Aggregator

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Mon Sep 09 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. ...DISCUSSION... A shortwave ridge will move eastward across the Great Lakes region on Tuesday, as an upper-level trough develops near the West Coast. Southwesterly mid-level flow will be in place from the Intermountain West into the central and northern Rockies. Isolated to scattered thunderstorms will be possible on Tuesday in the higher terrain from the vicinity of the Four Corners northward into the northern Rockies and northeastward into the upper Mississippi Valley. Additional storms will be possible along the Gulf Coast, near the northern edge of a moist airmass. No severe threat is expected across the U.S. on Tuesday and Tuesday night. ..Broyles.. 09/09/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Mon Sep 09 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. ...DISCUSSION... A shortwave ridge will move eastward across the Great Lakes region on Tuesday, as an upper-level trough develops near the West Coast. Southwesterly mid-level flow will be in place from the Intermountain West into the central and northern Rockies. Isolated to scattered thunderstorms will be possible on Tuesday in the higher terrain from the vicinity of the Four Corners northward into the northern Rockies and northeastward into the upper Mississippi Valley. Additional storms will be possible along the Gulf Coast, near the northern edge of a moist airmass. No severe threat is expected across the U.S. on Tuesday and Tuesday night. ..Broyles.. 09/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 09 2024 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN GREAT LAKES VICINITY... ...SUMMARY... Thunderstorms will be possible today over parts of the eastern Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Isolated storms may produce damaging wind gusts over western and central New York State. ...Synopsis... A large upper ridge will remain in place over the Central CONUS flanked by broad trouging to the west and a lingering upper low over eastern Canada. Behind the upper low, a secondary embedded shortwave trough and speed max are forecast to move south out of western Ontario and over the Great Lakes, providing adequate lift for scattered thunderstorms over parts of the Northeast. To the west, scattered thunderstorms are likely over the Great Basin into the Four Corners, with a few thunderstorms possible over the Northern Plains ahead of the western US trough. Finally, scattered thunderstorms may also develop by afternoon peak heating along the Gulf Coast into FL and near the outer bands of PTC6. ...Great Lakes vicinity... As the aforementioned mid-level speed max approaches from southern Canada, shower and thunderstorm activity should begin to increase in coverage and intensity in the vicinity of Lakes Erie/Ontario, as well as over portions of northwestern NY State by mid morning. Limited, but adequate, surface moisture (dewpoints in the mid 50s to near 60 F), combined with daytime heating, and 500 mb temps of -18 to -20C will support weak destabilization (MLCAPE 500-700 J/kg) across parts of the lower Great Lakes and Northeast. Low-topped bands or clusters of predominately multicell storms are likely, and may briefly organize owing to increasing flow aloft aiding deep-layer shear to near 30 kt. Despite the weak buoyancy, fairly steep low-level lapse rates (~7 C/km) beneath the upper low, may support a few damaging gusts and instances of small hail with the strongest storms through the afternoon. Convection should eventually outrun the more robust buoyancy and weaken to the southeast into parts of northern PA and southern New England this evening. ..Lyons.. 09/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 09 2024 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN GREAT LAKES VICINITY... ...SUMMARY... Thunderstorms will be possible today over parts of the eastern Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Isolated storms may produce damaging wind gusts over western and central New York State. ...Synopsis... A large upper ridge will remain in place over the Central CONUS flanked by broad trouging to the west and a lingering upper low over eastern Canada. Behind the upper low, a secondary embedded shortwave trough and speed max are forecast to move south out of western Ontario and over the Great Lakes, providing adequate lift for scattered thunderstorms over parts of the Northeast. To the west, scattered thunderstorms are likely over the Great Basin into the Four Corners, with a few thunderstorms possible over the Northern Plains ahead of the western US trough. Finally, scattered thunderstorms may also develop by afternoon peak heating along the Gulf Coast into FL and near the outer bands of PTC6. ...Great Lakes vicinity... As the aforementioned mid-level speed max approaches from southern Canada, shower and thunderstorm activity should begin to increase in coverage and intensity in the vicinity of Lakes Erie/Ontario, as well as over portions of northwestern NY State by mid morning. Limited, but adequate, surface moisture (dewpoints in the mid 50s to near 60 F), combined with daytime heating, and 500 mb temps of -18 to -20C will support weak destabilization (MLCAPE 500-700 J/kg) across parts of the lower Great Lakes and Northeast. Low-topped bands or clusters of predominately multicell storms are likely, and may briefly organize owing to increasing flow aloft aiding deep-layer shear to near 30 kt. Despite the weak buoyancy, fairly steep low-level lapse rates (~7 C/km) beneath the upper low, may support a few damaging gusts and instances of small hail with the strongest storms through the afternoon. Convection should eventually outrun the more robust buoyancy and weaken to the southeast into parts of northern PA and southern New England this evening. ..Lyons.. 