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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Wed Sep 03 2025 Valid 051200Z - 061200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A couple strong thunderstorms will be possible from the Ohio/Tennessee Valleys to the southern Plains and across parts of Oregon on Friday, though the potential for organized severe storms appears low. ...Discussion... A broad midlevel trough centered on the Great Lakes region will shift slightly eastward through the period, as a midlevel speed maximum advances east-northeastward from the Great Lakes into Quebec. A related surface low will track northeastward from Ontario into Quebec, while a cold front extents southwestward across the OH Valley to a separate surface low in the southern Great Plains. Given a slow east-southeastward motion of the front and large-scale forcing for ascent lagging behind, thunderstorms may tend to be anafrontal. However, if any thunderstorms can develop along/immediately ahead of the front from the OH/TN Valleys into the southern Plains, ample moisture/buoyancy and around 30 kt of midlevel west-southwesterly flow would conditionally support a couple strong/loosely organized storms. Farther west, a midlevel trough will approach the Pacific Northwest through the period. Related forcing for ascent will promote scattered thunderstorms across OR. Moderately enhanced midlevel flow and steep deep-layer lapse rates may promote a couple strong storms capable of producing locally strong wind gusts. ..Weinman.. 09/03/2025 Read more

5-Day Uncertainty Track last updated Wed, 03 Sep 2025 17:49:01 GMT


Wind Speed Probabilities last updated Wed, 03 Sep 2025 15:26:46 GMT

Issued at 1100 AM MST Wed Sep 03 2025 000 WTPZ32 KNHC 031748 TCPEP2 BULLETIN Hurricane Lorena Intermediate Advisory Number 7A NWS National Hurricane Center Miami FL EP122025 1100 AM MST Wed Sep 03 2025 ...AIR FORCE RECONNAISSANCE CURRENTLY INVESTIGATING LORENA... ...HEAVY RAINFALL AND LIFE-THREATENING FLASH FLOODING SPREADING NORTHWARD ACROSS BAJA CALIFORNIA SUR... SUMMARY OF 1100 AM MST...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...22.5N 112.1W ABOUT 145 MI...230 KM W OF CABO SAN LUCAS MEXICO ABOUT 160 MI...255 KM S OF CABO SAN LAZARO MEXICO MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H PRESENT MOVEMENT...NW OR 320 DEGREES AT 16 MPH...26 KM/H MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * West Coast of Baja California Sur from Santa Fe to Punta Abreojos A Tropical Storm Watch is in effect for... * West Coast of Baja California Sur from Cabo San Lucas northward to Santa Fe. * West Coast of Baja California Sur from north of Punta Abreojos to Punta Eugenia A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area. Interests elsewhere on the Baja California peninsula and in northwestern Mexico should monitor the progress of Lorena. Additional watches or warnings may be required later today. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM MST (1800 UTC), the center of Hurricane Lorena was located near latitude 22.5 North, longitude 112.1 West. Lorena is moving toward the northwest near 16 mph (26 km/h), and this motion with a decrease in forward speed is expected through early Thursday. A generally slow northward motion is expected late Thursday and early Friday, with a gradual turn toward the northeast by late Friday. On the forecast track, the center of Lorena is expected to move parallel to the west coast of the Baja California peninsula through tonight and then approach the coast late Thursday through Friday. Maximum sustained winds are near 80 mph (130 km/h) with higher gusts. Rapid strengthening is forecast to continue through this evening. Fast weakening is expected to begin on Thursday, and Lorena could weaken back to a tropical storm by Friday. Hurricane-force winds extend outward up to 15 miles (30 km) from the center and tropical-storm-force winds extend outward up to 70 miles (110 km). The latest minimum central pressure based on Air Force Reserve reconnaissance aircraft data is 985 mb (29.09 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Lorena can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP2 and WMO header WTPZ42 KNHC. RAINFALL: Bands of heavy rainfall will continue to impact Baja California Sur and move into southeastern Baja California and southwestern Sonora by Thursday, with this rainfall potentially persisting through Friday. Rainfall totals of 5 to 10 inches, with maximum amounts of 15 inches, are possible across portions of Baja California Sur, far southeast Baja California and southwestern Sonora through Friday. This will bring the risk of life-threatening flash floods and mudslides, especially in areas of higher terrain. Within the moisture surge ahead of Lorena, 1 to 3 inches of rain, with localized totals up to 4 inches, are expected from the Mexico states of Sinaloa northward into Arizona through Friday, bringing the potential for isolated to scattered flash flooding. For a complete depiction of forecast rainfall and flash flooding associated with Lorena, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_ep2.shtml?rainqpf WIND: Tropical storm conditions are expected in the warning area beginning tonight, and spreading northward within the warning area in Baja California Sur through Thursday and into Friday. Tropical storm conditions are possible within the watch area south of Santa Fe through tonight, and in the watch area north of Punta Abreojos Thursday night and early Friday. SURF: Swells generated by Lorena will continue affecting portions of the south and west coasts of Baja California Sur through Friday. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 200 PM MST. $$ Forecaster Hagen/Brown

...AIR FORCE RECONNAISSANCE CURRENTLY INVESTIGATING LORENA... ...HEAVY RAINFALL AND LIFE-THREATENING FLASH FLOODING SPREADING NORTHWARD ACROSS BAJA CALIFORNIA SUR... As of 11:00 AM MST Wed Sep 03 the center of Lorena was located near 22.5, -112.1 with movement NW at 16 mph. The minimum central pressure was 985 mb with maximum sustained winds of about 80 mph.

000
ABPZ20 KNHC 031745
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Sep 3 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Kiko, located in the East Pacific basin well east-southeast of the
Hawaiian Islands. Kiko is expected to cross into the central
Pacific basin over the weekend.

The National Hurricane Center is also issuing advisories on
Hurricane Lorena, located in the East Pacific basin around 145
miles west of Cabo San Lucas, Mexico.

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Hagen

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1231 PM CDT Wed Sep 03 2025 Valid 041200Z - 051200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE TENNESSEE VALLEY AND SOUTHERN APPALACHIANS NORTHWARD INTO NEW YORK... ...SUMMARY... Scattered strong thunderstorms capable of producing locally damaging wind gusts may impact a corridor from the Tennessee Valley and southern Appalachians northward through northern New York on Thursday. ...Synopsis... A deep/vertically stacked low pressure system will retrograde slightly westward over Ontario through the forecast period, while broad large-scale troughing encompasses much of the eastern CONUS. An embedded midlevel trough will track eastward across the Lower Great Lakes during the day, while a related cold front extending from NY south-southwestward along the Appalachians moves gradually eastward. ...TN Valley and Southern Appalachians northward into NY... Despite poor midlevel lapse rates, diurnal heating amid middle/upper 50 to lower 60s dewpoints will result in a corridor of weak to locally moderate surface-based buoyancy ahead of the front during the afternoon. Scattered thunderstorms are expected along/ahead of the front, where 30-40 kt of effective shear will promote loosely organized multicell clusters and line segments. The stronger storm clusters will be capable of producing locally damaging wind gusts through the afternoon. ...Northern Plains... On the backside of the large-scale trough, a robust midlevel speed maximum will move into the northern Plains during the day. Strong forcing for ascent and cold temperatures aloft will support isolated thunderstorms. While deep-layer shear will be sufficient for organized storms, the post-frontal nature of this activity should limit the overall severe risk. ..Weinman.. 09/03/2025 Read more