Severe Storms

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1236 PM CDT Tue Jul 30 2024 Valid 311200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST SD...FAR EASTERN NE...AND WESTERN IA... ...SUMMARY... Scattered strong to severe storms are possible from the Plains to the southern Great Lakes and the Appalachians to portions of New England. Highest severe potential is expected across IA Wednesday evening. ...Synopsis... Expansive upper ridging is forecast to persist across much of the southern CONUS on Wednesday, with modestly enhanced westerly flow north of this ridging across the northern CONUS. Several shortwave troughs will be embedded within this westerly flow, with the easternmost shortwave expected to progress eastward across the Northeast and Mid-Atlantic. Another shortwave trough, likely enhanced by ongoing deep convection, is forecast to move across the Upper Great Lakes and OH Valley. The most well-defined shortwave trough in the series will likely move into the northern/central Plains during the early afternoon, continuing into MN/IA late Wednesday night/early Thursday morning. General expectation is for the surface pattern Wednesday morning to be characterized by troughing across the Plains, with several embedded surface lows, and extensive ridging centered over the northwest Gulf of Mexico and covering much of the Southeast. Primary surface low attendant to the shortwave trough progressing into the northern/central Plains is expected to begin the period over the central NE/SD border vicinity before then tracking into the NE/SD/IA border region by Wednesday evening. A cold front will extend southwestward from this low, and will gradually move southeastward as the parent low moves east. Surface pattern east of the Plains into the Mid MS and OH Valleys will be complicated by the evolution of preceding thunderstorm clusters (and associated outflow) as well as by any thunderstorms generated by these shortwave troughs. Even with this uncertainty, a sharpening, warm-front-like boundary will likely extend from the low over NE/SD southeastward into southern IL, with the eastern portion over southern IL potentially modulated by ongoing storms. ...Mid MS/OH Valleys into the central/southern Appalachians Wednesday morning through the afternoon and evening... Showers and thunderstorms will likely be ongoing in the southeastern IA/northern IL/northeast MO vicinity early Wednesday morning as storms which are expected to develop across IA late Tuesday night continue southeastward. Most likely scenario is for these storms to gradually weaken throughout the morning as the low-level jet weakens and the storms become increasingly displaced eastward. However, there is a low-probability scenario where this cluster is organized enough to maintain its intensity throughout the morning. Given the low-probability and general forecast uncertainty, only Marginal/5% wind probabilities will be maintained for this region with this outlook. Additional thunderstorm development is anticipated downstream from the upper OH Valley into the central and southern Appalachians as the remnants from the early morning storms move into a moist, and diurnally destabilized airmass. Shear will be weak, with a multicellular, pulse mode anticipated. Damaging gusts will be the primary severe risk. ...Upper Midwest/Mid MS Valley into the central/southern Plains... Southerly flow will continue to advect ample low-level moisture into the warm sector ahead of the cold front associated with the shortwave trough moving into the northern/central Plains, with low 70s dewpoints likely reaching southern MN by early Wednesday afternoon. Robust heating amid this high low-level moisture will support airmass destabilization and very strong buoyancy, with over 3000 J/kg of MLCAPE throughout much of the warm sector. Thunderstorm development is expected to begin across SD and MN during the afternoon, with the environmental conditions supporting strong to severe storms. Large to very large hail is possible initially, particularly across eastern SD and southern MN where buoyancy is highest. Thunderstorm development is then expected to expand southwestward along the front, from SD into KS (potentially even the TX/OK Panhandles). A more outflow-dominant storm character is anticipated with southern extend as weaker shear preclude updraft organization. Organization into a forward-propagating MCS appears likely Wednesday evening, with the potential for significant-severe gusts stretching into IA. This MCS will likely still be ongoing early Thursday morning across IL, although the strength and organization of the MCS at that time is uncertain. Enough buoyancy should still be in place to support severe if the MCS remains organized. ..Mosier.. 07/30/2024 Read more

WW 0568 Status Updates
STATUS REPORT ON WW 568 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 W LWD TO 35 SSE OTM TO 40 NW BRL. ..LEITMAN..07/30/24 ATTN...WFO...DMX...DVN...LSX...EAX... STATUS REPORT FOR WS 568 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-067-149-301840- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN HANCOCK PIKE IAC111-177-301840- IA . IOWA COUNTIES INCLUDED ARE LEE VAN BUREN MOC001-007-041-045-079-081-103-111-115-121-127-129-137-163-171- 173-175-197-199-205-211-301840- MO . MISSOURI COUNTIES INCLUDED ARE ADAIR AUDRAIN CHARITON CLARK GRUNDY HARRISON Read more

WW 0568 Status Updates
