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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0347 PM CDT Sun Sep 08 2024 Valid 101200Z - 161200Z A broad upper ridge will remain across the middle portions of the U.S. through the early parts of this week. Another strong upper trough will begin to approach the Northwest. By midweek, the trough will impact the Great Basin before lifting northeast into the northern Plains by the weekend. Another amplified trough may impact the western U.S. by next weekend, but confidence in the upper air pattern this far in advance is still low. ...Great Basin... Fire weather concerns will increase on Tuesday with the approach of the strong trough. An initially weak surface pattern will lead to less widespread winds of 15-20 mph (locally higher). Areas of northwest and southern Nevada and nearby vicinity appear most likely to observe several hours of elevated conditions. Greater fire weather concerns will develop on Wednesday as the trough moves into the western Basin by late afternoon. Widespread 15-25 mph winds appear probable. With the mid-level jet nosing into northern Sierra by late afternoon, some intense wind gusts could occur in the lee of the terrain of northwest Nevada for at least a brief period. Another corridor of strong wind is expected from southern Nevada into western Utah just ahead of the front. ...Northern/Central Plains... As the trough approaches, deepening surface cyclones on Wednesday and Thursday will drive strong surface winds across parts of the Plains. With preceding days of dry weather and the upper ridge driving above average temperatures, fine fuels should continue to dry and available ERC data suggest some areas will again approach the 90th percentile. As winds shift to southerly, it will take time to advect moisture northward. Furthermore, the tropical system in the Gulf will likely slow moisture return as offshore flow develops along its western flank. That said, the drier solutions have been given more weight this forecast even though signals for critical fire weather are weaker in the ECMWF and available ensembles. The strongest winds over the broadest area will likely occur on Thursday. Some signal for convection in the surface trough on Wednesday is noted, but amounts should remain isolated and minimal. ...Columbia Gorge... There is potential for elevated to briefly critical fire weather to occur on Tuesday. Increasing mid-level winds will combine with a strong onshore pressure gradient to drive 15-20 mph winds through the Gorge along with RH potentially near 15%. The duration of these conditions may be brief enough that highlights will not be warranted. ..Wendt.. 09/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0347 PM CDT Sun Sep 08 2024 Valid 101200Z - 161200Z A broad upper ridge will remain across the middle portions of the U.S. through the early parts of this week. Another strong upper trough will begin to approach the Northwest. By midweek, the trough will impact the Great Basin before lifting northeast into the northern Plains by the weekend. Another amplified trough may impact the western U.S. by next weekend, but confidence in the upper air pattern this far in advance is still low. ...Great Basin... Fire weather concerns will increase on Tuesday with the approach of the strong trough. An initially weak surface pattern will lead to less widespread winds of 15-20 mph (locally higher). Areas of northwest and southern Nevada and nearby vicinity appear most likely to observe several hours of elevated conditions. Greater fire weather concerns will develop on Wednesday as the trough moves into the western Basin by late afternoon. Widespread 15-25 mph winds appear probable. With the mid-level jet nosing into northern Sierra by late afternoon, some intense wind gusts could occur in the lee of the terrain of northwest Nevada for at least a brief period. Another corridor of strong wind is expected from southern Nevada into western Utah just ahead of the front. ...Northern/Central Plains... As the trough approaches, deepening surface cyclones on Wednesday and Thursday will drive strong surface winds across parts of the Plains. With preceding days of dry weather and the upper ridge driving above average temperatures, fine fuels should continue to dry and available ERC data suggest some areas will again approach the 90th percentile. As winds shift to southerly, it will take time to advect moisture northward. Furthermore, the tropical system in the Gulf will likely slow moisture return as offshore flow develops along its western flank. That said, the drier solutions have been given more weight this forecast even though signals for critical fire weather are weaker in the ECMWF and available ensembles. The strongest winds over the broadest area will likely occur on Thursday. Some signal for convection in the surface trough on Wednesday is noted, but amounts should remain isolated and minimal. ...Columbia Gorge... There is potential for elevated to briefly critical fire weather to occur on Tuesday. Increasing mid-level winds will combine with a strong onshore pressure gradient to drive 15-20 mph winds through the Gorge along with RH potentially near 15%. The duration of these conditions may be brief enough that highlights will not be warranted. ..Wendt.. 