Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0747 AM CDT Tue Jul 01 2025 Valid 011300Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND SOUTH DAKOTA... ...SUMMARY... Scattered strong to severe storms are possible across parts of the Mid-Atlantic into the Northeast this afternoon/evening. A few severe thunderstorms are possible over western parts of Nebraska and South Dakota. ...Mid-Atlantic states into the Northeast and Southeast... Water-vapor imagery this morning indicates an upper trough is moving east across the Great Lakes/lower OH Valley and other minor perturbations are located over the Mid South. The primary disturbance will overspread the Appalachians by mid-late evening. In the low levels, a cold front analyzed over the southern Great Lakes into the lower OH Valley/Mid South will gradually progress east/southeast during the period. 12 UTC raob data from the OH Valley and Mid South eastward to the Mid-Atlantic region shows a very moist troposphere with limited 700-500 mb lapse rates (less than 5.5 deg C/km). Nonetheless, diurnal heating of the moist boundary layer will result in moderate buoyancy from portions of the Northeast southwestward through the Mid-Atlantic states and into the Southeast. Models continue to indicate modest southwesterly mid-level flow across the Mid-Atlantic states will contribute to adequate shear, supporting some organization of storms into line segments/clusters. Scattered thunderstorms will increase in coverage with time and numerous thunderstorms are expected by mid-late afternoon while moving east across PA/WV/VA/MD. Strong to severe gusts (50-65 mph) are possible with the stronger downdrafts. Less organized but scattered to numerous storms are forecast farther southwest into portions of the southern Appalachians with a risk for damaging gusts with the stronger storms. Strong-severe convection should spread off the Middle Atlantic Coast during the evening. ...Black Hills into the central High Plains... A weak mid-level disturbance is moving east across northern WY/southern MT towards the SD/NE vicinity later today. A weak lee trough will likely serve as a focus for thunderstorm development this afternoon from near the Black Hills southward into northeast CO. Forecast soundings show around 30-kt effective shear in the presence of steep lapse rates and moderate MLCAPE (1000-2500 J/kg). Some of the recent MPAS guidance indicates a few stronger thunderstorms will develop across western NE and perhaps into western SD. A couple of supercells with an attendant large-hail risk are possible, thereby prompting an increase in hail probabilities this outlook update. Some severe risk may linger into the mid-late evening coincident with a strengthening of a southerly LLJ centered over west-central NE before this activity dissipates. ..Smith/Broyles.. 07/01/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Jul 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... A mid-level trough will traverse the Northern Plains and Upper Midwest on Friday. This will likely be the most substantial severe weather threat during the extended period before broad, strong ridging builds across much of the eastern/central CONUS. ...Day 4/Friday... As a positively tilted mid-level trough traverses the northern Plains on Friday, strong southerly flow will advect moisture northward across a broad warm sector near the Upper Midwest. This will result in moderate to strong instability as temperatures warm well into the 80s. Widespread thunderstorms are likely along the frontal zone during the afternoon/evening. 35 to 40 knots of mid-level flow will overspread the warm sector which will provide some shear for storm organization. However, southwesterly surface winds will also increase during the afternoon within the warm front and therefore, the net shear may remain somewhat minimal. Some organized storms with a threat for large hail and severe wind gusts are possible, but the aforementioned concerns about deep-layer shear preclude the confidence needed for 15% severe weather probabilities at this time. Beyond Day 4, moderate to strong instability is forecast across much of the central and eastern CONUS with widespread thunderstorm activity likely. However, shear will remain mostly nebulous with the stronger mid-level flow confined to areas north of the better instability. Therefore, some marginal regional severe weather threat will be likely most days, but a more organized severe weather risk appears unlikely at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Jul 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... A mid-level trough will traverse the Northern Plains and Upper Midwest on Friday. This will likely be the most substantial severe weather threat during the extended period before broad, strong ridging builds across much of the eastern/central CONUS. ...Day 4/Friday... As a positively tilted mid-level trough traverses the northern Plains on Friday, strong southerly flow will advect moisture northward across a broad warm sector near the Upper Midwest. This will result in moderate to strong instability as temperatures warm well into the 80s. Widespread thunderstorms are likely along the frontal zone during the afternoon/evening. 