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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Tue Sep 10 2024 Valid 102000Z - 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. ...20z Update... The forecast remains on track and no changes are needed to the D1 Convective Outlook. See previous discussion below for more information. ..Thornton/Gleason.. 09/10/2024 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue Sep 10 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Tue Sep 10 2024 Valid 102000Z - 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. ...20z Update... The forecast remains on track and no changes are needed to the D1 Convective Outlook. See previous discussion below for more information. ..Thornton/Gleason.. 09/10/2024 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue Sep 10 2024/ ...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. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0213 PM CDT Tue Sep 10 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN DAKOTAS... ...SUMMARY... A low-probability tornado threat may persist into Thursday across parts of the Deep South. Isolated large hail and severe gusts will be possible over the northern High Plains vicinity on Thursday afternoon and evening. ...Synopsis... An upper trough over the Great Basin will eject northeastward into the northern Rockies/High Plains through Friday morning, with moderate midlevel meridional flow aloft. Accompanying this trough will be a cold front which will extend from eastern MT into eastern WY. To the east, TC Francine is forecast to move northward up the lower MS valley, with strong southerly winds helping to bring moisture north across much of the Southeast east of the center/low. High pressure will remain over the Mid Atlantic, adding to the pressure gradient east of the cyclone. ...Eastern MT into the western Dakotas... Daytime heating as well as cooling aloft with the upper trough will result in steepening lapse rates, though low-level moisture will be meager with 40s dewpoints primarily east of the cold front. A narrow band of uncapped and unstable air will still develop during the late afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer effective shear. As such, scattered cells are likely to develop along the front, and the elongated hodographs may favor a few single cells despite linear forcing mechanism. Therefore isolated hail over 1.00" may occur, as well as brief bowing segments producing strong gusts. ...Much of AL, eastern MS...FL Panhandle... Scattered thunderstorms are likely to exist from the northeastern quadrant of TC Francine arcing southeastward across much of AL and into the FL Panhandle Thursday morning. Low-level theta-e advection will exist near a warm front as it lifts north across AL, though dry air will exist from the Appalachians into parts of the OH/TN Valleys initially. The greatest risk of a couple tornadoes will likely be limited to storms within the instability plume centered over AL, and including the FL Panhandle and perhaps far eastern MS. Low-level shear will be strong to start the day, but will be reduced as the system continues north and low-level flow veers. ..Jewell.. 09/10/2024 Read more

Drought in Ohio has led to the early harvest of withered crops was wiping out hay and feed reserves intended to be fed to livestock through the winter. Hundreds of worried farmers have contacted the Ohio Farm Bureau about keeping their animals fed through the winter. Because some springs have gone dry, some farmers were hauling water for their livestock. Precipitation was ample in April, but has been below normal since then, making it a challenge to grow crops. Corn that would normally be harvested at the end of September was already being harvested. The past four dry months have stressed crops to the extent that they stopped growing and instead developed their seed so the plant could germinate in the spring. An early harvest means that yields will be lower than desired. Zanesville Times Recorder (Ohio), Sept 10, 2024

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Sep 10 2024 Valid 111200Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR A LARGE PORTION OF THE GREAT BASIN... Minor modifications to the critical area have been made on account of recent guidance. The remainder of the forecast remains on track. See the previous discussion for greater details. ..Wendt.. 09/10/2024 .PREV DISCUSSION... /ISSUED 0202 AM CDT Tue Sep 10 2024/ ...Synopsis... The upper trough over the western US will quickly intensify Wednesday, as a shortwave perturbation and mid-level jet streak move onshore over the West Coast. As the trough strengthens, mid-level flow over much of the West will increase. A surface low will deepen over the northern Great Basin, while a cold front moves onshore and also strengthens. To the east, TS Francine will approach the Gulf Coast with offshore winds likely over parts of the mid South. Strong surface winds, low humidity, and thunderstorms over parts of the West and central US will support critical fire-weather concerns Wednesday. ...Great Basin... Ahead of the deepening trough, a potent mid-level jet streak will move over parts of the western Great Basin beginning early Wednesday. A deepening surface low in parts of the eastern Basin will drive 20-25 mph winds over much of NV into western UT. Augmented by downslope flow off the Sierra and the approaching cold front, a brief period of winds of 25-30 mph will be possible along with RH below 15%. Widespread critical fire-weather conditions are likely over parts of the Great Basin. Fire-weather concerns should diminish behind the front as cooler and more quiescent conditions are expected behind the front into early Thursday. ...Lee of the Rockies and High Plains... As the trough approaches, height falls and stronger flow aloft will overspread the Rockies and High Plains. A surface low will deepen first in eastern MT, with a lee trough extending south into the central High Plains. Near the lee trough, strong southerly winds will overlap with areas of low RH and drying fine fuels. Elevated fire weather concerns are expected over parts of the High Plains Wednesday afternoon and evening. ...Mid South... As Francine approaches the Gulf Coast Wednesday and Wednesday night, offshore pressure gradients will increase over parts of the lower MS Valley and Mid South. While humidity values are not expected to be overly low with the tropical air mass approaching, strong gusts are expected to overlap with areas of relatively dry fuels and little recent rainfall. Brief elevated fire-weather conditions are possible before rain chances increase into early Thursday. ...Northwest Thunder... Ahead of the cold front, increasing mid-level moisture and strong lift from the trough will promote scattered thunderstorms Wednesday afternoon. Lightning may interact with areas of somewhat drier fuels over parts of the Northwest and northern Rockies before broader wetting rainfall develops. However, these storms will likely have higher precipitation efficiency with a cooler air mass and more plentiful Pacific moisture in place. This lends significant uncertainty on the threat for any lightning ignitions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 101740
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Sep 10 2024

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

Offshore of Southwestern Mexico:
A broad area of low pressure is developing a couple hundred miles
to the south-southwest of the coast of southwestern Mexico.
Environmental conditions are forecast to be conducive for some
gradual development of this system, and a tropical depression could
form during the latter part of the week while it moves generally
north-northwestward, near the coast of southwestern Mexico and
towards the Baja California Peninsula.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...medium...60 percent.

$$
Forecaster Papin

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