09/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0347 PM CDT Sun Sep 08 2024 Valid 101200Z - 161200Z A broad upper ridge will remain across the middle portions of the U.S. through the early parts of this week. Another strong upper trough will begin to approach the Northwest. By midweek, the trough will impact the Great Basin before lifting northeast into the northern Plains by the weekend. Another amplified trough may impact the western U.S. by next weekend, but confidence in the upper air pattern this far in advance is still low. ...Great Basin... Fire weather concerns will increase on Tuesday with the approach of the strong trough. An initially weak surface pattern will lead to less widespread winds of 15-20 mph (locally higher). Areas of northwest and southern Nevada and nearby vicinity appear most likely to observe several hours of elevated conditions. Greater fire weather concerns will develop on Wednesday as the trough moves into the western Basin by late afternoon. Widespread 15-25 mph winds appear probable. With the mid-level jet nosing into northern Sierra by late afternoon, some intense wind gusts could occur in the lee of the terrain of northwest Nevada for at least a brief period. Another corridor of strong wind is expected from southern Nevada into western Utah just ahead of the front. ...Northern/Central Plains... As the trough approaches, deepening surface cyclones on Wednesday and Thursday will drive strong surface winds across parts of the Plains. With preceding days of dry weather and the upper ridge driving above average temperatures, fine fuels should continue to dry and available ERC data suggest some areas will again approach the 90th percentile. As winds shift to southerly, it will take time to advect moisture northward. Furthermore, the tropical system in the Gulf will likely slow moisture return as offshore flow develops along its western flank. That said, the drier solutions have been given more weight this forecast even though signals for critical fire weather are weaker in the ECMWF and available ensembles. The strongest winds over the broadest area will likely occur on Thursday. Some signal for convection in the surface trough on Wednesday is noted, but amounts should remain isolated and minimal. ...Columbia Gorge... There is potential for elevated to briefly critical fire weather to occur on Tuesday. Increasing mid-level winds will combine with a strong onshore pressure gradient to drive 15-20 mph winds through the Gorge along with RH potentially near 15%. The duration of these conditions may be brief enough that highlights will not be warranted. ..Wendt.. 09/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ..Weinman.. 09/08/2024 .PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ...Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ..Weinman.. 09/08/2024 .PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ...Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ..Weinman.. 09/08/2024 .PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ...Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ..Weinman.. 09/08/2024 .PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ...Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sun Sep 08 2024 Valid 082000Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...20Z Update... The forecast remains on track, and no changes/additions were needed to the outlook with this update. In addition to the low-end/ localized convective concerns described below, a couple dry microbursts could accompany high-based thunderstorms developing over the higher terrain in portions of Southern CA this afternoon. While weak deep-layer flow/shear will limit thunderstorm organization/longevity here, a hot/deeply mixed boundary layer (temperatures around 100 F), and lower/middle 50s F dewpoints will still favor a few robust (albeit short-lived) storms capable of locally strong gusts. ..Weinman.. 