35 to 40 knots of mid-level flow will overspread the warm sector which will provide some shear for storm organization. However, southwesterly surface winds will also increase during the afternoon within the warm front and therefore, the net shear may remain somewhat minimal. Some organized storms with a threat for large hail and severe wind gusts are possible, but the aforementioned concerns about deep-layer shear preclude the confidence needed for 15% severe weather probabilities at this time. Beyond Day 4, moderate to strong instability is forecast across much of the central and eastern CONUS with widespread thunderstorm activity likely. However, shear will remain mostly nebulous with the stronger mid-level flow confined to areas north of the better instability. Therefore, some marginal regional severe weather threat will be likely most days, but a more organized severe weather risk appears unlikely at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Jul 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... A mid-level trough will traverse the Northern Plains and Upper Midwest on Friday. This will likely be the most substantial severe weather threat during the extended period before broad, strong ridging builds across much of the eastern/central CONUS. ...Day 4/Friday... As a positively tilted mid-level trough traverses the northern Plains on Friday, strong southerly flow will advect moisture northward across a broad warm sector near the Upper Midwest. This will result in moderate to strong instability as temperatures warm well into the 80s. Widespread thunderstorms are likely along the frontal zone during the afternoon/evening. 35 to 40 knots of mid-level flow will overspread the warm sector which will provide some shear for storm organization. However, southwesterly surface winds will also increase during the afternoon within the warm front and therefore, the net shear may remain somewhat minimal. Some organized storms with a threat for large hail and severe wind gusts are possible, but the aforementioned concerns about deep-layer shear preclude the confidence needed for 15% severe weather probabilities at this time. Beyond Day 4, moderate to strong instability is forecast across much of the central and eastern CONUS with widespread thunderstorm activity likely. However, shear will remain mostly nebulous with the stronger mid-level flow confined to areas north of the better instability. Therefore, some marginal regional severe weather threat will be likely most days, but a more organized severe weather risk appears unlikely at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Jul 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... A mid-level trough will traverse the Northern Plains and Upper Midwest on Friday. This will likely be the most substantial severe weather threat during the extended period before broad, strong ridging builds across much of the eastern/central CONUS. ...Day 4/Friday... As a positively tilted mid-level trough traverses the northern Plains on Friday, strong southerly flow will advect moisture northward across a broad warm sector near the Upper Midwest. This will result in moderate to strong instability as temperatures warm well into the 80s. Widespread thunderstorms are likely along the frontal zone during the afternoon/evening. 35 to 40 knots of mid-level flow will overspread the warm sector which will provide some shear for storm organization. However, southwesterly surface winds will also increase during the afternoon within the warm front and therefore, the net shear may remain somewhat minimal. Some organized storms with a threat for large hail and severe wind gusts are possible, but the aforementioned concerns about deep-layer shear preclude the confidence needed for 15% severe weather probabilities at this time. Beyond Day 4, moderate to strong instability is forecast across much of the central and eastern CONUS with widespread thunderstorm activity likely. However, shear will remain mostly nebulous with the stronger mid-level flow confined to areas north of the better instability. Therefore, some marginal regional severe weather threat will be likely most days, but a more organized severe weather risk appears unlikely at this time. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CDT Tue Jul 01 2025 Valid 041200Z - 091200Z ...DISCUSSION... A mid-level trough will traverse the Northern Plains and Upper Midwest on Friday. This will likely be the most substantial severe weather threat during the extended period before broad, strong ridging builds across much of the eastern/central CONUS. ...Day 4/Friday... As a positively tilted mid-level trough traverses the northern Plains on Friday, strong southerly flow will advect moisture northward across a broad warm sector near the Upper Midwest. This will result in moderate to strong instability as temperatures warm well into the 80s. Widespread thunderstorms are likely along the frontal zone during the afternoon/evening. 