Aggregator

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1116 AM CDT Sun Sep 08 2024 Valid 081630Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms appear unlikely through tonight. ...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. ..Gleason/Halbert.. 09/08/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1110 AM CDT Sun Sep 08 2024 Valid 081700Z - 091200Z No changes are needed to the ongoing forecast. ..Wendt.. 09/08/2024 .PREV DISCUSSION... /ISSUED 0201 AM CDT Sun Sep 08 2024/ ...Synopsis... Broad troughing over the Pacific Northwest is forecast to intensify as a shortwave perturbation moves onshore across parts of WA and OR today. As the shortwave trough intensifies, flow aloft should also increase as it overspreads the Northwest and Great Basin. Showers and thunderstorms, along with gusty, winds are likely across much of the West, with elevated fire-weather potential. ...Dry Thunder... Beneath the cold core of the upper trough moving inland, a thunderstorm may be ongoing through the morning hours across portions of the Pacific Northwest. Greater storm coverage is expected to develop through the day, as daytime heating and lift from the upper trough interact with deepening mid-level moisture. Model soundings show weak buoyancy atop warm and dry low levels and storm motions greater than 20 kt. With poor precipitation efficiency expected, isolated to widely scattered dry thunderstorms appear likely over receptive fuels. Confidence in dry thunderstorm coverage is greatest across portions of the northern and central Cascades, into eastern ID and far southwestern MT. Scattered thunderstorms are also possible farther south across the southern Great Basin and southern CA. Displaced from the stronger flow aloft, and with access to more robust monsoon moisture, a wetter storm mode is expected. A few drier strikes are still possible outside of the wetter cores within receptive fuels, but the coverage of drier storms appears limited. ...Northern Great Basin and the Cascades... As the trough moves inland, a belt of stronger mid-level flow is expected to intensify over parts of the northern Great Basin and the southern Cascades. The stronger flow aloft will support an increase in surface winds to 15-25 mph. Residual warm temperatures beneath the weakening ridge and the increase in downslope winds will favor drier low levels, with RH minimums below 15% likely. Widespread elevated to near-critical fire-weather conditions are possible across the northern Sierra and Great Basin, where the dry and breezy conditions will overlap with areas of dry fuels. Farther north in the lee of the Cascades, gusty downslope and gap winds may also support brief elevated fire-weather potential as stronger flow aloft develops. However, some humidity recovery will eventually occur as marine influence will increase with time, potentially limiting the coverage and duration of fire-weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Sun Sep 08 2024 Valid 081300Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Though a few strong thunderstorm gusts may be noted in the interior Northwest and central High Plains, severe potential appears too low and disorganized for an outlook area. ...Synopsis/Discussion... In mid/upper levels, the large-scale pattern will deamplify somewhat over the CONUS this period, but maintain a mean trough in the Great Lakes and eastern CONUS, and mean ridging over the Intermountain West and Southwestern deserts. A shortwave trough -- evident in moisture-channel imagery over the interior of OR/WA into far northern CA -- is forecast to continue weakening as it moves northeastward, crossing the northern Rockies between 06-12Z. Still, associated cooling aloft and midlevel moisture, over pockets of marginally favorable low-level moisture and diurnal surface heating, will contribute to general thunderstorm potential in parts of the interior Northwest and Intermountain West. A few of these high- based cells may produce strong gusts, but severe potential appears to be limited by lack of greater moisture/buoyancy. Farther east over the central Rockies and adjoining High Plains, isolated to widely scattered thunderstorms are possible this afternoon into evening. Activity should be related to diabatic heating of elevated terrain, along with lift near a surface lee trough, and a corridor of meager but sufficient low-level moisture. Beneath strongly difluent but weak west to northwest flow in mid/ upper levels, bulk shear should be modest, despite considerable veering with height. Here too, a few cells may produce strong gusts through a well-mixed subcloud layer, and a severe gust cannot be ruled out. However, severe potential appears too isolated, poorly focused and conditional for a categorical risk area. Elsewhere, isolated to scattered thunderstorms will be possible in a very moist air mass (but with poor lapse rates) from parts of the Gulf Coast States across FL and the southern Atlantic Coast. ..Edwards/Kerr.. 09/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Sun Sep 08 2024 Valid 081300Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Though a few strong thunderstorm