09/08/2024 .PREV DISCUSSION... /ISSUED 1116 AM CDT Sun Sep 08 2024/ ...Synopsis and Discussion... Recent surface observations show a nearly stalled front over north FL. Daytime heating of a moist low-level airmass south of this boundary will likely encourage the development of scattered to numerous thunderstorms this afternoon over the northern and central FL Peninsula. While occasional strong/gusty winds may occur with any downdrafts, the presence of poor mid-level lapse rates should hinder updraft acceleration and overall convective intensity. Even with upper ridging remaining prominent over much of the West, high-based convection may develop this afternoon over the southern/central Rockies, and perhaps into the adjacent High Plains along/near a weak lee surface trough. Limited low-level moisture and generally weak effective bulk shear over these regions will likely preclude an organized severe threat, although strong winds may occur with any convection that can be sustained. Water vapor satellite imagery shows a mid-level shortwave trough over the Pacific Northwest this morning. This feature will move generally east-northeastward towards the northern Rockies through the period. Isolated thunderstorms may occur across interior portions of the Northwest this afternoon ahead of the shortwave trough. But, rather modest low-level moisture (surface dewpoints generally in the 30s/40s F) should hinder the development of any more than weak instability. Along with only modestly enhanced mid-level flow, the limited instability is expected to keep any severe wind threat with convective downdrafts across eastern WA/OR into ID and northern NV/UT quite sparse. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Sep 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are expected to develop on Tuesday across the Gulf Coast region and from the Four Corners northward into the north-central U.S. No severe threat is expected across the U.S. Tuesday or Tuesday night. ...Synopsis... A broad mid-level trough will impinge on the northwestern U.S. as upper ridging prevails over much of the CONUS on Tuesday. Surface high pressure will promote cool and stable conditions from the Midwest to the East Coast, limiting thunderstorm potential. However, orographic lift over the higher terrain in the Interior West, as well as surface lee troughing in the central and northern Plains, will promote at least isolated thunderstorm development during the afternoon and early evening hours. Steep lapse rates will overspread the northern Plains and Upper MS Valley regions by afternoon, promoting at least moderate instability, though the lack of low-level moisture should limit severe potential. The heating of rich low-level moisture along the Gulf Coast will encourage scattered thunderstorm development. By Tuesday, a tropical storm is likely to develop to the southeast of the TX coastline (per latest NHC forecast). The probable track of this developing tropical storm suggests that the more organized convection should remain offshore through Tuesday, which should keep any severe threat to a minimum. ..Squitieri.. 09/08/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Sep 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are expected to develop on Tuesday across the Gulf Coast region and from the Four Corners northward into the north-central U.S. No severe threat is expected across the U.S. Tuesday or Tuesday night. ...Synopsis... A broad mid-level trough will impinge on the northwestern U.S. as upper ridging prevails over much of the CONUS on Tuesday. Surface high pressure will promote cool and stable conditions from the Midwest to the East Coast, limiting thunderstorm potential. However, orographic lift over the higher terrain in the Interior West, as well as surface lee troughing in the central and northern Plains, will promote at least isolated thunderstorm development during the afternoon and early evening hours. Steep lapse rates will overspread the northern Plains and Upper MS Valley regions by afternoon, promoting at least moderate instability, though the lack of low-level moisture should limit severe potential. The heating of rich low-level moisture along the Gulf Coast will encourage scattered thunderstorm development. By Tuesday, a tropical storm is likely to develop to the southeast of the TX coastline (per latest NHC forecast). The probable track of this developing tropical storm suggests that the more organized convection should remain offshore through Tuesday, which should keep any severe threat to a minimum. ..Squitieri.. 