35 to 40 knots of mid-level flow will overspread the warm sector which will provide some shear for storm organization. However, southwesterly surface winds will also increase during the afternoon within the warm front and therefore, the net shear may remain somewhat minimal. Some organized storms with a threat for large hail and severe wind gusts are possible, but the aforementioned concerns about deep-layer shear preclude the confidence needed for 15% severe weather probabilities at this time. Beyond Day 4, moderate to strong instability is forecast across much of the central and eastern CONUS with widespread thunderstorm activity likely. However, shear will remain mostly nebulous with the stronger mid-level flow confined to areas north of the better instability. Therefore, some marginal regional severe weather threat will be likely most days, but a more organized severe weather risk appears unlikely at this time. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Tue Jul 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHEAST AND THE NORTHERN PLAINS... ...SUMMARY... Scattered storms capable of large hail and severe wind gusts are forecast across the Northeast on Thursday. Isolated severe wind gusts are also possible in the northern Plains. ...Synopsis... A mid-level ridge will shift east across the central CONUS with a strong and amplifying trough across the Northeast. To the west of the ridge axis, moderate southwesterly flow is forecast from the Northwest into the northern Rockies with multiple embedded shortwave troughs. At the surface, a cold front will move quickly east across the Northeast during the afternoon/evening on Thursday. In addition, a lee cyclone will develop across the western Dakotas. A warm front will extend east from this low pressure center and a dryline/surface trough extending to its south. ...Northeast... Moderate instability is forecast to develop on Thursday afternoon ahead of a cold front across the Northeast. Cooling mid-level temperatures, associated with the deepening mid-level trough, will steepen lapse rates through the day. In addition, a moderately strong mid-level jet streak will overspread the warm sector with 40 to 50 knots of mid-level flow. A more concentrated severe weather threat may occur beneath this mid-level jet streak if moderate instability can develop where shear would be maximized. ...Northern Plains... Moderate to strong instability is forecast to develop north of the surface low across the western Dakotas. Weak isentropic ascent and height falls in an uncapped environment may support some strong storms Thursday afternoon/evening across far eastern Montana into the western Dakotas. The primary limiting factor to a greater severe weather threat will be shear with only 20 to 25 knots forecast. However, this may be sufficient for a few multicell clusters capable of isolated severe wind gusts. ..Bentley.. 07/01/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Tue Jul 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHEAST AND THE NORTHERN PLAINS... ...SUMMARY... Scattered storms capable of large hail and severe wind gusts are forecast across the Northeast on Thursday. Isolated severe wind gusts are also possible in the northern Plains. ...Synopsis... A mid-level ridge will shift east across the central CONUS with a strong and amplifying trough across the Northeast. To the west of the ridge axis, moderate southwesterly flow is forecast from the Northwest into the northern Rockies with multiple embedded shortwave troughs. At the surface, a cold front will move quickly east across the Northeast during the afternoon/evening on Thursday. In addition, a lee cyclone will develop across the western Dakotas. A warm front will extend east from this low pressure center and a dryline/surface trough extending to its south. ...Northeast... Moderate instability is forecast to develop on Thursday afternoon ahead of a cold front across the Northeast. Cooling mid-level temperatures, associated with the deepening mid-level trough, will steepen lapse rates through the day. In addition, a moderately strong mid-level jet streak will overspread the warm sector with 40 to 50 knots of mid-level flow. A more concentrated severe weather threat may occur beneath this mid-level jet streak if moderate instability can develop where shear would be maximized. ...Northern Plains... Moderate to strong instability is forecast to develop north of the surface low across the western Dakotas. Weak isentropic ascent and height falls in an uncapped environment may support some strong storms Thursday afternoon/evening across far eastern Montana into the western Dakotas. The primary limiting factor to a greater severe weather threat will be shear with only 20 to 25 knots forecast. However, this may be sufficient for a few multicell clusters capable of isolated severe wind gusts. ..Bentley.. 07/01/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Tue Jul 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHEAST AND THE NORTHERN PLAINS... ...SUMMARY... Scattered storms capable of large hail and severe wind gusts are forecast across the Northeast on Thursday. Isolated severe wind gusts are also possible in the northern Plains. ...Synopsis... A mid-level ridge will shift east across the central CONUS with a strong and amplifying trough across the Northeast. To the west of the ridge axis, moderate southwesterly flow is forecast from the Northwest into the northern Rockies with multiple embedded shortwave troughs. At the surface, a cold front will move quickly east across the Northeast during the afternoon/evening on Thursday. In addition, a lee cyclone will develop across the western Dakotas. A warm front will extend east from this low pressure center and a dryline/surface trough extending to its