SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

1 year ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1140 AM CDT Sat Aug 31 2024 Valid 311700Z - 011200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/31/2024 .PREV DISCUSSION... /ISSUED 1242 AM CDT Sat Aug 31 2024/ ...Synopsis... Dry thunderstorms will be the primary fire weather concern for today across portions of southern/eastern Nevada into far southwest Utah. A modest monsoonal moisture plume has been slowly spreading northwestward from southern/central AZ into southern NV over the past 12 hours per GOES water-vapor and PWAT imagery. Increasing mid-level moisture has also been noted in recent VEF soundings with PWAT values increasing to 0.85 inches as recently as 00 UTC Saturday. This moisture, combined with cool mid-level temperatures, will support isolated thunderstorms by late afternoon as ascent associated with a weak mid-level perturbation overspreads the southern Great Basin. Slow storm motions around 10 knots should promote very narrow swaths of rainfall, but very dry boundary layer conditions (similar in nature to the 00 UTC VEF sounding) will likely be in place by peak heating and should promote limited rain accumulation away from the primary downdraft cores. While thunderstorm coverage is expected to be fairly isolated, dry lightning strikes are likely with any storm that can develop and will pose a fire weather concern considering ERCs are at or above the 80th percentile. Elsewhere, very dry conditions will persist across the remainder of the Great Basin with afternoon RH values in the single digits to teens. Surface gradient winds are forecast to generally remain below 15 mph for most locations, which limits confidence in additional fire weather concerns. The general consensus among recent high-res guidance is that the strongest winds will likely be associated with thunderstorm outflows across southern NV/southwest UT and into central AZ. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1630 UTC Day 1 Convective Outlook

1 year ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Sat Aug 31 2024 Valid 311630Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will move eastward across Ontario/Quebec and the Great Lakes today while undergoing some amplification. Ahead of this feature, a surface front will move eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. A warm front will lift north through the period across the mid-Atlantic and northeast states. Late morning visible satellite imagery shows substantial low cloud cover over much of the Northeast and Mid-Atlantic. This will reduce daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. However, with a moist low-level air mass in place, even modest diurnal heating will result in sufficient destabilization to support some risk for strong/severe storms. The stronger mid-level flow associated with the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop or intensify and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cells. Storms should gradually weaken with eastward extent by this evening across the Mid-Atlantic while encountering a less unstable air mass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. However, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will exist over the Upper Midwest and northern Great Lakes in association with a shortwave trough embedded within a broader cyclonic flow. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development of low-topped thunderstorms this afternoon. If these thunderstorms can be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow in the presence of steepened low-level lapse rates. ..Bunting/Jewell.. 08/31/2024 Read more

SPC Aug 31, 2024 1300 UTC Day 1 Convective Outlook

1 year ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 AM CDT Sat Aug 31 2024 Valid 311300Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL APPALACHIANS AND UPPER OHIO VALLEY... ...SUMMARY... Severe thunderstorms capable of producing mainly damaging winds will be possible today from parts of the central Appalachians into the Ohio and Tennessee Valleys. Isolated severe wind gusts may also occur across parts of the northern Great Lakes. ...Mid-Atlantic into the Ohio and Tennessee Valleys... A mid/upper-level trough will make slow eastward progress today across Ontario/Quebec and the Great Lakes while amplifying further. Ahead of this feature, a surface front should continue to lose definition and weaken through the day as it moves eastward over parts of the Northeast/Mid-Atlantic, and southeastward over the OH Valley before eventually stalling. Recent visible satellite imagery shows cloud cover remains prevalent over much of the Northeast and Mid-Atlantic. This will hinder daytime heating and delay destabilization, especially east of the Blue Ridge Mountains. Still, area 12Z soundings and recent surface observations indicate a moist low-level airmass remains in place ahead of the weak cold front. Generally less cloud cover with westward and southward extent into the upper OH Valley and TN Valley should allow for greater instability to develop this afternoon across these regions. The stronger mid-level flow associated the upper trough is expected to remain generally displaced to the north/west of the surface warm sector. Even so, modestly increasing west-southwesterly winds with height through mid levels should support around 20-30 kt of deep-layer shear across parts of the central Appalachians and upper OH Valley vicinity. This shear will be sufficient for loosely organized multicell clusters to develop and subsequently spread east-southeastward through this afternoon. Isolated to scattered damaging winds should be the main threat with this convection, although some hail may also occur with the strongest cores. Activity should weaken with eastward extent late this afternoon and evening across the Mid-Atlantic as it encounters a less unstable airmass. Weaker deep-layer shear with southward extent into the lower OH Valley and TN Valley will likely limit overall thunderstorm organization. But, occasional damaging winds may still occur with thunderstorms along/south of the front as low-level lapse rates steepen with diurnal heating. ...Northern Great Lakes... Strong west-northwesterly mid-level flow will be present today over the Upper Midwest and northern Great Lakes, in association with a shortwave trough embedded within a larger upper trough moving east-southeastward across these regions. While low-level moisture and related instability are both expected to remain limited, large-scale ascent and strong deep-layer shear may support the development low-topped convection this afternoon. If these thunderstorms can form and be sustained, then isolated strong to severe winds may occur given the forecast strength of the low to mid-level flow amid steepened low-level lapse rates. ..Gleason/Leitman.. 08/31/2024 Read more