gusts may be noted in the interior Northwest and central High Plains, severe potential appears too low and disorganized for an outlook area. ...Synopsis/Discussion... In mid/upper levels, the large-scale pattern will deamplify somewhat over the CONUS this period, but maintain a mean trough in the Great Lakes and eastern CONUS, and mean ridging over the Intermountain West and Southwestern deserts. A shortwave trough -- evident in moisture-channel imagery over the interior of OR/WA into far northern CA -- is forecast to continue weakening as it moves northeastward, crossing the northern Rockies between 06-12Z. Still, associated cooling aloft and midlevel moisture, over pockets of marginally favorable low-level moisture and diurnal surface heating, will contribute to general thunderstorm potential in parts of the interior Northwest and Intermountain West. A few of these high- based cells may produce strong gusts, but severe potential appears to be limited by lack of greater moisture/buoyancy. Farther east over the central Rockies and adjoining High Plains, isolated to widely scattered thunderstorms are possible this afternoon into evening. Activity should be related to diabatic heating of elevated terrain, along with lift near a surface lee trough, and a corridor of meager but sufficient low-level moisture. Beneath strongly difluent but weak west to northwest flow in mid/ upper levels, bulk shear should be modest, despite considerable veering with height. Here too, a few cells may produce strong gusts through a well-mixed subcloud layer, and a severe gust cannot be ruled out. However, severe potential appears too isolated, poorly focused and conditional for a categorical risk area. Elsewhere, isolated to scattered thunderstorms will be possible in a very moist air mass (but with poor lapse rates) from parts of the Gulf Coast States across FL and the southern Atlantic Coast. ..Edwards/Kerr.. 09/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Sun Sep 08 2024 Valid 081300Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Though a few strong thunderstorm gusts may be noted in the interior Northwest and central High Plains, severe potential appears too low and disorganized for an outlook area. ...Synopsis/Discussion... In mid/upper levels, the large-scale pattern will deamplify somewhat over the CONUS this period, but maintain a mean trough in the Great Lakes and eastern CONUS, and mean ridging over the Intermountain West and Southwestern deserts. A shortwave trough -- evident in moisture-channel imagery over the interior of OR/WA into far northern CA -- is forecast to continue weakening as it moves northeastward, crossing the northern Rockies between 06-12Z. Still, associated cooling aloft and midlevel moisture, over pockets of marginally favorable low-level moisture and diurnal surface heating, will contribute to general thunderstorm potential in parts of the interior Northwest and Intermountain West. A few of these high- based cells may produce strong gusts, but severe potential appears to be limited by lack of greater moisture/buoyancy. Farther east over the central Rockies and adjoining High Plains, isolated to widely scattered thunderstorms are possible this afternoon into evening. Activity should be related to diabatic heating of elevated terrain, along with lift near a surface lee trough, and a corridor of meager but sufficient low-level moisture. Beneath strongly difluent but weak west to northwest flow in mid/ upper levels, bulk shear should be modest, despite considerable veering with height. Here too, a few cells may produce strong gusts through a well-mixed subcloud layer, and a severe gust cannot be ruled out. However, severe potential appears too isolated, poorly focused and conditional for a categorical risk area. Elsewhere, isolated to scattered thunderstorms will be possible in a very moist air mass (but with poor lapse rates) from parts of the Gulf Coast States across FL and the southern Atlantic Coast. ..Edwards/Kerr.. 09/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Sun Sep 08 2024 Valid 081300Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Though a few strong thunderstorm gusts may be noted in the interior Northwest and central High Plains, severe potential appears too low and disorganized for an outlook area. ...Synopsis/Discussion... In mid/upper levels, the large-scale pattern will deamplify somewhat over the CONUS this period, but maintain a mean trough in the Great Lakes and eastern CONUS, and mean ridging over the Intermountain West and Southwestern deserts. A shortwave trough -- evident in moisture-channel imagery over the interior of OR/WA into far northern CA -- is forecast to continue weakening as it moves northeastward, crossing the northern Rockies between 06-12Z. Still, associated cooling aloft and midlevel moisture, over pockets of marginally favorable low-level moisture and diurnal surface heating, will contribute to general thunderstorm potential in parts of the interior Northwest and Intermountain West. A few of these high- based cells may produce strong gusts, but severe potential appears to be limited by lack of greater