Aggregator

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0332 PM CDT Fri Aug 09 2024 Valid 111200Z - 171200Z Fire weather concerns will primarily remain focused across portions of the Great Basin through the extended period. Long-range ensemble guidance shows reasonably good agreement the gradual amplification of the upper-level synoptic regime over the next seven days. This will be characterized by ridging across the central CONUS with mean troughing along the West Coast. West/southwesterly flow over the Great Basin will allow multiple short-wave disturbances to propagate across the West with frequent rain/thunderstorm chances across the Four Corners amid a continued northward flux of monsoonal moisture from the Gulf of California. However, ensemble guidance suggest predominantly dry conditions will persist across NV, CA, and southeast OR/southwest ID. This will maintain dry fuels as winds increase with each passing upper disturbance. Some solutions (notably recent GFS and GEFS runs) suggest localized elevated conditions will be possible each day across southern CA into much of NV, though confidence in somewhat more widespread elevated conditions (with perhaps some critical conditions) remains highest on D4/Monday when a progressive shortwave moves across the region. ..Moore.. 08/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0332 PM CDT Fri Aug 09 2024 Valid 111200Z - 171200Z Fire weather concerns will primarily remain focused across portions of the Great Basin through the extended period. Long-range ensemble guidance shows reasonably good agreement the gradual amplification of the upper-level synoptic regime over the next seven days. This will be characterized by ridging across the central CONUS with mean troughing along the West Coast. West/southwesterly flow over the Great Basin will allow multiple short-wave disturbances to propagate across the West with frequent rain/thunderstorm chances across the Four Corners amid a continued northward flux of monsoonal moisture from the Gulf of California. However, ensemble guidance suggest predominantly dry conditions will persist across NV, CA, and southeast OR/southwest ID. This will maintain dry fuels as winds increase with each passing upper disturbance. Some solutions (notably recent GFS and GEFS runs) suggest localized elevated conditions will be possible each day across southern CA into much of NV, though confidence in somewhat more widespread elevated conditions (with perhaps some critical conditions) remains highest on D4/Monday when a progressive shortwave moves across the region. ..Moore.. 08/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0332 PM CDT Fri Aug 09 2024 Valid 111200Z - 171200Z Fire weather concerns will primarily remain focused across portions of the Great Basin through the extended period. Long-range ensemble guidance shows reasonably good agreement the gradual amplification of the upper-level synoptic regime over the next seven days. This will be characterized by ridging across the central CONUS with mean troughing along the West Coast. West/southwesterly flow over the Great Basin will allow multiple short-wave disturbances to propagate across the West with frequent rain/thunderstorm chances across the Four Corners amid a continued northward flux of monsoonal moisture from the Gulf of California. However, ensemble guidance suggest predominantly dry conditions will persist across NV, CA, and southeast OR/southwest ID. This will maintain dry fuels as winds increase with each passing upper disturbance. Some solutions (notably recent GFS and GEFS runs) suggest localized elevated conditions will be possible each day across southern CA into much of NV, though confidence in somewhat more widespread elevated conditions (with perhaps some critical conditions) remains highest on D4/Monday when a progressive shortwave moves across the region. ..Moore.. 08/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0332 PM CDT Fri Aug 09 2024 Valid 111200Z - 171200Z Fire weather concerns will primarily remain focused across portions of the Great Basin through the extended period. Long-range ensemble guidance shows reasonably good agreement the gradual amplification of the upper-level synoptic regime over the next seven days. This will be characterized by ridging across the central CONUS with mean troughing along the West Coast. West/southwesterly flow over the Great Basin will allow multiple short-wave disturbances to propagate across the West with frequent rain/thunderstorm chances across the Four Corners amid a continued northward flux of monsoonal moisture from the Gulf of California. However, ensemble guidance suggest predominantly dry conditions will persist across NV, CA, and southeast OR/southwest ID. This will maintain dry fuels as winds increase with each passing upper disturbance. Some solutions (notably recent GFS and GEFS runs) suggest localized elevated conditions will be possible each day across southern CA into much of NV, though confidence in somewhat more widespread elevated conditions (with perhaps some critical conditions) remains highest on D4/Monday when a progressive shortwave moves across the region. ..Moore.. 