south. ...Northeast... Moderate instability is forecast to develop on Thursday afternoon ahead of a cold front across the Northeast. Cooling mid-level temperatures, associated with the deepening mid-level trough, will steepen lapse rates through the day. In addition, a moderately strong mid-level jet streak will overspread the warm sector with 40 to 50 knots of mid-level flow. A more concentrated severe weather threat may occur beneath this mid-level jet streak if moderate instability can develop where shear would be maximized. ...Northern Plains... Moderate to strong instability is forecast to develop north of the surface low across the western Dakotas. Weak isentropic ascent and height falls in an uncapped environment may support some strong storms Thursday afternoon/evening across far eastern Montana into the western Dakotas. The primary limiting factor to a greater severe weather threat will be shear with only 20 to 25 knots forecast. However, this may be sufficient for a few multicell clusters capable of isolated severe wind gusts. ..Bentley.. 07/01/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Tue Jul 01 2025 Valid 031200Z - 041200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHEAST AND THE NORTHERN PLAINS... ...SUMMARY... Scattered storms capable of large hail and severe wind gusts are forecast across the Northeast on Thursday. Isolated severe wind gusts are also possible in the northern Plains. ...Synopsis... A mid-level ridge will shift east across the central CONUS with a strong and amplifying trough across the Northeast. To the west of the ridge axis, moderate southwesterly flow is forecast from the Northwest into the northern Rockies with multiple embedded shortwave troughs. At the surface, a cold front will move quickly east across the Northeast during the afternoon/evening on Thursday. In addition, a lee cyclone will develop across the western Dakotas. A warm front will extend east from this low pressure center and a dryline/surface trough extending to its south. ...Northeast... Moderate instability is forecast to develop on Thursday afternoon ahead of a cold front across the Northeast. Cooling mid-level temperatures, associated with the deepening mid-level trough, will steepen lapse rates through the day. In addition, a moderately strong mid-level jet streak will overspread the warm sector with 40 to 50 knots of mid-level flow. A more concentrated severe weather threat may occur beneath this mid-level jet streak if moderate instability can develop where shear would be maximized. ...Northern Plains... Moderate to strong instability is forecast to develop north of the surface low across the western Dakotas. Weak isentropic ascent and height falls in an uncapped environment may support some strong storms Thursday afternoon/evening across far eastern Montana into the western Dakotas. The primary limiting factor to a greater severe weather threat will be shear with only 20 to 25 knots forecast. However, this may be sufficient for a few multicell clusters capable of isolated severe wind gusts. ..Bentley.. 07/01/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0120 AM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...Synopsis... A mid-level trough slowly progressing across portions of central California will continue to provide southerly transport of monsoon moisture into portions of the Great Basin on Wednesday, while a shortwave trough located further north over British Columbia will provide support for dry/windy conditions across northern Oregon into southern Washington. ...Dry/Windy... Modest mid-level westerly/southwesterly flow, coupled with deep mixing of dry boundary layer profiles, will support at least Elevated fire-weather conditions across portions of northern Oregon into southern Washington. The strongest winds will be confined to portions of the Cascade gaps/Columbia Gorge, with ERCs across the region nearing or meeting the annual 90th percentiles. ...Dry Thunderstorms... A mix of wet and dry thunderstorms will be possible from east-central Nevada into western Utah, and portions of far southeast Idaho into far western Wyoming. Fuels across significant portions of the Great Basin exceed the 98th annual percentiles, and a combination of low to modest total precipitable water vapor content and 0 - 6 km mean wind speeds ranging from 15 - 25 MPH will result in low precipitation efficiency with thunderstorm updrafts. This will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0120 AM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...Synopsis... A mid-level trough slowly progressing across portions of central California will continue to provide southerly transport of monsoon moisture into portions of the Great Basin on Wednesday, while a shortwave trough located further north over British Columbia will provide support for dry/windy conditions across northern Oregon into southern Washington. ...Dry/Windy... Modest mid-level westerly/southwesterly flow, coupled with deep mixing of dry boundary layer profiles, will support at least Elevated fire-weather conditions across portions of northern Oregon into southern Washington. The strongest winds will be confined to portions of the Cascade gaps/Columbia Gorge, with ERCs across the region nearing or meeting the annual 90th percentiles. ...Dry Thunderstorms... A mix of wet and dry