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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z A rather expansive IsoDryT area was added as scattered to widespread mixed wet/dry thunderstorms are expected across central Oregon/vicinity tomorrow with more isolated coverage into western Oregon and western/central Washington. Late evening and nocturnal thunderstorms are possible in portions of central/eastern/northwest Oregon and western Washington. While wetting rain is likely in portions of central/eastern Oregon, the amount of lightning and dry to very dry fuels as evident by new ignitions and active to extreme fire behavior on large fires in the region support the introduction of an IsoDryT area. Storms will track generally northward at 10-20 knots likely producing abundant lightning, including outside of the cores, with drier air moving into portions of southern/central Oregon behind them. Precipitable water values will range from 0.7-1.3" in the IsoDryT area and training of storms with some of those higher PWAT values will lead to wetting rain in areas. The onshore flow/marine layer is also precluding including more of coastal Oregon in the IsoDryT area as it looks to deepen tomorrow, but thunderstorms may go up the Coast Ranges late tomorrow. Deep pyroconvection remains possible on very active large wildfires in the Northwest, north Idaho, and California. A complicating factor in this forecast is the quantity of smoke that will be in the region from existing fires and being transported southward from Canada. ..Nauslar.. 09/04/2025 .PREV DISCUSSION... /ISSUED 1249 AM CDT Thu Sep 04 2025/ ...Synopsis... A secondary mid-level wave will traverse the Pacific Northwest on D2/Friday. This wave will bring much cooler temperatures, higher relative humidity, and potential for more widespread thunderstorm activity. While lightning efficiency may increase, increase coverage of thunderstorms and better organization with increasing shear should promote heavier cores and wetting rainfall potential. As such, no isolated thunderstorm areas were included at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z A rather expansive IsoDryT area was added as scattered to widespread mixed wet/dry thunderstorms are expected across central Oregon/vicinity tomorrow with more isolated coverage into western Oregon and western/central Washington. Late evening and nocturnal thunderstorms are possible in portions of central/eastern/northwest Oregon and western Washington. While wetting rain is likely in portions of central/eastern Oregon, the amount of lightning and dry to very dry fuels as evident by new ignitions and active to extreme fire behavior on large fires in the region support the introduction of an IsoDryT area. Storms will track generally northward at 10-20 knots likely producing abundant lightning, including outside of the cores, with drier air moving into portions of southern/central Oregon behind them. Precipitable water values will range from 0.7-1.3" in the IsoDryT area and training of storms with some of those higher PWAT values will lead to wetting rain in areas. The onshore flow/marine layer is also precluding including more of coastal Oregon in the IsoDryT area as it looks to deepen tomorrow, but thunderstorms may go up the Coast Ranges late tomorrow. Deep pyroconvection remains possible on very active large wildfires in the Northwest, north Idaho, and California. A complicating factor in this forecast is the quantity of smoke that will be in the region from existing fires and being transported southward from Canada. ..Nauslar.. 09/04/2025 .PREV DISCUSSION... /ISSUED 1249 AM CDT Thu Sep 04 2025/ ...Synopsis... A secondary mid-level wave will traverse the Pacific Northwest on D2/Friday. This wave will bring much cooler temperatures, higher relative humidity, and potential for more widespread thunderstorm activity. While lightning efficiency may increase, increase coverage of thunderstorms and better organization with increasing shear should promote heavier cores and wetting rainfall potential. As such, no isolated thunderstorm areas were included at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z A rather expansive IsoDryT area was added as scattered to widespread mixed wet/dry thunderstorms are expected across central Oregon/vicinity tomorrow with more isolated coverage into western Oregon and western/central Washington. Late evening and nocturnal thunderstorms are possible in portions of central/eastern/northwest Oregon and western Washington. While wetting rain is likely in portions of central/eastern Oregon, the amount of lightning and dry to very dry fuels as evident by new ignitions and active to extreme fire behavior on large fires in the region support the introduction of an IsoDryT area. Storms will track generally northward at 10-20 knots likely producing abundant lightning, including outside of the cores, with drier air moving into portions of southern/central Oregon behind them. Precipitable water values will range from 0.7-1.3" in the IsoDryT area and training of storms with some of those higher PWAT values will lead to wetting rain in areas. The onshore flow/marine layer is also precluding including more of coastal Oregon in the IsoDryT area as it looks to deepen tomorrow, but thunderstorms may go up the Coast Ranges late tomorrow. Deep pyroconvection remains possible on very active large wildfires in the Northwest, north Idaho, and California. A complicating factor in this forecast is the quantity of smoke that will be in the region from existing fires and being transported southward from Canada. ..Nauslar.. 