moisture/buoyancy. Farther east over the central Rockies and adjoining High Plains, isolated to widely scattered thunderstorms are possible this afternoon into evening. Activity should be related to diabatic heating of elevated terrain, along with lift near a surface lee trough, and a corridor of meager but sufficient low-level moisture. Beneath strongly difluent but weak west to northwest flow in mid/ upper levels, bulk shear should be modest, despite considerable veering with height. Here too, a few cells may produce strong gusts through a well-mixed subcloud layer, and a severe gust cannot be ruled out. However, severe potential appears too isolated, poorly focused and conditional for a categorical risk area. Elsewhere, isolated to scattered thunderstorms will be possible in a very moist air mass (but with poor lapse rates) from parts of the Gulf Coast States across FL and the southern Atlantic Coast. ..Edwards/Kerr.. 09/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Sun Sep 08 2024 Valid 081300Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Though a few strong thunderstorm gusts may be noted in the interior Northwest and central High Plains, severe potential appears too low and disorganized for an outlook area. ...Synopsis/Discussion... In mid/upper levels, the large-scale pattern will deamplify somewhat over the CONUS this period, but maintain a mean trough in the Great Lakes and eastern CONUS, and mean ridging over the Intermountain West and Southwestern deserts. A shortwave trough -- evident in moisture-channel imagery over the interior of OR/WA into far northern CA -- is forecast to continue weakening as it moves northeastward, crossing the northern Rockies between 06-12Z. Still, associated cooling aloft and midlevel moisture, over pockets of marginally favorable low-level moisture and diurnal surface heating, will contribute to general thunderstorm potential in parts of the interior Northwest and Intermountain West. A few of these high- based cells may produce strong gusts, but severe potential appears to be limited by lack of greater moisture/buoyancy. Farther east over the central Rockies and adjoining High Plains, isolated to widely scattered thunderstorms are possible this afternoon into evening. Activity should be related to diabatic heating of elevated terrain, along with lift near a surface lee trough, and a corridor of meager but sufficient low-level moisture. Beneath strongly difluent but weak west to northwest flow in mid/ upper levels, bulk shear should be modest, despite considerable veering with height. Here too, a few cells may produce strong gusts through a well-mixed subcloud layer, and a severe gust cannot be ruled out. However, severe potential appears too isolated, poorly focused and conditional for a categorical risk area. Elsewhere, isolated to scattered thunderstorms will be possible in a very moist air mass (but with poor lapse rates) from parts of the Gulf Coast States across FL and the southern Atlantic Coast. ..Edwards/Kerr.. 09/08/2024 Read more

000
ABPZ20 KNHC 081136
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 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...50 percent.

$$
Forecaster Brown

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Sun Sep 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...Wednesday/Day 4 to Friday/Day 6... An upper-level ridge is forecast to move across the north-central U.S. on Wednesday, as a trough develops in the western U.S. An upper-level low is forecast to move across the northwestern states from Wednesday to Friday. Ahead of the trough, thunderstorms will be possible each day from the Intermountain west eastward into the central and northern Plains. At this time, the potential for severe may be limited by instability, which is generally forecast to remain weak across most of the western and central U.S. In the Gulf Coast region, some model forecasts have a tropical system becoming organized in the northern Gulf from Wednesday to Friday. If this system materializes and can move onshore, the day with the greatest potential to impact the central Gulf Coast would be Thursday. A tornado threat could materialize as the system moves inland, depending upon its overall strength. ...Saturday/Day 7 and Sunday/Day 8... A shortwave trough is forecast to move eastward across the north-central U.S. on Saturday, as an upper-level low moves across the Ohio Valley and into the Great Lakes from Saturday into Sunday. Although the potential for severe storms over the weekend appears to be low at this time, substantial uncertainty exists at this extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Sun Sep 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...Wednesday/Day 4 to Friday/Day 6... An upper-level ridge is forecast to move across the north-central U.S. on Wednesday, as a trough develops in the western U.S. An upper-level low is forecast to move across the northwestern states from Wednesday to Friday. Ahead of the trough, thunderstorms will be possible each day from the Intermountain west eastward into the central and northern Plains. At this time, the potential for severe may be limited