09/08/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Sep 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are expected to develop on Tuesday across the Gulf Coast region and from the Four Corners northward into the north-central U.S. No severe threat is expected across the U.S. Tuesday or Tuesday night. ...Synopsis... A broad mid-level trough will impinge on the northwestern U.S. as upper ridging prevails over much of the CONUS on Tuesday. Surface high pressure will promote cool and stable conditions from the Midwest to the East Coast, limiting thunderstorm potential. However, orographic lift over the higher terrain in the Interior West, as well as surface lee troughing in the central and northern Plains, will promote at least isolated thunderstorm development during the afternoon and early evening hours. Steep lapse rates will overspread the northern Plains and Upper MS Valley regions by afternoon, promoting at least moderate instability, though the lack of low-level moisture should limit severe potential. The heating of rich low-level moisture along the Gulf Coast will encourage scattered thunderstorm development. By Tuesday, a tropical storm is likely to develop to the southeast of the TX coastline (per latest NHC forecast). The probable track of this developing tropical storm suggests that the more organized convection should remain offshore through Tuesday, which should keep any severe threat to a minimum. ..Squitieri.. 09/08/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Sep 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are expected to develop on Tuesday across the Gulf Coast region and from the Four Corners northward into the north-central U.S. No severe threat is expected across the U.S. Tuesday or Tuesday night. ...Synopsis... A broad mid-level trough will impinge on the northwestern U.S. as upper ridging prevails over much of the CONUS on Tuesday. Surface high pressure will promote cool and stable conditions from the Midwest to the East Coast, limiting thunderstorm potential. However, orographic lift over the higher terrain in the Interior West, as well as surface lee troughing in the central and northern Plains, will promote at least isolated thunderstorm development during the afternoon and early evening hours. Steep lapse rates will overspread the northern Plains and Upper MS Valley regions by afternoon, promoting at least moderate instability, though the lack of low-level moisture should limit severe potential. The heating of rich low-level moisture along the Gulf Coast will encourage scattered thunderstorm development. By Tuesday, a tropical storm is likely to develop to the southeast of the TX coastline (per latest NHC forecast). The probable track of this developing tropical storm suggests that the more organized convection should remain offshore through Tuesday, which should keep any severe threat to a minimum. ..Squitieri.. 09/08/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0154 PM CDT Sun Sep 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are expected to develop on Tuesday across the Gulf Coast region and from the Four Corners northward into the north-central U.S. No severe threat is expected across the U.S. Tuesday or Tuesday night. ...Synopsis... A broad mid-level trough will impinge on the northwestern U.S. as upper ridging prevails over much of the CONUS on Tuesday. Surface high pressure will promote cool and stable conditions from the Midwest to the East Coast, limiting thunderstorm potential. However, orographic lift over the higher terrain in the Interior West, as well as surface lee troughing in the central and northern Plains, will promote at least isolated thunderstorm development during the afternoon and early evening hours. Steep lapse rates will overspread the northern Plains and Upper MS Valley regions by afternoon, promoting at least moderate instability, though the lack of low-level moisture should limit severe potential. The heating of rich low-level moisture along the Gulf Coast will encourage scattered thunderstorm development. By Tuesday, a tropical storm is likely to develop to the southeast of the TX coastline (per latest NHC forecast). The probable track of this developing tropical storm suggests that the more organized convection should remain offshore through Tuesday, which should keep any severe threat to a minimum. ..Squitieri.. 09/08/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0150 PM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Sun Sep 08 2024/ ...Synopsis... A prominent shortwave, embedded within broader troughing over the Pacific Northwest, is forecast to move quickly eastward over parts of the Northern Rockies Monday. At the same time, ridging over the West should continue to weaken as a belt of stronger southwesterly flow aloft develops from the northern Great Basin and into the northern Rockies. Increasing surface winds, and warm/dry conditions will support the potential for elevated fire-weather conditions. ...Northwest and Great Basin... As troughing settles over the West Coast, the mid-level flow will continue to strengthen across the Sierras and northern Great Basin. Surface winds of 15-25 mph appear likely as momentum from aloft mixes down to the surface. Downsloping and continued warm temperatures should keep the air mass quite dry with RH minimums of 15-20% likely. Several hours of widespread elevated to near-critical fire-weather conditions are likely from northern CA/NV into parts of