09/04/2025 .PREV DISCUSSION... /ISSUED 1249 AM CDT Thu Sep 04 2025/ ...Synopsis... A secondary mid-level wave will traverse the Pacific Northwest on D2/Friday. This wave will bring much cooler temperatures, higher relative humidity, and potential for more widespread thunderstorm activity. While lightning efficiency may increase, increase coverage of thunderstorms and better organization with increasing shear should promote heavier cores and wetting rainfall potential. As such, no isolated thunderstorm areas were included at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z A rather expansive IsoDryT area was added as scattered to widespread mixed wet/dry thunderstorms are expected across central Oregon/vicinity tomorrow with more isolated coverage into western Oregon and western/central Washington. Late evening and nocturnal thunderstorms are possible in portions of central/eastern/northwest Oregon and western Washington. While wetting rain is likely in portions of central/eastern Oregon, the amount of lightning and dry to very dry fuels as evident by new ignitions and active to extreme fire behavior on large fires in the region support the introduction of an IsoDryT area. Storms will track generally northward at 10-20 knots likely producing abundant lightning, including outside of the cores, with drier air moving into portions of southern/central Oregon behind them. Precipitable water values will range from 0.7-1.3" in the IsoDryT area and training of storms with some of those higher PWAT values will lead to wetting rain in areas. The onshore flow/marine layer is also precluding including more of coastal Oregon in the IsoDryT area as it looks to deepen tomorrow, but thunderstorms may go up the Coast Ranges late tomorrow. Deep pyroconvection remains possible on very active large wildfires in the Northwest, north Idaho, and California. A complicating factor in this forecast is the quantity of smoke that will be in the region from existing fires and being transported southward from Canada. ..Nauslar.. 09/04/2025 .PREV DISCUSSION... /ISSUED 1249 AM CDT Thu Sep 04 2025/ ...Synopsis... A secondary mid-level wave will traverse the Pacific Northwest on D2/Friday. This wave will bring much cooler temperatures, higher relative humidity, and potential for more widespread thunderstorm activity. While lightning efficiency may increase, increase coverage of thunderstorms and better organization with increasing shear should promote heavier cores and wetting rainfall potential. As such, no isolated thunderstorm areas were included at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2031 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHWESTERN THROUGH NORTH CENTRAL VIRGINIA...NORTHWESTERN NORTH CAROLINA
Mesoscale Discussion 2031 NWS Storm Prediction Center Norman OK 1241 PM CDT Thu Sep 04 2025 Areas affected...parts of southwestern through north central Virginia...northwestern North Carolina Concerning...Severe potential...Watch unlikely Valid 041741Z - 041945Z Probability of Watch Issuance...20 percent SUMMARY...Developing thunderstorm activity may increasingly pose a risk for sporadic damaging wind gusts through late afternoon. This seems unlikely to require a severe weather watch, but trends are being monitored. DISCUSSION...Destabilization is ongoing to the lee of the Blue Ridge, as insolation contributes to warming within a modestly moist boundary layer with surface dew points mostly in the lower/mid 60s F. It appears that this could contribute to CAPE in excess of 1000 J/kg, within a least a narrow corridor near the pre-frontal lee surface troughing. Forcing for ascent, associated with a short wave perturbation within the moderately strong larger-scale cyclonic southwesterly mid-level flow, is in the process of spreading across and east of the higher terrain to the west. This has provided continuing support for an organized area of thunderstorm development now spreading through southwestern Virginia, and into northwestern North Carolina, with new thunderstorms beginning to initiate within the pre-frontal troughing, northeastward toward the Greater Washington D.C vicinity. A gradual further intensification of the thunderstorm activity is probable in the presence of modest deep-layer shear through mid to late afternoon. Deep-layer southwesterly mean wind fields, however, through the lower/mid-troposphere, appear a generally modest 20-30 kts. This may be sufficient, coupled with modestly steep low-level lapse rates, to support potential for sporadic damaging wind gusts, but the lack of stronger instability suggests that the overall severe threat will remain limited. ..Kerr/Gleason.. 09/04/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...LWX...RAH...RNK...GSP... LAT...LON 36218148 36858101 37288049 39097773 38417686 37657759 35838020 36218148 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

