day 2. Suitably rich low-level moisture already is in place over coastal LA, and scattered to numerous showers and thunderstorms should cover the outlook area throughout much of the period, even well northeast of Francine's center. However, supercell potential will await sufficiently strong wind fields reaching the coastline ahead of the cyclone to enlarge hodographs favorably -- likely during the last few hours of the period. Then, tornado potential will be a matter of having relatively distinct/discrete, outer-band convection that can survive long enough to mature into supercells before weakening again in more-stable inflow air -- either inland or in broader precip areas. Unconditional probabilities are kept at marginal levels for now, given the late timing of the favorable kinematic fields, the nocturnal min in overland instability, and convective/ structural uncertainties with Francine. ..Edwards/Kerr.. 09/10/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 AM CDT Tue Sep 10 2024 Valid 101300Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER COASTAL AREAS OF LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...Synopsis... In mid/upper levels, a strong shortwave trough now over the eastern Gulf of Alaska is forecast to dig southeastward and develop a closed 500-mb cyclone tonight, with the low about 150 nm west of AST by 12Z tomorrow. Ahead of this progressive and intensifying perturbation, height falls and strengthening cyclonic flow will spread across the northwestern CONUS throughout the period, combining with modest low/ middle-level moisture to support thunderstorm potential in parts of the Northwest, in addition to the diurnal-cycle convection across the Four Corners region, central/northern Rockies and parts of MT. Downstream, mid/upper flow should be nearly zonal from the Rockies across the Great Lakes. An embedded shortwave trough was evident in moisture-channel imagery over the Dakotas. This feature is forecast to move eastward to MN by 00Z, then across the Upper Great Lakes to Lake Huron and adjoining parts of ON by 12Z. Farther south, a weak, cut-off, mid/upper-level low over north-central TX should drift erratically near its present location, while increasingly influencing the path of Tropical Storm Francine. The 11Z surface analysis showed a wavy, quasistationary frontal zone fro Atlantic waters offshore SC, across northern FL to near the Mississippi River mouth, then a warm front arching across Gulf waters just south of the LA and TX Coasts, and into western parts of the Francine circulation. This boundary should move little from about 90W eastward, but remain a warm front over the upper TX and LA coastal waters, diffusely shifting inland over southern LA through the period. ...LA Coast... T.S. Francine -- initially centered southeast of BRO -- is forecast by NHC to turn northeastward across the northwestern Gulf today and become a hurricane, then move ashore in Louisiana on day 2. Suitably rich low-level moisture already is in place over coastal LA, and scattered to numerous showers and thunderstorms should cover the outlook area throughout much of the period, even well northeast of Francine's center. However, supercell potential will await sufficiently strong wind fields reaching the coastline ahead of the cyclone to enlarge hodographs favorably -- likely during the last few hours of the period. Then, tornado potential will be a matter of having relatively distinct/discrete, outer-band convection that can survive long enough to mature into supercells before weakening again in more-stable inflow air -- either inland or in broader precip areas. Unconditional probabilities are kept at marginal levels for now, given the late timing of the favorable kinematic fields, the nocturnal min in overland instability, and convective/ structural uncertainties with Francine. ..Edwards/Kerr.. 09/10/2024 Read more