08/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0332 PM CDT Fri Aug 09 2024 Valid 111200Z - 171200Z Fire weather concerns will primarily remain focused across portions of the Great Basin through the extended period. Long-range ensemble guidance shows reasonably good agreement the gradual amplification of the upper-level synoptic regime over the next seven days. This will be characterized by ridging across the central CONUS with mean troughing along the West Coast. West/southwesterly flow over the Great Basin will allow multiple short-wave disturbances to propagate across the West with frequent rain/thunderstorm chances across the Four Corners amid a continued northward flux of monsoonal moisture from the Gulf of California. However, ensemble guidance suggest predominantly dry conditions will persist across NV, CA, and southeast OR/southwest ID. This will maintain dry fuels as winds increase with each passing upper disturbance. Some solutions (notably recent GFS and GEFS runs) suggest localized elevated conditions will be possible each day across southern CA into much of NV, though confidence in somewhat more widespread elevated conditions (with perhaps some critical conditions) remains highest on D4/Monday when a progressive shortwave moves across the region. ..Moore.. 08/09/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Fri Aug 09 2024 Valid 092000Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR EASTERN PA INTO NJ...EASTERN NY...AND WESTERN NEW ENGLAND... ...SUMMARY... A couple of tornadoes will be possible today from parts of the Mid-Atlantic states northward across portions of New England. A few strong wind gusts will also be possible across this region, along with parts of the southern High Plains, and southern Wyoming. ...20Z Update... Overall forecast reasoning remains valid. Post-TC Debby continues to progress northeastward across New York, with a band of deeper convection extending from just east of its center southward into far eastern PA/far western NJ. Area VADs show strong wind fields throughout the eastern portion of this cyclone, but limited buoyancy has tempered storm depth and persistence thus far. Given the robust wind fields, the potential for damaging gusts and/or brief tornadoes will persist throughout the afternoon and into the evening, particularly in areas ahead of the main convective line where more cellular storms are likely. Farther west, afternoon/evening thunderstorms are still possible across the higher terrain of WY, CO, and NM, with these storms then moving into the central/southern High Plains thereafter. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts. ..Mosier.. 08/09/2024 .PREV DISCUSSION... /ISSUED 1140 AM CDT Fri Aug 09 2024/ ...Portions of the Mid-Atlantic and New England... As the center of P.T.C. Debby -- now over south-central New York -- continues moving north-northeastward across New York today, and then into Quebec/across the St. Lawrence Valley this evening and tonight, very strong low-level shear will continue to spread northward across eastern New York and much of New England. While northward destabilization will be hindered by a lack of appreciable daytime heating due to widespread cloud cover, a very moist boundary layer (dewpoints in the upper 60s to low 70s) spreading northward toward the Canadian border will support at least neutrally buoyant profiles across most of New England this evening and tonight. As such, low (2%) tornado probability is being expanded northward/northeastward in this update, to include the remainder of northern Vermont and northern New Hampshire, and much of Maine, to cover the potential for a brief tornadic spin-up after dark. Otherwise, greatest potential for a couple of tornadoes will exist this afternoon and into this evening from eastern Pennsylvania/eastern New York into parts of New Jersey, and across the Hudson and Champlain Valleys into western Vermont, western Massachusetts, and western Connecticut. ...Southern High Plains... Afternoon storm development is expected across the Raton Mesa vicinity of northeastern New Mexico, aided by afternoon heating/destabilization, and the eastward advance of a mid-level vort max across southern Colorado. Moderate (around 30 kt) mid-level westerlies may support some organization/upscale growth of storms into the evening, along with accompanying potential for a couple of strong gusts as convection crosses the Oklahoma and northern Texas Panhandle area. ...Southern Wyoming... Daytime heating/modest destabilization across the Intermountain West will support development of isolated to scattered afternoon and evening thunderstorms. With a belt of moderate (30 to 40 kt) northwesterly flow across the Wyoming vicinity, some storm organization will be possible. Some CAMs suggest eventual upscale growth into a loosely organized cluster by this evening, moving east-southeastward toward southeastern portions of the state. Resulting potential for a few stronger wind gusts with this activity warrants inclusion of 5% wind probability/MRGL risk area. Read more

