Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Fri Aug 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms currently appears negligible across much of the U.S. for Sunday through Sunday night. ...Discussion... It appears that mid-level flow across the northern mid-latitudes will remain amplified through this period, with a prominent mid-level high continuing to evolve over the Canadian Yukon Territory vicinity Sunday through Sunday night. Downstream, seasonably strong cyclonic flow likely will be maintained across the upper Great Lakes vicinity through the St. Lawrence Valley, to the south of a prominent cyclone slowly shifting eastward across northern Quebec. In lower latitudes, a prominent high is forecast to remain centered across the Four Corners vicinity, with ridging building along an axis to its east, across the southern Rockies into the central Great Plains. Within modest westerly flow on the northern periphery of this ridging, low-amplitude troughing may progress across and east-southeast of the northern Rockies into the Dakotas. However, it appears that associated forcing for ascent will generally lag to the cool side of a notable preceding surface cold front, which may advance south and west of the Black Hills and through much of the northern Great Plains and Upper Midwest by 12Z Sunday. Beneath a plume of warm elevated mixed-layer air, models indicate that large potential boundary-layer instability may develop in a pre-frontal corridor with daytime heating, probably across parts of Nebraska and Iowa through southern Wisconsin/northern Illinois into southern Lower Michigan by late Sunday afternoon. If forcing for ascent becomes sufficient to support thunderstorm development within this environment, forecast thermodynamic profiles appear conducive to a risk for severe hail and wind in stronger storms. However, it currently appears that any such activity may remain very isolated in nature, with uncertainty in location and low coverage precluding introduction of 5 percent severe probabilities. Uncertainties also remain large concerning the tropical perturbation emerging from the Caribbean, and its evolution near/west of the Florida Gulf coast Sunday through Sunday night. At this point, the risk for severe weather still appears low, but this could quickly and substantively change, and trends will need to be monitored. ..Kerr.. 08/02/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Fri Aug 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms currently appears negligible across much of the U.S. for Sunday through Sunday night. ...Discussion... It appears that mid-level flow across the northern mid-latitudes will remain amplified through this period, with a prominent mid-level high continuing to evolve over the Canadian Yukon Territory vicinity Sunday through Sunday night. Downstream, seasonably strong cyclonic flow likely will be maintained across the upper Great Lakes vicinity through the St. Lawrence Valley, to the south of a prominent cyclone slowly shifting eastward across northern Quebec. In lower latitudes, a prominent high is forecast to remain centered across the Four Corners vicinity, with ridging building along an axis to its east, across the southern Rockies into the central Great Plains. Within modest westerly flow on the northern periphery of this ridging, low-amplitude troughing may progress across and east-southeast of the northern Rockies into the Dakotas. However, it appears that associated forcing for ascent will generally lag to the cool side of a notable preceding surface cold front, which may advance south and west of the Black Hills and through much of the northern Great Plains and Upper Midwest by 12Z Sunday. Beneath a plume of warm elevated mixed-layer air, models indicate that large potential boundary-layer instability may develop in a pre-frontal corridor with daytime heating, probably across parts of Nebraska and Iowa through southern Wisconsin/northern Illinois into southern Lower Michigan by late Sunday afternoon. If forcing for ascent becomes sufficient to support thunderstorm development within this environment, forecast thermodynamic profiles appear conducive to a risk for severe hail and wind in stronger storms. However, it currently appears that any such activity may remain very isolated in nature, with uncertainty in location and low coverage precluding introduction of 5 percent severe probabilities. Uncertainties also remain large concerning the tropical perturbation emerging from the Caribbean, and its evolution near/west of the Florida Gulf coast Sunday through Sunday night. At this point, the risk for severe weather still appears low, but this could quickly and substantively change, and trends will need to be monitored. ..Kerr.. 08/02/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Fri Aug 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms currently appears negligible across much of the U.S. for Sunday through Sunday night. ...Discussion... It appears that mid-level flow across the northern