09/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 09 2024 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN GREAT LAKES VICINITY... ...SUMMARY... Thunderstorms will be possible today over parts of the eastern Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Isolated storms may produce damaging wind gusts over western and central New York State. ...Synopsis... A large upper ridge will remain in place over the Central CONUS flanked by broad trouging to the west and a lingering upper low over eastern Canada. Behind the upper low, a secondary embedded shortwave trough and speed max are forecast to move south out of western Ontario and over the Great Lakes, providing adequate lift for scattered thunderstorms over parts of the Northeast. To the west, scattered thunderstorms are likely over the Great Basin into the Four Corners, with a few thunderstorms possible over the Northern Plains ahead of the western US trough. Finally, scattered thunderstorms may also develop by afternoon peak heating along the Gulf Coast into FL and near the outer bands of PTC6. ...Great Lakes vicinity... As the aforementioned mid-level speed max approaches from southern Canada, shower and thunderstorm activity should begin to increase in coverage and intensity in the vicinity of Lakes Erie/Ontario, as well as over portions of northwestern NY State by mid morning. Limited, but adequate, surface moisture (dewpoints in the mid 50s to near 60 F), combined with daytime heating, and 500 mb temps of -18 to -20C will support weak destabilization (MLCAPE 500-700 J/kg) across parts of the lower Great Lakes and Northeast. Low-topped bands or clusters of predominately multicell storms are likely, and may briefly organize owing to increasing flow aloft aiding deep-layer shear to near 30 kt. Despite the weak buoyancy, fairly steep low-level lapse rates (~7 C/km) beneath the upper low, may support a few damaging gusts and instances of small hail with the strongest storms through the afternoon. Convection should eventually outrun the more robust buoyancy and weaken to the southeast into parts of northern PA and southern New England this evening. ..Lyons.. 09/09/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Mon Sep 09 2024 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE EASTERN GREAT LAKES VICINITY... ...SUMMARY... Thunderstorms will be possible today over parts of the eastern Great Lakes, along the Gulf Coast, and from the Four Corners northward into the northern Plains. Isolated storms may produce damaging wind gusts over western and central New York State. ...Synopsis... A large upper ridge will remain in place over the Central CONUS flanked by broad trouging to the west and a lingering upper low over eastern Canada. Behind the upper low, a secondary embedded shortwave trough and speed max are forecast to move south out of western Ontario and over the Great Lakes, providing adequate lift for scattered thunderstorms over parts of the Northeast. To the west, scattered thunderstorms are likely over the Great Basin into the Four Corners, with a few thunderstorms possible over the Northern Plains ahead of the western US trough. Finally, scattered thunderstorms may also develop by afternoon peak heating along the Gulf Coast into FL and near the outer bands of PTC6. ...Great Lakes vicinity... As the aforementioned mid-level speed max approaches from southern Canada, shower and thunderstorm activity should begin to increase in coverage and intensity in the vicinity of Lakes Erie/Ontario, as well as over portions of northwestern NY State by mid morning. Limited, but adequate, surface moisture (dewpoints in the mid 50s to near 60 F), combined with daytime heating, and 500 mb temps of -18 to -20C will support weak destabilization (MLCAPE 500-700 J/kg) across parts of the lower Great Lakes and Northeast. Low-topped bands or clusters of predominately multicell storms are likely, and may briefly organize owing to increasing flow aloft aiding deep-layer shear to near 30 kt. Despite the weak buoyancy, fairly steep low-level lapse rates (~7 C/km) beneath the upper low, may support a few damaging gusts and instances of small hail with the strongest storms through the afternoon. Convection should eventually outrun the more robust buoyancy and weaken to the southeast into parts of northern PA and southern New England this evening. ..Lyons.. 09/09/2024 Read more