southern ID and western WY. A few hours of elevated to near-critical conditions are possible in the lee of the Cascades as winds increase ahead of a cold front moving onshore Monday. RH may be on the marginal side, particularly with northward extent, as a cooler Pacific air mass move in. However, downslope winds of 15-25 mph and recent active fire behavior suggest some fire weather concerns will be possible. ...Northern Rockies... As the shortwave trough approaches the Rockies, westerly flow aloft should quickly increase. Downslope trajectories and intensifying lee troughing will strengthen surface winds to 15-20 MPH across parts of MT and WY. With hot temperatures and little recent rainfall persisting, afternoon RH values should remain quite low, generally below 20-25%. With increasing winds, receptive fuels, and persistent dry conditions, periods of elevated fire-weather conditions are likely over parts of the northern Rockies. ...Dry Thunder... Across parts of the eastern Great Basin and central Rockies, lingering monsoon moisture will likely support isolated to scattered thunderstorms Monday afternoon. A mixed mode of wet and dry storms is expected with PWATs of 0.7-1 inch, and increasing mid-level flow supporting faster storm speeds. While there is some potential for drier strikes, fuels across much of the area are less receptive and storms should generally cluster with time. This suggests any dry lightning potential will be limited. ...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 0150 PM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Sun Sep 08 2024/ ...Synopsis... A prominent shortwave, embedded within broader troughing over the Pacific Northwest, is forecast to move quickly eastward over parts of the Northern Rockies Monday. At the same time, ridging over the West should continue to weaken as a belt of stronger southwesterly flow aloft develops from the northern Great Basin and into the northern Rockies. Increasing surface winds, and warm/dry conditions will support the potential for elevated fire-weather conditions. ...Northwest and Great Basin... As troughing settles over the West Coast, the mid-level flow will continue to strengthen across the Sierras and northern Great Basin. Surface winds of 15-25 mph appear likely as momentum from aloft mixes down to the surface. Downsloping and continued warm temperatures should keep the air mass quite dry with RH minimums of 15-20% likely. Several hours of widespread elevated to near-critical fire-weather conditions are likely from northern CA/NV into parts of southern ID and western WY. A few hours of elevated to near-critical conditions are possible in the lee of the Cascades as winds increase ahead of a cold front moving onshore Monday. RH may be on the marginal side, particularly with northward extent, as a cooler Pacific air mass move in. However, downslope winds of 15-25 mph and recent active fire behavior suggest some fire weather concerns will be possible. ...Northern Rockies... As the shortwave trough approaches the Rockies, westerly flow aloft should quickly increase. Downslope trajectories and intensifying lee troughing will strengthen surface winds to 15-20 MPH across parts of MT and WY. With hot temperatures and little recent rainfall persisting, afternoon RH values should remain quite low, generally below 20-25%. With increasing winds, receptive fuels, and persistent dry conditions, periods of elevated fire-weather conditions are likely over parts of the northern Rockies. ...Dry Thunder... Across parts of the eastern Great Basin and central Rockies, lingering monsoon moisture will likely support isolated to scattered thunderstorms Monday afternoon. A mixed mode of wet and dry storms is expected with PWATs of 0.7-1 inch, and increasing mid-level flow supporting faster storm speeds. While there is some potential for drier strikes, fuels across much of the area are less receptive and storms should generally cluster with time. This suggests any dry lightning potential will be limited. ...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 0150 PM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Sun Sep 08 2024/ ...Synopsis... A prominent shortwave, embedded within broader troughing over the Pacific Northwest, is forecast to move quickly eastward over parts of the Northern Rockies Monday. At the same time, ridging over the West should continue to weaken as a belt of stronger southwesterly flow aloft develops from the northern Great Basin and into the northern Rockies. Increasing surface winds, and warm/dry conditions will support the potential for elevated fire-weather conditions. ...Northwest and Great Basin... As troughing settles over the West Coast, the mid-level flow will continue to strengthen across the Sierras and northern Great Basin. Surface winds of 15-25 mph