mid-latitudes will remain amplified through this period, with a prominent mid-level high continuing to evolve over the Canadian Yukon Territory vicinity Sunday through Sunday night. Downstream, seasonably strong cyclonic flow likely will be maintained across the upper Great Lakes vicinity through the St. Lawrence Valley, to the south of a prominent cyclone slowly shifting eastward across northern Quebec. In lower latitudes, a prominent high is forecast to remain centered across the Four Corners vicinity, with ridging building along an axis to its east, across the southern Rockies into the central Great Plains. Within modest westerly flow on the northern periphery of this ridging, low-amplitude troughing may progress across and east-southeast of the northern Rockies into the Dakotas. However, it appears that associated forcing for ascent will generally lag to the cool side of a notable preceding surface cold front, which may advance south and west of the Black Hills and through much of the northern Great Plains and Upper Midwest by 12Z Sunday. Beneath a plume of warm elevated mixed-layer air, models indicate that large potential boundary-layer instability may develop in a pre-frontal corridor with daytime heating, probably across parts of Nebraska and Iowa through southern Wisconsin/northern Illinois into southern Lower Michigan by late Sunday afternoon. If forcing for ascent becomes sufficient to support thunderstorm development within this environment, forecast thermodynamic profiles appear conducive to a risk for severe hail and wind in stronger storms. However, it currently appears that any such activity may remain very isolated in nature, with uncertainty in location and low coverage precluding introduction of 5 percent severe probabilities. Uncertainties also remain large concerning the tropical perturbation emerging from the Caribbean, and its evolution near/west of the Florida Gulf coast Sunday through Sunday night. At this point, the risk for severe weather still appears low, but this could quickly and substantively change, and trends will need to be monitored. ..Kerr.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Aug 02 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN SOUTH DAKOTA INTO WESTERN MINNESOTA...AND FAR NORTHWEST IOWA... ...SUMMARY... Scattered severe storms are most likely Saturday afternoon and evening from eastern South Dakota into Minnesota with damaging winds and hail possible. Scattered thunderstorms with a low risk of damaging gusts may impact the Southeastern Piedmont and adjacent portions of the coastal plain into northern Mid Atlantic Saturday afternoon and evening. A developing tropical cyclone may also impact the Florida Keys and western Florida Peninsula. ...Synopsis... A slow-moving positive-tilt upper trough will affect much of the Northeast and Mid Atlantic on Saturday, providing minor cooling aloft and modest southwest flow. A weak front will stretch from parts of New England southward into northern GA, with a moist air pass to the east with 70s F dewpoints. To the west, moderate northwest flow aloft will exist across the northern Plains and upper MS Valley, on the southern periphery of a large Hudson Bay low. A surface low is expected over SD ahead of a cold front which will stretch roughly from the Black Hills into northern MN, with pockets of moisture aiding destabilization. Meanwhile, a disturbance now over Cuba is expected to become a Tropical Storm as it crosses the Florida Straits and turns northward into Sunday morning, per latest NHC guidance. ...Northern Plains and Upper MS Valley... Storms are likely to form along the cold front near 21Z from northern SD into north-central MN, with an increase in coverage and intensity through early evening. Moderate instability and favorable northwest flow aloft will favor large hail with the initial activity, with small cluster or perhaps an MCS producing damaging winds as outflow surges southward across eastern SD, southwest MN, and northwest IA. As such, the area has been upgraded to Slight Risk. ...Eastern States... Scattered storms will develop by early afternoon along the length of the front, within the very moist and heating air mass. Lapse rates aloft will be poor, and shear weak, but sporadic strong or damaging outflows/gusts will be possible within this large zone through early evening before the air mass is completely overturned and stabilized. ...FL Peninsula and Keys... Per latest NHC guidance, a Tropical Storm is expected to impact the region late Saturday and through the end of the Day 2 period. A very moist/tropical air mass will exist along and east of the center track, and a general increase in low-level shear is anticipated. As such, brief circulations may eventually develop with any of the stronger cells within eastern convective bands as they proceed across the Keys and the western FL Peninsula. A 2% tornado probability has been added for this possibility. ..Jewell.. 08/02/2024 Read more

No Mesoscale Discussions are in effect as of Fri Aug 2 17:33:02 UTC 2024.