000
ABPZ20 KNHC 090527
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM 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 middle part
of the week, near or just to the south 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 middle to latter part of this week while it
moves generally north-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 Kelly

Canyon Lake has been closed to all watercraft so the water can be used against the First Thunder Fire. Houses in the area are under watch for evacuation. KFYR TV (Bismarck, North Dakota), Sept. 3, 2024.

Nonessential water use has been banned between 9am and 5pm in the town of Northampton, Massachusetts. Outdoor water use is not restricted between 5pm and 9am.

There have been multiple grass fires over the past week in northern Alabama near Decatur. The fires are due in part to the dry weather, as the region is under a severe drought. WAFF News (Huntsville, Alabama), Sept. 5, 2024.

A burn ban has been put in place in Livingston county, Kentucky, to reduce the risk of wildfires. The ban will be in place until further notice. WPSD 6 (Paducah, Kentucky), Sept. 3, 2024.

A burn ban has been put in place in Lafayette County, Miss., due to high risk of wildfires during the current drought. Fox13 Memphis (Memphis, Tenn.), Sept. 4, 2024.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Sun Sep 08 2024 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...01z Update... Evening water vapor imagery shows a prominent mid-level ridge remains in place over much of the CONUS, with surface high pressure favoring dry and quiescent weather over much of the country. To the east of the ridge, an upper low over the Northeast and eastern Canada is slowly filling. A cold front trailing south of the low has moved mostly offshore, but was supporting scattered showers and thunderstorms in the northern Gulf of Mexico and across parts of FL. Continued offshore flow ahead of the surface high moving slowly south and east should keep much of this activity offshore or confined to the immediate coast through the next 12 hours. Storms should gradually diminish in coverage and intensity through the remainder of the evening. To the west, weak and broader troughing is ongoing over the West Coast with an embedded shortwave perturbation crossing the northern Rockies. Monsoon moisture advection ahead of theses features is supporting scattered thunderstorms across much of the Intermoutnain West, into the northern Rockies and across much of the Desert Southwest. Scattered showers and thunderstorms appear likely to persist into this evening as the weak trough shifts slowly eastward, especially across parts of ID and the Great Basin where more clustering has occurred. Storms are predominately high-based in nature, owing to steep low-level lapse rates, hot temperatures and the limited monsoon moisture. This could support an occasional dry downburst with the more robust cores, mainly over parts of southern CA. However, limited deep-layer shear and weak overall buoyancy suggests these storms are unlikely to be meaningfully organized or persistent. Thus, will continue with severe probs less than 5%. Storms should begin to decrease in coverage this evening with the loss of diurnal heating and mid-level drying. Otherwise, the severe risk appears limited across much of the country. ..Lyons.. 09/09/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 PM CDT Sun Sep 08 2024 Valid 090100Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...01z Update... Evening water vapor imagery shows a prominent mid-level ridge remains in place over much of the CONUS, with surface high pressure favoring dry and quiescent weather over much of the country. To the east of the ridge, an upper low over the Northeast and eastern Canada is slowly filling. A cold front trailing south of the low has moved mostly offshore, but was supporting scattered showers and thunderstorms in the northern Gulf of Mexico and across parts of FL. Continued offshore flow ahead of the surface high moving slowly south and east should keep much of this activity offshore or confined to the immediate coast through the next 12 hours. Storms should gradually diminish in coverage and intensity through the remainder of the evening. To the west, weak and broader troughing is ongoing over the West Coast with an embedded shortwave perturbation crossing the northern Rockies. Monsoon moisture advection ahead of theses features is supporting scattered thunderstorms across much of the Intermoutnain West, into the northern Rockies and across much of the Desert Southwest. Scattered showers and thunderstorms appear likely to persist into this evening as the weak trough shifts slowly eastward, especially across parts of ID and the Great Basin where more clustering has occurred. Storms are predominately high-based in nature, owing to steep low-level lapse rates, hot temperatures and the limited monsoon moisture. This could support an occasional dry downburst with the more robust cores, mainly over parts of southern CA. However, limited deep-layer shear and weak overall buoyancy suggests these storms are unlikely to be meaningfully organized or persistent. Thus, will continue with severe probs less than 5%. Storms should begin to decrease in coverage this evening with the loss of diurnal heating and mid-level drying. Otherwise, the severe risk appears limited across much of the country. ..Lyons.. 09/09/2024 Read more

No watches are valid as of Sun Sep 8 23:57:02 UTC 2024.

No Mesoscale Discussions are in effect as of Sun Sep 8 23:57:02 UTC 2024.

000
ABPZ20 KNHC 082313
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM 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 Hagen

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