Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0259 PM CDT Fri Jun 21 2024 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN HIGH PLAINS TO THE UPPER MISSISSIPPI VALLEY...THE FOUR CORNERS REGION...AND SOUTHERN NEW ENGLAND... ...SUMMARY... Scattered strong to severe storms are expected from parts the upper Mississippi Valley into the northern High Plains, and into the Four Corners vicinity. A few strong storms may occur from parts of the Lower Great Lakes to southern New England. ...Discussion... Only two notable changes were made to the previous convective outlook. Otherwise the previous forecast thinking remains on track. 1) Have increased severe-wind probabilities to 15 percent and a categorical Slight Risk over southern portions of New England. Despite modest deep-layer westerly flow, steep 0-3 km lapse rates (7.5 to 8.5 deg C/km) and around 2 inches PW have yielded an environment that will favor multicells sporadically capable of strong to locally severe gusts (50-65 mph) and wind damage. A linear cluster near the NY/MA/CT border will likely push eastward over the next 2-4 hours and reach the CT/RI coast, and this area has been highlighted with recently issued Severe Thunderstorm Watch #444. 2) Included southwest NE in Slight-Risk equivalent severe wind probabilities based on the latest satellite/observational trends. Storms that potentially develop over the next few hours within southwest NE may yield a severe-wind hazard given the steep lapse rate environment. ..Smith.. 06/21/2024 .PREV DISCUSSION... /ISSUED 1052 AM CDT Fri Jun 21 2024/ ...Four Corners into WY... Water vapor imagery shows a well-defined upper trough over NV, with an associated 40+kt mid-level speed max tracking from northern AZ into UT/CO. Beneath this strengthening wind field and large-scale ascent, considerable low-level moisture is present today with dewpoints in the 50s across much eastern UT/western CO and southwest WY. Pockets of strong daytime heating will lead to scattered afternoon thunderstorms. Vertical shear profiles will promote supercell storm structures capable of hail and damaging winds for several hours this afternoon and evening. ...MT/WY... Several weak shortwave troughs are noted this morning moving east-northeastward across the northern Rockies. These features, combined with persistent easterly low-level winds across central/eastern MT will result in scattered afternoon thunderstorm development. Relatively isolated supercells are expected over MT, with more convective coverage farther south into eastern WY and western SD/NE. Storms will be capable of large hail and damaging winds, along with the possibility of a tornado or two (mainly over parts of MT). ...Central Plains... A well-defined surface boundary extends across northern NE into southern MN. Considerable heating to the south of this boundary, along with strengthening southerly low-level winds/convergence by late afternoon, will result in scattered thunderstorms in vicinity of the front. Sufficient flow aloft and ample CAPE will promote a risk of a few severe storms capable of damaging winds and hail. ...Lower MI... Pockets of strong heating will lead to scattered afternoon thunderstorms over parts of central and southern Lower MI. This area is along the southern fringe of stronger westerlies, with 25-30 knots of flow at 500mb. This might be sufficient for a few strong storms capable of gusty winds and hail. ...NY/PA/Southern New England... Hot and humid conditions are expected today across much of PA/NY and southern New England, with dewpoints in the 70s and temperatures well into the 80s and 90s. Mid level lapse rates are rather weak, so MLCAPE values will be <2000 J/kg. Given relatively weak winds aloft, thunderstorm organization is expected to be marginal. Nevertheless, a few strong storms capable of locally gusty/damaging winds are possible through the afternoon. Please refer to MCD #1352 for further details. Read more