appear likely as momentum from aloft mixes down to the surface. Downsloping and continued warm temperatures should keep the air mass quite dry with RH minimums of 15-20% likely. Several hours of widespread elevated to near-critical fire-weather conditions are likely from northern CA/NV into parts of southern ID and western WY. A few hours of elevated to near-critical conditions are possible in the lee of the Cascades as winds increase ahead of a cold front moving onshore Monday. RH may be on the marginal side, particularly with northward extent, as a cooler Pacific air mass move in. However, downslope winds of 15-25 mph and recent active fire behavior suggest some fire weather concerns will be possible. ...Northern Rockies... As the shortwave trough approaches the Rockies, westerly flow aloft should quickly increase. Downslope trajectories and intensifying lee troughing will strengthen surface winds to 15-20 MPH across parts of MT and WY. With hot temperatures and little recent rainfall persisting, afternoon RH values should remain quite low, generally below 20-25%. With increasing winds, receptive fuels, and persistent dry conditions, periods of elevated fire-weather conditions are likely over parts of the northern Rockies. ...Dry Thunder... Across parts of the eastern Great Basin and central Rockies, lingering monsoon moisture will likely support isolated to scattered thunderstorms Monday afternoon. A mixed mode of wet and dry storms is expected with PWATs of 0.7-1 inch, and increasing mid-level flow supporting faster storm speeds. While there is some potential for drier strikes, fuels across much of the area are less receptive and storms should generally cluster with time. This suggests any dry lightning potential will be limited. ...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 0150 PM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Sun Sep 08 2024/ ...Synopsis... A prominent shortwave, embedded within broader troughing over the Pacific Northwest, is forecast to move quickly eastward over parts of the Northern Rockies Monday. At the same time, ridging over the West should continue to weaken as a belt of stronger southwesterly flow aloft develops from the northern Great Basin and into the northern Rockies. Increasing surface winds, and warm/dry conditions will support the potential for elevated fire-weather conditions. ...Northwest and Great Basin... As troughing settles over the West Coast, the mid-level flow will continue to strengthen across the Sierras and northern Great Basin. Surface winds of 15-25 mph appear likely as momentum from aloft mixes down to the surface. Downsloping and continued warm temperatures should keep the air mass quite dry with RH minimums of 15-20% likely. Several hours of widespread elevated to near-critical fire-weather conditions are likely from northern CA/NV into parts of southern ID and western WY. A few hours of elevated to near-critical conditions are possible in the lee of the Cascades as winds increase ahead of a cold front moving onshore Monday. RH may be on the marginal side, particularly with northward extent, as a cooler Pacific air mass move in. However, downslope winds of 15-25 mph and recent active fire behavior suggest some fire weather concerns will be possible. ...Northern Rockies... As the shortwave trough approaches the Rockies, westerly flow aloft should quickly increase. Downslope trajectories and intensifying lee troughing will strengthen surface winds to 15-20 MPH across parts of MT and WY. With hot temperatures and little recent rainfall persisting, afternoon RH values should remain quite low, generally below 20-25%. With increasing winds, receptive fuels, and persistent dry conditions, periods of elevated fire-weather conditions are likely over parts of the northern Rockies. ...Dry Thunder... Across parts of the eastern Great Basin and central Rockies, lingering monsoon moisture will likely support isolated to scattered thunderstorms Monday afternoon. A mixed mode of wet and dry storms is expected with PWATs of 0.7-1 inch, and increasing mid-level flow supporting faster storm speeds. While there is some potential for drier strikes, fuels across much of the area are less receptive and storms should generally cluster with time. This suggests any dry lightning potential will be limited. ...