thunderstorms will be possible from east-central Nevada into western Utah, and portions of far southeast Idaho into far western Wyoming. Fuels across significant portions of the Great Basin exceed the 98th annual percentiles, and a combination of low to modest total precipitable water vapor content and 0 - 6 km mean wind speeds ranging from 15 - 25 MPH will result in low precipitation efficiency with thunderstorm updrafts. This will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0120 AM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...Synopsis... A mid-level trough slowly progressing across portions of central California will continue to provide southerly transport of monsoon moisture into portions of the Great Basin on Wednesday, while a shortwave trough located further north over British Columbia will provide support for dry/windy conditions across northern Oregon into southern Washington. ...Dry/Windy... Modest mid-level westerly/southwesterly flow, coupled with deep mixing of dry boundary layer profiles, will support at least Elevated fire-weather conditions across portions of northern Oregon into southern Washington. The strongest winds will be confined to portions of the Cascade gaps/Columbia Gorge, with ERCs across the region nearing or meeting the annual 90th percentiles. ...Dry Thunderstorms... A mix of wet and dry thunderstorms will be possible from east-central Nevada into western Utah, and portions of far southeast Idaho into far western Wyoming. Fuels across significant portions of the Great Basin exceed the 98th annual percentiles, and a combination of low to modest total precipitable water vapor content and 0 - 6 km mean wind speeds ranging from 15 - 25 MPH will result in low precipitation efficiency with thunderstorm updrafts. This will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0120 AM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...Synopsis... A mid-level trough slowly progressing across portions of central California will continue to provide southerly transport of monsoon moisture into portions of the Great Basin on Wednesday, while a shortwave trough located further north over British Columbia will provide support for dry/windy conditions across northern Oregon into southern Washington. ...Dry/Windy... Modest mid-level westerly/southwesterly flow, coupled with deep mixing of dry boundary layer profiles, will support at least Elevated fire-weather conditions across portions of northern Oregon into southern Washington. The strongest winds will be confined to portions of the Cascade gaps/Columbia Gorge, with ERCs across the region nearing or meeting the annual 90th percentiles. ...Dry Thunderstorms... A mix of wet and dry thunderstorms will be possible from east-central Nevada into western Utah, and portions of far southeast Idaho into far western Wyoming. Fuels across significant portions of the Great Basin exceed the 98th annual percentiles, and a combination of low to modest total precipitable water vapor content and 0 - 6 km mean wind speeds ranging from 15 - 25 MPH will result in low precipitation efficiency with thunderstorm updrafts. This will support potential lightning ignitions, particularly with fast moving cells and on the edges of the most intense downdraft cores. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Tue Jul 01 2025 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN AND CENTRAL NEVADA... ...Synopsis... An amplified upper trough slowly progressing eastward across central California will be responsible for supporting mixed dry/wet thunderstorms across portions of northern California into southern Oregon, critical fire-weather conditions across portions of southern and central Nevada, and for pushing enough monsoonal moisture into portions of Arizona, Utah, and southeastern Idaho to support lightning over dry fuels. ...Central/Southern Nevada... Deep boundary layer mixing below strong meridional mid-level flow will result in dry and windy conditions that overlap with fuels receptive to wildfire spread (ERCs at or exceeding the 90th annual percentile). Relative humidity of 5-10% coupled with 25 MPH winds, possibly gusting to 30 MPH, are anticipated across portions of central and southern Nevada -- warranting the introduction of Critical highlights. ...Dry Thunderstorms... A mix of wet/dry thunderstorms are anticipated across portions of northern California into southern and eastern Oregon. Thunderstorms are expected to develop within deep inverted-v boundary-layer profiles with total precipitable water content between 0.5 - 0.75 in, and 0 - 6 km mean wind speeds of 15-20 MPH. With ERC percentiles climbing to the 70th-80th annual percentiles, lightning over dry fuels with little wetting precipitation will pose a fire-weather risk. Further east across portions of northern Arizona, western/central Utah, and far southeastern Idaho, a mix of wet and dry thunderstorms is expected. ERC fuel percentiles are more significant across this region, ranging from the 90th annual percentiles to exceeding the 98th annual percentiles across large portions of the region. With total precipitable water vapor content forecast between 0.5 and 0.8 inches resulting in lower precipitation efficiency, dry lightning ignitions will be possible. ..Halbert.. 07/01/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more