WW 0617 Status Updates
STATUS REPORT ON WW 617 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SSW ABE TO 30 SSW MSV TO 15 S SLK. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1874 ..WEINMAN..08/09/24 ATTN...WFO...BOX...ALY...OKX...PHI...BGM...BTV... STATUS REPORT FOR WT 617 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC003-005-092040- CT . CONNECTICUT COUNTIES INCLUDED ARE HARTFORD LITCHFIELD MAC003-011-013-015-092040- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BERKSHIRE FRANKLIN HAMPDEN HAMPSHIRE NJC003-013-019-021-023-027-031-035-037-039-041-092040- NJ . NEW JERSEY COUNTIES INCLUDED ARE BERGEN ESSEX HUNTERDON Read more

MD 1874 CONCERNING TORNADO WATCH 617... FOR PORTIONS OF SOUTHEASTERN NY...WESTERN MA...AND SOUTHERN VT
Mesoscale Discussion 1874 NWS Storm Prediction Center Norman OK 0127 PM CDT Fri Aug 09 2024 Areas affected...Portions of southeastern NY...western MA...and southern VT Concerning...Tornado Watch 617... Valid 091827Z - 092000Z The severe weather threat for Tornado Watch 617 continues. SUMMARY...Within Tornado Watch 617, a potentially favorable corridor for a couple tornadoes is evident from southeastern NY into western MA and southern VT this afternoon. DISCUSSION...Latest visible satellite imagery indicates filtered diurnal heating (temperatures climbing into the upper 70s/lower 80s) within small cloud breaks in the vicinity of an east/west-oriented warm front moving slowly northward across southeastern NY to near MA and VT. Given the high-PW/tropical airmass in place, this heating may yield sufficient (albeit weak) MLCAPE for a couple low-topped, surface-based showers/storms this afternoon. Any convection that can root in the boundary layer may evolve into low-topped supercells, aided by strong deep-layer flow/shear associated with Post-Tropical Cyclone Debby. Additionally, the aforementioned corridor will be located beneath the core of a northward-advancing low-level jet during peak heating -- on the eastern periphery of the most substantial surface-pressure falls. Here, large, clockwise-curved/sickle-shaped hodographs (around 400 m2/s2 0-500m SRH per KENX VWP), will conditionally support a couple tornadoes with the more robust surface-based convection. ..Weinman.. 08/09/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...ALY...BGM... LAT...LON 42657438 42987395 43107341 43057259 42917233 42607233 41887396 41987435 42327450 42657438 Read more

WW 0617 Status Updates
STATUS REPORT ON WW 617 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1874 ..WEINMAN..08/09/24 ATTN...WFO...BOX...ALY...OKX...PHI...BGM...BTV... STATUS REPORT FOR WT 617 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC003-005-091940- CT . CONNECTICUT COUNTIES INCLUDED ARE HARTFORD LITCHFIELD MAC003-011-013-015-091940- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BERKSHIRE FRANKLIN HAMPDEN HAMPSHIRE NJC003-013-019-021-023-027-031-035-037-039-041-091940- NJ . NEW JERSEY COUNTIES INCLUDED ARE BERGEN ESSEX HUNTERDON MERCER MIDDLESEX MORRIS Read more

WW 0617 Status Updates
STATUS REPORT ON WW 617 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1874 ..WEINMAN..08/09/24 ATTN...WFO...BOX...ALY...OKX...PHI...BGM...BTV... STATUS REPORT FOR WT 617 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS CTC003-005-091940- CT . CONNECTICUT COUNTIES INCLUDED ARE HARTFORD LITCHFIELD MAC003-011-013-015-091940- MA . MASSACHUSETTS COUNTIES INCLUDED ARE BERKSHIRE FRANKLIN HAMPDEN HAMPSHIRE NJC003-013-019-021-023-027-031-035-037-039-041-091940- NJ . NEW JERSEY COUNTIES INCLUDED ARE BERGEN ESSEX HUNTERDON MERCER MIDDLESEX MORRIS Read more