STATUS REPORT ON WW 568 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 W LWD TO 35 SSE OTM TO 40 NW BRL. ..LEITMAN..07/30/24 ATTN...WFO...DMX...DVN...LSX...EAX... STATUS REPORT FOR WS 568 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ILC001-009-067-149-301840- IL . ILLINOIS COUNTIES INCLUDED ARE ADAMS BROWN HANCOCK PIKE IAC111-177-301840- IA . IOWA COUNTIES INCLUDED ARE LEE VAN BUREN MOC001-007-041-045-079-081-103-111-115-121-127-129-137-163-171- 173-175-197-199-205-211-301840- MO . MISSOURI COUNTIES INCLUDED ARE ADAIR AUDRAIN CHARITON CLARK GRUNDY HARRISON Read more

WW 0569 Status Updates
STATUS REPORT ON WW 569 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW EVV TO 40 NE EVV TO 15 ESE BMG. ..LEITMAN..07/30/24 ATTN...WFO...LMK...IND...PAH... STATUS REPORT FOR WS 569 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS INC019-025-037-043-061-093-117-123-129-143-147-163-173-175- 301740- IN . INDIANA COUNTIES INCLUDED ARE CLARK CRAWFORD DUBOIS FLOYD HARRISON LAWRENCE ORANGE PERRY POSEY SCOTT SPENCER VANDERBURGH WARRICK WASHINGTON KYC027-029-059-093-101-103-111-123-163-179-185-211-215-223- 301740- KY . KENTUCKY COUNTIES INCLUDED ARE BRECKINRIDGE BULLITT DAVIESS HARDIN HENDERSON HENRY JEFFERSON LARUE MEADE NELSON OLDHAM SHELBY SPENCER TRIMBLE Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Tue Jul 30 2024 Valid 301630Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE MID MISSISSIPPI VALLEY/MIDWEST... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Severe thunderstorms are expected today into tonight across a broad area from eastern Nebraska and Iowa into parts of the Midwest, Tennessee Valley and southern Appalachians, with multiple swaths of damaging winds likely within this corridor. Severe thunderstorms are also possible across parts of the northern Plains. ...Mid Missouri Valley into the Midwest/Ohio Valley/Southeast... A larger than usual amount of uncertainty remains regarding convective evolution this afternoon though tonight. Ongoing cluster in southern IA will move southeastward across the mid MS Valley into a rapidly destabilizing airmass with enhanced northwesterly winds at mid/upper-levels supporting sufficient deep-layer shear for continued updraft organization. A swath of severe/damaging winds appears likely with this cluster given the favorable parameter space. Therefore, the Enhanced Risk for damaging winds has been extended southeastward to account for the forecast evolution of this MCS. Another ongoing cluster over the lower OH Valley should also pose some threat for severe/damaging winds as it and associated outflow on its southwest flank spreads east-southeastward across KY and perhaps parts of TN the rest of this afternoon/evening. Additional robust thunderstorm development appears possible through the period in a broad corridor from central/eastern NE through the lower OH Valley and Southeast, with swaths of damaging winds likely the main threat. Details on where/when this activity will develop remain rather uncertain. But, isolated supercells may develop across central/eastern NE late this afternoon/evening in the vicinity of a surface low/lee trough. Very large hail may occur with this convection, with a greater threat for severe/damaging winds possible if this activity can grow upscale into another cluster and spread southeastward across the mid MO and mid MS Valleys this evening/overnight. ...Northern Plains... Weak mid-level height falls amid moderate to strong instability should foster to widely scattered thunderstorm development along a surface trough/dryline across parts of the Dakotas this afternoon. Moderate mid-level westerlies should support deep-layer shear around 30-35 kt, sufficient for a few organized storms, including a few supercells, capable of both large hail and damaging gusts this afternoon and evening. ...Mid-Atlantic Vicinity... A weak mid/upper-level trough and will move across the Mid-Atlantic and vicinity through this evening. Scattered thunderstorm development should continue this afternoon from VA into parts of PA. While there is some uncertainty regarding the extent of heating and destabilization due to lingering cloudiness, a couple of stronger cells/clusters may become capable of producing isolated damaging winds. ...Northeast... Weak to locally moderate instability may develop this afternoon from parts of northern New York into northern New England. While storm coverage remains uncertain, deep-layer shear and relatively cool temperatures aloft could support a couple of modestly organized thunderstorms capable of locally damaging winds, and possibly some hail. ..Gleason/Moore.. 07/30/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Tue Jul 30 2024 Valid 301630Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE MID MISSISSIPPI VALLEY/MIDWEST... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Severe thunderstorms are expected today into tonight across a broad area from eastern Nebraska and Iowa into parts of the Midwest, Tennessee Valley and southern Appalachians, with multiple swaths of damaging winds likely within this corridor. Severe thunderstorms are also possible across parts of the northern Plains. ...Mid Missouri Valley into the Midwest/Ohio Valley/Southeast... A larger than usual amount of uncertainty remains regarding convective evolution this afternoon though tonight. Ongoing cluster in southern IA will move southeastward across the mid MS Valley into a rapidly destabilizing airmass with enhanced northwesterly winds at mid/upper-levels supporting sufficient deep-layer shear for continued updraft organization. A swath of severe/damaging winds appears likely with this cluster given the favorable parameter space. Therefore, the Enhanced Risk for damaging winds has been extended southeastward to