by instability, which is generally forecast to remain weak across most of the western and central U.S. In the Gulf Coast region, some model forecasts have a tropical system becoming organized in the northern Gulf from Wednesday to Friday. If this system materializes and can move onshore, the day with the greatest potential to impact the central Gulf Coast would be Thursday. A tornado threat could materialize as the system moves inland, depending upon its overall strength. ...Saturday/Day 7 and Sunday/Day 8... A shortwave trough is forecast to move eastward across the north-central U.S. on Saturday, as an upper-level low moves across the Ohio Valley and into the Great Lakes from Saturday into Sunday. Although the potential for severe storms over the weekend appears to be low at this time, substantial uncertainty exists at this extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Sun Sep 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...Wednesday/Day 4 to Friday/Day 6... An upper-level ridge is forecast to move across the north-central U.S. on Wednesday, as a trough develops in the western U.S. An upper-level low is forecast to move across the northwestern states from Wednesday to Friday. Ahead of the trough, thunderstorms will be possible each day from the Intermountain west eastward into the central and northern Plains. At this time, the potential for severe may be limited by instability, which is generally forecast to remain weak across most of the western and central U.S. In the Gulf Coast region, some model forecasts have a tropical system becoming organized in the northern Gulf from Wednesday to Friday. If this system materializes and can move onshore, the day with the greatest potential to impact the central Gulf Coast would be Thursday. A tornado threat could materialize as the system moves inland, depending upon its overall strength. ...Saturday/Day 7 and Sunday/Day 8... A shortwave trough is forecast to move eastward across the north-central U.S. on Saturday, as an upper-level low moves across the Ohio Valley and into the Great Lakes from Saturday into Sunday. Although the potential for severe storms over the weekend appears to be low at this time, substantial uncertainty exists at this extended range. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CDT Sun Sep 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... ...Wednesday/Day 4 to Friday/Day 6... An upper-level ridge is forecast to move across the north-central U.S. on Wednesday, as a trough develops in the western U.S. An upper-level low is forecast to move across the northwestern states from Wednesday to Friday. Ahead of the trough, thunderstorms will be possible each day from the Intermountain west eastward into the central and northern Plains. At this time, the potential for severe may be limited by instability, which is generally forecast to remain weak across most of the western and central U.S. In the Gulf Coast region, some model forecasts have a tropical system becoming organized in the northern Gulf from Wednesday to Friday. If this system materializes and can move onshore, the day with the greatest potential to impact the central Gulf Coast would be Thursday. A tornado threat could materialize as the system moves inland, depending upon its overall strength. ...Saturday/Day 7 and Sunday/Day 8... A shortwave trough is forecast to move eastward across the north-central U.S. on Saturday, as an upper-level low moves across the Ohio Valley and into the Great Lakes from Saturday into Sunday. Although the potential for severe storms over the weekend appears to be low at this time, substantial uncertainty exists at this extended range. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM 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. ...DISCUSSION... A shortwave ridge is forecast to move eastward across the Great Lakes and Ohio Valley on Tuesday, a shortwave trough moves across the northern Plains. At the surface, a cold front is forecast to advance southeastward across the central and northern Plains. Thunderstorm development will be possible along and near parts of the front, and further west in the higher terrain of the central and northern Rockies. Additional thunderstorms will be possible in the Gulf Coast region along the northern edge of a moist airmass. No severe threat is expected across the U.S. on Tuesday and Tuesday night. ..Broyles.. 09/08/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM 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. ...DISCUSSION... A shortwave ridge is forecast to move eastward across the Great Lakes and Ohio Valley on Tuesday, a shortwave trough moves across the northern Plains. At the surface, a cold front is forecast to advance southeastward across the central and northern Plains. Thunderstorm development will be possible along and near parts of the front, and further west in the higher terrain of the central and northern Rockies. Additional thunderstorms will be possible in the Gulf Coast region along the northern edge of a moist airmass. No severe threat is expected across the U.S. on Tuesday and Tuesday night. ..Broyles.. 09/08/2024 Read more