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 0150 PM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Sun Sep 08 2024/ ...Synopsis... A prominent shortwave, embedded within broader troughing over the Pacific Northwest, is forecast to move quickly eastward over parts of the Northern Rockies Monday. At the same time, ridging over the West should continue to weaken as a belt of stronger southwesterly flow aloft develops from the northern Great Basin and into the northern Rockies. Increasing surface winds, and warm/dry conditions will support the potential for elevated fire-weather conditions. ...Northwest and Great Basin... As troughing settles over the West Coast, the mid-level flow will continue to strengthen across the Sierras and northern Great Basin. Surface winds of 15-25 mph appear likely as momentum from aloft mixes down to the surface. Downsloping and continued warm temperatures should keep the air mass quite dry with RH minimums of 15-20% likely. Several hours of widespread elevated to near-critical fire-weather conditions are likely from northern CA/NV into parts of southern ID and western WY. A few hours of elevated to near-critical conditions are possible in the lee of the Cascades as winds increase ahead of a cold front moving onshore Monday. RH may be on the marginal side, particularly with northward extent, as a cooler Pacific air mass move in. However, downslope winds of 15-25 mph and recent active fire behavior suggest some fire weather concerns will be possible. ...Northern Rockies... As the shortwave trough approaches the Rockies, westerly flow aloft should quickly increase. Downslope trajectories and intensifying lee troughing will strengthen surface winds to 15-20 MPH across parts of MT and WY. With hot temperatures and little recent rainfall persisting, afternoon RH values should remain quite low, generally below 20-25%. With increasing winds, receptive fuels, and persistent dry conditions, periods of elevated fire-weather conditions are likely over parts of the northern Rockies. ...Dry Thunder... Across parts of the eastern Great Basin and central Rockies, lingering monsoon moisture will likely support isolated to scattered thunderstorms Monday afternoon. A mixed mode of wet and dry storms is expected with PWATs of 0.7-1 inch, and increasing mid-level flow supporting faster storm speeds. While there is some potential for drier strikes, fuels across much of the area are less receptive and storms should generally cluster with time. This suggests any dry lightning potential will be limited. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

000
ABPZ20 KNHC 081749
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Sun Sep 8 2024

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

Offshore of Southwestern Mexico:
An area of low pressure is forecast to form during the early to
middle part of the week, near or just to the south of the coast of
southern or southwestern Mexico. Environmental conditions are
forecast to be conducive for some gradual development of this
system, and a tropical depression could form during the middle to
latter part of this week while it moves generally northwestward,
near the coast of southwestern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...60 percent.

$$
Forecaster Brown

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1139 AM CDT Sun Sep 08 2024 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF WESTERN INTO CENTRAL NEW YORK... ...SUMMARY... Thunderstorms will be possible on Monday in parts of the lower Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Some storms may produce damaging wind gusts over western into central New York. ...Synopsis... A pronounced mid-level trough will eject into the Atlantic while weaker mid-level troughs, embedded in mainly zonal flow, traverse the Pacific Northwest and Northern Plains tomorrow (Monday). Surface high pressure will dominate the Midwest to Atlantic Seaboard while surface troughing becomes established over the central and northern Plains. An embedded mid-level impulse will pivot around the backside of the East Coast trough and provide adequate lift for at least scattered thunderstorms over NY and immediate surrounding areas. Meanwhile, strong surface heating and orographic lift will encourage isolated to scattered thunderstorm development over the Great Basin into the Four Corners region, with scattered thunderstorm development also possible over the Northern Plains with the passage of a mid-level trough. Finally, scattered thunderstorms may also develop by afternoon peak heating amid a moist boundary layer along the Gulf Coast into FL. ...Portions of New York... A 500 mb speed max will rotate around the backside of the East Coast trough by afternoon, when boundary-layer heating will support the steepening of low-level lapse rates to about 7.5-8 C/km, resulting in over 500 J/kg MLCAPE over central NY. While buoyancy will be weak overall, the 500 mb speed max overspreading the region will result in elongated mid/upper-level hodographs. As such, highly sheared and low-topped multicell storms are expected to develop during the afternoon. Some of the stronger storms may produce potentially damaging wind gusts, necessitating the introduction of Category 1/Marginal risk probabilities. ..Squitieri.. 09/08/2024 Read more