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Fri Aug 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms currently appears negligible across much of the U.S. for Sunday through Sunday night. ...Discussion... It appears that mid-level flow across the northern mid-latitudes will remain amplified through this period, with a prominent mid-level high continuing to evolve over the Canadian Yukon Territory vicinity Sunday through Sunday night. Downstream, seasonably strong cyclonic flow likely will be maintained across the upper Great Lakes vicinity through the St. Lawrence Valley, to the south of a prominent cyclone slowly shifting eastward across northern Quebec. In lower latitudes, a prominent high is forecast to remain centered across the Four Corners vicinity, with ridging building along an axis to its east, across the southern Rockies into the central Great Plains. Within modest westerly flow on the northern periphery of this ridging, low-amplitude troughing may progress across and east-southeast of the northern Rockies into the Dakotas. However, it appears that associated forcing for ascent will generally lag to the cool side of a notable preceding surface cold front, which may advance south and west of the Black Hills and through much of the northern Great Plains and Upper Midwest by 12Z Sunday. Beneath a plume of warm elevated mixed-layer air, models indicate that large potential boundary-layer instability may develop in a pre-frontal corridor with daytime heating, probably across parts of Nebraska and Iowa through southern Wisconsin/northern Illinois into southern Lower Michigan by late Sunday afternoon. If forcing for ascent becomes sufficient to support thunderstorm development within this environment, forecast thermodynamic profiles appear conducive to a risk for severe hail and wind in stronger storms. However, it currently appears that any such activity may remain very isolated in nature, with uncertainty in location and low coverage precluding introduction of 5 percent severe probabilities. Uncertainties also remain large concerning the tropical perturbation emerging from the Caribbean, and its evolution near/west of the Florida Gulf coast Sunday through Sunday night. At this point, the risk for severe weather still appears low, but this could quickly and substantively change, and trends will need to be monitored. ..Kerr.. 08/02/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0223 AM CDT Fri Aug 02 2024 Valid 041200Z - 051200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms currently appears negligible across much of the U.S. for Sunday through Sunday night. ...Discussion... It appears that mid-level flow across the northern mid-latitudes will remain amplified through this period, with a prominent mid-level high continuing to evolve over the Canadian Yukon Territory vicinity Sunday through Sunday night. Downstream, seasonably strong cyclonic flow likely will be maintained across the upper Great Lakes vicinity through the St. Lawrence Valley, to the south of a prominent cyclone slowly shifting eastward across northern Quebec. In lower latitudes, a prominent high is forecast to remain centered across the Four Corners vicinity, with ridging building along an axis to its east, across the southern Rockies into the central Great Plains. Within modest westerly flow on the northern periphery of this ridging, low-amplitude troughing may progress across and east-southeast of the northern Rockies into the Dakotas. However, it appears that associated forcing for ascent will generally lag to the cool side of a notable preceding surface cold front, which may advance south and west of the Black Hills and through much of the northern Great Plains and Upper Midwest by 12Z Sunday. Beneath a plume of warm elevated mixed-layer air, models indicate that large potential boundary-layer instability may develop in a pre-frontal corridor with daytime heating, probably across parts of Nebraska and Iowa through southern Wisconsin/northern Illinois into southern Lower Michigan by late Sunday afternoon. If forcing for ascent becomes sufficient to support thunderstorm development within this environment, forecast thermodynamic profiles appear conducive to a risk for severe hail and wind in stronger storms. However, it currently appears that any such activity may remain very isolated in nature, with uncertainty in location and low coverage precluding introduction of 5 percent severe probabilities. Uncertainties also remain large concerning the tropical perturbation emerging from the Caribbean, and its evolution near/west of the Florida Gulf coast Sunday through Sunday night. At this point, the risk for severe weather still appears low, but this could quickly and substantively change, and trends will need to be monitored. ..Kerr.. 08/02/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1109 AM CDT Fri Aug 02 2024 Valid 021700Z - 031200Z Latest guidance suggests reduced low-level moisture into portions of central/northern Oregon and Washington this afternoon as strong heating/mixing commences, limiting the amount of instability for thunderstorm potential this afternoon/evening. Perhaps an isolated storm or two may occur, but the expected sparse coverage has led to a removal of the isolated dry thunderstorm delineation for this region. Farther south, isolated dry thunder potential has been extended across parts of central/northern California. In general, a wave of convection is expected to traverse this region from south to north throughout the day. A transition from dry to wet storms is expected with a continued southerly influx of subtropical moisture into the region, though progressive storm motions, outflow gusts, and receptive fuels should promote large-fire spread with any of this activity. ..Karstens.. 08/02/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Fri Aug 02 2024/ ...Synopsis... A midlevel disturbance will move across southern California into Oregon through the D1 period. Preceding this feature, a plume of sufficient midlevel moisture, atop a diurnally deepening boundary layer, will be in place. Increasing moisture, in combination with forcing from the midlevel disturbance, will support isolated to widely scattered high-based thunderstorms across the high terrain of California into portions of central Oregon and western Washington. ...Please see www.spc.noaa.gov/fire for graphic product... Read more