Severe Storms

MD 1546 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR NEW ENGLAND
Mesoscale Discussion 1546 NWS Storm Prediction Center Norman OK 0907 AM CDT Thu Jul 03 2025 Areas affected...New England Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 031407Z - 031600Z Probability of Watch Issuance...80 percent SUMMARY...Multiple rounds of strong to isolated severe thunderstorms appear increasingly likely across parts of New England into this afternoon. One or two Severe Thunderstorm Watches will probably be issued before midday as storms intensify eastward. DISCUSSION...Two areas of ongoing convection, one along the ME/QC border and the other near the NY/VT border vicinity, should intensify as they spread east across parts of New England into midday. 12Z CAR sounding sampled a moderate combination of MLCAPE and effective bulk shear with convective temperature in the upper 70s. 14Z surface temperatures have warmed into the upper 70s to low 80s with abundant insolation ahead of both convective areas. While the 12Z HRRR appears to be poorly handling the near-term scenario, it does suggest another round of strong to potentially severe convection may emanate eastward from ongoing storms across the Saint Lawrence Valley near northern NY. A mix of isolated severe hail with a predominant threat of scattered strong to localized severe gusts producing damaging winds seems probable. ..Grams/Mosier.. 07/03/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CAR...GYX...BOX...BTV...ALY... LAT...LON 46086650 44986752 43766937 42547080 42357142 42407258 42577335 43197332 43997237 44717200 45007240 45337216 46427037 46976937 47356811 47126737 46086650 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

WW 0483 Status Updates
STATUS REPORT ON WW 483 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..GRAMS..07/03/25 ATTN...WFO...GYX...CAR... STATUS REPORT FOR WS 483 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MEC001-003-005-007-009-011-013-015-017-019-021-023-025-027-029- 031-031640- ME . MAINE COUNTIES INCLUDED ARE ANDROSCOGGIN AROOSTOOK CUMBERLAND FRANKLIN HANCOCK KENNEBEC KNOX LINCOLN OXFORD PENOBSCOT PISCATAQUIS SAGADAHOC SOMERSET WALDO WASHINGTON YORK NHC001-003-005-007-009-011-013-015-017-019-031640- NH . NEW HAMPSHIRE COUNTIES INCLUDED ARE BELKNAP CARROLL CHESHIRE COOS GRAFTON HILLSBOROUGH MERRIMACK ROCKINGHAM STRAFFORD SULLIVAN THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE Read more