account for the forecast evolution of this MCS. Another ongoing cluster over the lower OH Valley should also pose some threat for severe/damaging winds as it and associated outflow on its southwest flank spreads east-southeastward across KY and perhaps parts of TN the rest of this afternoon/evening. Additional robust thunderstorm development appears possible through the period in a broad corridor from central/eastern NE through the lower OH Valley and Southeast, with swaths of damaging winds likely the main threat. Details on where/when this activity will develop remain rather uncertain. But, isolated supercells may develop across central/eastern NE late this afternoon/evening in the vicinity of a surface low/lee trough. Very large hail may occur with this convection, with a greater threat for severe/damaging winds possible if this activity can grow upscale into another cluster and spread southeastward across the mid MO and mid MS Valleys this evening/overnight. ...Northern Plains... Weak mid-level height falls amid moderate to strong instability should foster to widely scattered thunderstorm development along a surface trough/dryline across parts of the Dakotas this afternoon. Moderate mid-level westerlies should support deep-layer shear around 30-35 kt, sufficient for a few organized storms, including a few supercells, capable of both large hail and damaging gusts this afternoon and evening. ...Mid-Atlantic Vicinity... A weak mid/upper-level trough and will move across the Mid-Atlantic and vicinity through this evening. Scattered thunderstorm development should continue this afternoon from VA into parts of PA. While there is some uncertainty regarding the extent of heating and destabilization due to lingering cloudiness, a couple of stronger cells/clusters may become capable of producing isolated damaging winds. ...Northeast... Weak to locally moderate instability may develop this afternoon from parts of northern New York into northern New England. While storm coverage remains uncertain, deep-layer shear and relatively cool temperatures aloft could support a couple of modestly organized thunderstorms capable of locally damaging winds, and possibly some hail. ..Gleason/Moore.. 07/30/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Tue Jul 30 2024 Valid 301630Z - 311200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE MID MISSISSIPPI VALLEY/MIDWEST... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Severe thunderstorms are expected today into tonight across a broad area from eastern Nebraska and Iowa into parts of the Midwest, Tennessee Valley and southern Appalachians, with multiple swaths of damaging winds likely within this corridor. Severe thunderstorms are also possible across parts of the northern Plains. ...Mid Missouri Valley into the Midwest/Ohio Valley/Southeast... A larger than usual amount of uncertainty remains regarding convective evolution this afternoon though tonight. Ongoing cluster in southern IA will move southeastward across the mid MS Valley into a rapidly destabilizing airmass with enhanced northwesterly winds at mid/upper-levels supporting sufficient deep-layer shear for continued updraft organization. A swath of severe/damaging winds appears likely with this cluster given the favorable parameter space. Therefore, the Enhanced Risk for damaging winds has been extended southeastward to account for the forecast evolution of this MCS. Another ongoing cluster over the lower OH Valley should also pose some threat for severe/damaging winds as it and associated outflow on its southwest flank spreads east-southeastward across KY and perhaps parts of TN the rest of this afternoon/evening. Additional robust thunderstorm development appears possible through the period in a broad corridor from central/eastern NE through the lower OH Valley and Southeast, with swaths of damaging winds likely the main threat. Details on where/when this activity will develop remain rather uncertain. But, isolated supercells may develop across central/eastern NE late this afternoon/evening in the vicinity of a surface low/lee trough. Very large hail may occur with this convection, with a greater threat for severe/damaging winds possible if this activity can grow upscale into another cluster and spread southeastward across the mid MO and mid MS Valleys this evening/overnight. ...Northern Plains... Weak mid-level height falls amid moderate to strong instability should foster to widely scattered thunderstorm development along a surface trough/dryline across parts of the Dakotas this afternoon. Moderate mid-level westerlies should support deep-layer shear around 30-35 kt, sufficient for a few organized storms, including a few supercells, capable of both large hail and damaging gusts this afternoon and evening. ...Mid-Atlantic Vicinity... A weak mid/upper-level trough and will move across the Mid-Atlantic and vicinity through this evening. Scattered thunderstorm development should continue this afternoon from VA into parts of PA. While there is some uncertainty regarding the extent of heating and destabilization due to lingering cloudiness, a couple of stronger cells/clusters may become capable of producing isolated damaging winds. ...Northeast... Weak to locally moderate instability may develop this afternoon from parts of northern New York into northern New England. While storm coverage remains uncertain, deep-layer shear and relatively cool temperatures aloft could support a couple of modestly organized thunderstorms capable of locally damaging winds, and possibly some hail. ..Gleason/Moore.. 07/30/2024 Read more