MD 1357 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF SOUTHERN VERMONT...SOUTHERN NEW HAMPSHIRE...MASSACHUSETTS...CONNECTICUT...RHODE ISLAND
Mesoscale Discussion 1357 NWS Storm Prediction Center Norman OK 0146 PM CDT Fri Jun 21 2024 Areas affected...portions of southern Vermont...southern New Hampshire...Massachusetts...Connecticut...Rhode Island Concerning...Severe potential...Watch possible Valid 211846Z - 212015Z Probability of Watch Issuance...40 percent SUMMARY...A locally higher damaging gust threat exists across portions of New England in advance of clustering thunderstorm cells. Conditions will be monitored for the need of a WW issuance pending continued favorable trends for more damaging winds. DISCUSSION...Pulse cells and smaller multicellular clusters are attempting to organize into a loosely organized MCS in far eastern NY. Given the potential for cold pool mergers, preceded by steep low-level lapse rates, it is possible that a more organized damaging gust threat could materialize over the next few hours. 25-35 kts of effective bulk shear (whose vectors are oriented roughly normal to the long-axis of the potential MCS) may also contribute to the organization of an efficient damaging-gust-producing thunderstorm complex. Should further convective organization occur, a WW issuance eventually may be needed. ..Squitieri/Hart.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GYX...BOX...OKX...ALY... LAT...LON 42697381 43037361 43177310 43167119 42617080 42067076 41597131 41447211 41507286 41607331 42067378 42697381 Read more

WW 0442 Status Updates
STATUS REPORT ON WW 442 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..GRAMS..06/21/24 ATTN...WFO...TFX...BYZ...GGW... STATUS REPORT FOR WS 442 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC005-013-015-027-035-037-041-045-051-059-065-069-073-099-101- 107-212040- MT . MONTANA COUNTIES INCLUDED ARE BLAINE CASCADE CHOUTEAU FERGUS GLACIER GOLDEN VALLEY HILL JUDITH BASIN LIBERTY MEAGHER MUSSELSHELL PETROLEUM PONDERA TETON TOOLE WHEATLAND THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0444 Status Updates
STATUS FOR WATCH 0444 HAS NOT BEEN ISSUED YET Read more

WW 0444 Status Updates
STATUS FOR WATCH 0444 HAS NOT BEEN ISSUED YET Read more

WW 0441 Status Updates
STATUS REPORT ON WW 441 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..GRAMS..06/21/24 ATTN...WFO...GJT...ABQ...SLC...RIW... STATUS REPORT FOR WS 441 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC029-033-045-067-077-081-083-085-091-103-111-113-212040- CO . COLORADO COUNTIES INCLUDED ARE DELTA DOLORES GARFIELD LA PLATA MESA MOFFAT MONTEZUMA MONTROSE OURAY RIO BLANCO SAN JUAN SAN MIGUEL NMC006-031-045-212040- NM . NEW MEXICO COUNTIES INCLUDED ARE CIBOLA MCKINLEY SAN JUAN UTC007-009-013-015-017-019-025-031-037-039-041-047-051-055- 212040- UT . UTAH COUNTIES INCLUDED ARE CARBON DAGGETT DUCHESNE Read more

WW 0443 Status Updates
STATUS FOR WATCH 0443 HAS NOT BEEN ISSUED YET Read more

MD 1355 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF LOWER MICHIGAN INTO NORTHERN OHIO
Mesoscale Discussion 1355 NWS Storm Prediction Center Norman OK 1257 PM CDT Fri Jun 21 2024 Areas affected...portions of Lower Michigan into northern Ohio Concerning...Severe potential...Watch unlikely Valid 211757Z - 211930Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms should gradually increase in coverage and intensity through the afternoon, with the strongest storms accompanied by a couple of potentially damaging wind gusts. The severe threat should remain isolated and a WW issuance is not expected. DISCUSSION...Strong surface heating and low 70s F dewpoints beneath an upper-ridging environment is supporting convective initiation given weak MLCINH. Tropospheric lapse rates are not particularly steep, with MLCAPE constrained to around 1500 J/kg via tall and thin profiles. Vertical wind shear is weak, so mainly pulse cellular storm modes are expected. The stronger storms may produce strong wind gusts, though severe gusts should be isolated, precluding a WW issuance. ..Squitieri/Hart.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CLE...DTX...APX...IWX...GRR... LAT...LON 44228478 43808422 43578369 43898327 44018303 44018284 43708261 43058253 42618273 42098322 41818330 41588303 41378249 41048205 40718217 40938329 41598458 41848484 42538551 43558609 44118555 44228478 Read more