WW 0483 Status Updates
STATUS FOR WATCH 0483 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Thu Jul 3 14:10:02 UTC 2025.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0713 AM CDT Thu Jul 03 2025 Valid 031300Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTH DAKOTA AND MUCH OF THE NORTHEAST... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging winds and large hail are forecast across parts of the Northeast and northern Plains today. ...Northern Plains... Water-vapor imagery this morning indicates a weak disturbance over western ND is cresting a central U.S. upper ridge. An upstream minor perturbation is forecast to move from northern WY/MT eastward into western ND by late afternoon/evening. Coincident with this feature, an elongated weak low is forecast from the north-central High Plains northward into SK, with an attendant warm frontal zone draped east-southeast from ND into the Upper Midwest. A seasonably moist boundary layer is indicated by morning surface observations. Dewpoints currently range from the lower 60s deg F over ND to upper 60s to near 70 in central and eastern SD. Steep 700-500 mb lapse rates coupled with heating in wake of morning cloud debris/shower activity, will likely result in a weakly capped and very unstable airmass by mid-late afternoon over ND where low-level moisture is maximized. Isolated to scattered storms are forecast to develop 20-23 UTC with a few supercells possible. A risk for very large hail and perhaps a tornado would accompany the supercells before storm outflow and mergers leading to upscale growth into one or two eastward-moving clusters during the evening. Have introduced a significant wind highlight for potential peak gusts in the 70-85 mph range. A focused mesoscale wind corridor is indicated by some 00z HREF and MPAS members but sufficient model variability precludes higher probabilities at this time. This activity will likely weaken late this evening as it approaches the Red River and adjacent portions of northern MN. ...Northeast... An upper trough with an embedded 40-50 kt mid-level speed maximum will pivot across the Northeast today. A related surface cold front will likewise develop eastward across this region through the afternoon/evening. Heating will act to destabilize a moist airmass and support weak to moderate buoyancy (500-1500 J/kg MLCAPE) along/ahead of the cold front by early afternoon. Sufficient deep-layer shear will favor multicellular and some transient supercell organization. Scattered damaging (50-65 mph) winds should be the primary severe threat as low-level lapse rates gradually steepen. But, some large hail may occur given favorable shear, especially with any supercell. The severe risk will likely diminish by the early to mid evening as thunderstorms push east of the coast. ...Upper Midwest... Weak forcing aloft and the persistence of the upper ridge should tend to limit convective development in an otherwise moderately to strongly unstable airmass. Still, any thunderstorms which can develop, perhaps aided by modest low-level warm advection this evening/tonight, could pose an isolated severe hail/wind threat. ..Smith/Broyles.. 07/03/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Thu Jul 03 2025 Valid 061200Z - 111200Z ...DISCUSSION... During the extended forecast period, a mid-level ridge will build across the InterMountain West. Aside from the primary ridge, there will be several mid-level shortwave troughs throughout the flow across the Northwest and also from the Great Lakes to the Atlantic coast. Widespread thunderstorm activity is expected throughout the period, but stronger mid-level flow/shear should mostly stay north of the stronger instability early in the period. At some point next week (mid week according to the GFS and late next week into the weekend ECMWF) mid-level northwesterly flow will likely strengthen across the Plains (to the east of the primary ridge). Whenever this occurs, the pattern would favor severe MCSs given the forecast strong instability and moderate deep-layer shear. However, the uncertainty in the upper-level pattern remains too great to provide an accurate forecast of the timing and location of the greatest severe weather threat toward the middle to late part of next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Thu Jul 03 2025 Valid 061200Z - 111200Z ...DISCUSSION... During the extended forecast period, a mid-level ridge will build across the InterMountain West. Aside from the primary ridge, there will be several mid-level shortwave troughs throughout the flow across the Northwest and also from the Great Lakes to the Atlantic coast. Widespread thunderstorm activity is expected throughout the period, but stronger mid-level flow/shear should mostly stay north of the stronger instability early in the period. At some point next week (mid week according to the GFS and late next week into the weekend ECMWF) mid-level northwesterly flow will likely strengthen across the Plains (to the east of the primary ridge). Whenever this occurs, the pattern would favor severe MCSs given the forecast strong instability and moderate deep-layer shear. However, the uncertainty in the upper-level pattern remains too great to provide an accurate forecast of the timing and location of the greatest severe weather threat toward the middle to late part of next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Thu Jul 03 2025 Valid 061200Z - 111200Z ...DISCUSSION... During the extended forecast period, a mid-level ridge will build across the InterMountain West. Aside from the primary ridge, there will be several mid-level shortwave troughs throughout the flow across the Northwest and also from the Great Lakes to the Atlantic coast. Widespread thunderstorm activity is expected throughout the period, but stronger mid-level flow/shear should mostly stay north of the stronger instability early in the period. At some point next week (mid week according to the GFS and late next week into the weekend ECMWF) mid-level northwesterly flow will likely strengthen across the Plains (to the east of the primary ridge). Whenever this occurs, the pattern would favor severe MCSs given the forecast strong instability and moderate deep-layer shear. However, the uncertainty in the upper-level pattern remains too great to provide an accurate forecast of the timing and location of the greatest severe weather threat toward the middle to late part of next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Thu Jul 03 2025 Valid 061200Z - 111200Z ...DISCUSSION... During the extended forecast period, a mid-level ridge will build across the InterMountain West. Aside from the primary ridge, there will be several mid-level shortwave troughs throughout the flow across the Northwest and also from the Great Lakes to the Atlantic coast. Widespread thunderstorm activity is expected throughout the period, but stronger mid-level flow/shear should mostly stay north of the stronger instability early in the period. At some point next week (mid week according to the GFS and late next week into the weekend ECMWF) mid-level northwesterly flow will likely strengthen across the Plains (to the east of the primary ridge). Whenever this occurs, the pattern would favor severe MCSs given the forecast strong instability and moderate deep-layer shear. However, the uncertainty in the upper-level pattern remains too great to provide an accurate forecast of the timing and location of the greatest severe weather threat toward the middle to late part of next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Thu Jul 03 2025 Valid 061200Z - 111200Z ...DISCUSSION... During the extended forecast period, a mid-level ridge will build across the InterMountain West. Aside from the primary ridge, there will be several mid-level shortwave troughs throughout the flow across the Northwest and also from the Great Lakes to the Atlantic coast. Widespread thunderstorm activity is expected throughout the period, but stronger mid-level flow/shear should mostly stay north of the stronger instability early in the period. At some point next week (mid week according to the GFS and late next week into the weekend ECMWF) mid-level northwesterly flow will likely strengthen across the Plains (to the east of the primary ridge). Whenever this occurs, the pattern would favor severe MCSs given the forecast strong instability and moderate deep-layer shear. However, the uncertainty in the upper-level pattern remains too great to provide an accurate forecast of the timing and location of the greatest severe weather threat toward the middle to late part of next week. Read more