5-Day Uncertainty Track last updated Thu, 04 Sep 2025 17:42:52 GMT


Wind Speed Probabilities last updated Thu, 04 Sep 2025 15:27:22 GMT

Issued at 1100 AM MST Thu Sep 04 2025 000 WTPZ32 KNHC 041742 TCPEP2 BULLETIN Tropical Storm Lorena Intermediate Advisory Number 11A NWS National Hurricane Center Miami FL EP122025 1100 AM MST Thu Sep 04 2025 ...RISK OF LIFE-THREATENING FLASH FLOODING CONTINUES FOR BAJA CALIFORNIA SUR AND SOUTHWESTERN SONORA... SUMMARY OF 1100 AM MST...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...24.4N 114.5W ABOUT 140 MI...225 KM W OF CABO SAN LAZARO MEXICO MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...997 MB...29.44 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 Puerto Cortes to Punta Eugenia A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area. Interests elsewhere on the Baja California peninsula and in northwestern Mexico should monitor the progress of Lorena. 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 Tropical Storm Lorena was located near latitude 24.4 North, longitude 114.5 West. Lorena is moving toward the northwest near 7 mph (11 km/h). A turn toward the north and a decrease in forward speed is expected tonight. On the forecast track, the center of Lorena is expected to move generally parallel to the west coast of the Baja California peninsula through tonight, and could move closer to the west-central coast of the Baja California peninsula while it weakens on Friday. Maximum sustained winds have decreased to near 60 mph (95 km/h) with higher gusts. Lorena is expected to quickly weaken for the next couple of days, and it is forecast to degenerate into a remnant low near or to the west of the Baja California peninsula by Friday night. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 997 mb (29.44 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 Sonora Mexico through Friday. Additional rainfall totals of 4 to 8 inches, with maximum storm total amounts of 15 inches, are possible across portions of Baja California Sur, far southeast Baja California and southwestern Sonora into Friday. This will bring the risk of life-threatening flash floods and mudslides, especially in areas of higher terrain. Elsewhere across Mexico, 2 to 4 inches of rain, with isolated totals up to 6 inches, are expected across the remainder of Sonora and northern Sinaloa. These amounts will lead to isolated to scattered instances of flash flooding. Across the southwestern United States, 1 to 3 inches of rain, with isolated totals up to 5 inches, are expected across portions of Arizona and New Mexico through Saturday, bringing the potential for isolated to scattered flash flooding. For a complete depiction of forecast rainfall and flash flooding associated with Hurricane Lorena, please see the National Weather Service Storm Total Rainfall Graphic, available at hurricanes.gov/graphics_ep2.shtml?rainqpf WIND: Tropical storm conditions, mainly in gusts, are expected somewhere within the warning area in Baja California Sur today through 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

...RISK OF LIFE-THREATENING FLASH FLOODING CONTINUES FOR BAJA CALIFORNIA SUR AND SOUTHWESTERN SONORA... As of 11:00 AM MST Thu Sep 04 the center of Lorena was located near 24.4, -114.5 with movement NW at 7 mph. The minimum central pressure was 997 mb with maximum sustained winds of about 60 mph.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1226 PM CDT Thu Sep 04 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE OHIO AND TENNESSEE VALLEYS INTO THE CENTRAL APPALACHIANS... ...SUMMARY... Scattered thunderstorms capable of producing damaging wind gusts and isolated large hail are expected across parts of the Ohio and Tennessee Valleys into the Central Appalachians on Friday. ...Synopsis... A deep/vertically stacked cyclone will move gradually northward across Ontario toward Hudson Bay through the period, as an accompanying midlevel jet streak advances from the Great Lakes into Quebec. Peripheral to the deep cyclone, broad midlevel troughing will persist across much of the eastern CONUS. An accompanying cold front will extend from the Great Lakes region southwestward across the OH Valley into the southern Plains. Given the slowly evolving/amplified upper-level pattern, the cold front will only move gradually east-southeastward through the period. ...Ohio/Tennessee Valleys into the Central Appalachians... Ahead of the cold front, ample diurnal heating amid upper 60s dewpoints will contribute to a moderately unstable (around 2500 J/kg MLCAPE), uncapped pre-convective air mass. Potentially aided by a convectively augmented midlevel impulse approaching the OH Valley from the west, scattered thunderstorms should develop along/immediately ahead of the front during the afternoon into evening/overnight. The aforementioned buoyancy and around 30-40 kt of effective shear should promote convective organization into clusters/small line segments and perhaps transient supercell structures. The stronger/longer-lived storms will be capable of producing damaging wind gusts and isolated severe hail. The best overlap of moderate buoyancy (higher with southward extent) and favorable deep-layer shear (stronger with northward extent) should exist over KY and surrounding states, where a Slight Risk was added. ...Mid-South into the Southern Plains... The cold front will be oriented more west-east over this region, with the stronger deep shear confined to the cool side of the boundary. Additionally, convective initiation may occur later into the evening/overnight hours along the sharpening cold front. Nevertheless, moderate-strong buoyancy aided by steep deep-layer lapse rates will promote strong storms capable of producing locally damaging gusts and sporadic, marginally severe hail. ..Weinman.. 09/04/2025 Read more

5-Day Uncertainty Track last updated Thu, 04 Sep 2025 14:39:30 GMT


Wind Speed Probabilities last updated Thu, 04 Sep 2025 15:27:22 GMT