MD 1354 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR CENTRAL MONTANA
Mesoscale Discussion 1354 NWS Storm Prediction Center Norman OK 1235 PM CDT Fri Jun 21 2024 Areas affected...Central Montana Concerning...Severe potential...Watch likely Valid 211735Z - 211930Z Probability of Watch Issuance...80 percent SUMMARY...A WW will likely be needed for Central MT this afternoon as a few isolated supercells develop over the high terrain and move east into an environment supportive of all severe hazards. DISCUSSION...The current water vapor loop coupled with the RAP upper-air analysis shows a subtle shortwave trough/vort max approaching the Northern Rockies, with some morning convection ongoing ahead of the wave. The boundary layer south and east of the ongoing convection is characterized by mid 60s F surface temperatures and mid-to-upper 50s F dewpoints, beneath steep mid-level lapse rates of 8-9 C/km that are supportive of deep convection later this afternoon. Morning soundings and SPC Mesoanalysis indicate deep layer shear of 35-45 kts, suggesting multicellular and supercellular storm modes are likely. While ongoing convection over Judith Basin County appears to be weakening, visible satellite indicates another region of developing cumulus further to the west within a local minima of MLCINH, suggesting additional development is likely within the next few hours. RAP forecast profiles later this afternoon in Central MT indicate buoyancy will increase to 2000 J/kg MLCAPE with deep layer shear in the 45-50 kt range, suggesting a threat for supercells capable of primarily damaging wind and hail, though also supportive of tornadoes. Hodographs in South-Central MT are primarily straight-line, indicating the potential for splitting supercells capable of all hazards, while further north hodographs take on a more curved shape in the low levels, supportive of a right-moving supercell tornado threat. Overall storm coverage is uncertain at this time, but a WW will likely be needed later this afternoon for a few supercells that develop and track eastward throughout the day, capable of all hazards. ..Halbert/Weinman/Hart.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX... LAT...LON 48211193 48561099 48531030 48450901 47950766 47140682 46660674 46310690 45900747 45540820 45460896 45870988 46561058 46881100 47781190 48211193 Read more

MD 1353 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR THE FOUR CORNERS AREA TO FAR SOUTHERN WY
Mesoscale Discussion 1353 NWS Storm Prediction Center Norman OK 1210 PM CDT Fri Jun 21 2024 Areas affected...the Four Corners area to far southern WY Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 211710Z - 211915Z Probability of Watch Issuance...80 percent SUMMARY...Isolated large hail and severe wind gusts are expected this afternoon as scattered thunderstorms develop off the higher terrain of the eastern Utah/northeast Arizona vicinity and spread east-northeast. A severe thunderstorm watch will likely be issued for parts of the region by 18-19Z. DISCUSSION...Morning convection has finally weakened but has maintained a plume of cloudiness that is limiting surface-based destabilization over parts of western CO. Surrounding this remnant convection, destabilization is well underway northeast of the Mogollon Rim to the higher terrain of central UT. Incipient thunderstorm development is occurring over the higher terrain and will likely increase in coverage through the afternoon as a minor shortwave trough over NV shifts east-northeast. Relatively buoyant thermodynamic profiles are expected as MLCAPE increases to 1000-1500 J/kg at peak heating. Substantial speed shear within the deep-layer southwesterly flow regime should yield an elongated hodograph, favorable for splitting supercell structures. Large hail to around 2 inches in diameter will be possible, although potential for greater magnitudes may be tempered by relatively warm upper-level temperatures. The steepening low-level lapse rate environment will support potential for severe wind gusts of 55-70 mph, but with more cellular coverage this threat may tend to remain isolated. ..Grams/Hart.. 06/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CYS...ABQ...RIW...GJT...FGZ...SLC... LAT...LON 41640721 40720755 39030796 37040769 36260815 35791005 36601224 38431223 40001154 41880881 42040844 41640721 Read more