Severe Storms

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0145 AM CDT Wed Jul 16 2025 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential appear low/uncertain on Friday. ...Synopsis... Broad, cyclonic upper flow will persist across the northern tier of the U.S. on Friday. Meanwhile, the subtropical ridge will intensify over the Southeast and southern Plains. A weak shortwave impulse and/or MCV is forecast to move from the OH Valley toward the Chesapeake Bay vicinity near a stalled surface front. This may provide focus for some severe potential Friday afternoon/early evening. However, confidence in this scenario is low as prior day's convection will heavily influence convective evolution on Friday. Further west, a surface trough/weak lee low development across the central High Plains will allow for northward transport of richer boundary layer moisture from the southern in the central and northern Plains. Forcing mechanisms are unclear, and capping may suppress convection. If storms can develop in the warm advection regime, some severe potential would be possible given the very moist and unstable environment. Large model disparity also is noted in the location and evolution of the Plains surface low. Overall the risk appears too uncertain/conditional at this time to include probabilities. ..Leitman.. 07/16/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0145 AM CDT Wed Jul 16 2025 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential appear low/uncertain on Friday. ...Synopsis... Broad, cyclonic upper flow will persist across the northern tier of the U.S. on Friday. Meanwhile, the subtropical ridge will intensify over the Southeast and southern Plains. A weak shortwave impulse and/or MCV is forecast to move from the OH Valley toward the Chesapeake Bay vicinity near a stalled surface front. This may provide focus for some severe potential Friday afternoon/early evening. However, confidence in this scenario is low as prior day's convection will heavily influence convective evolution on Friday. Further west, a surface trough/weak lee low development across the central High Plains will allow for northward transport of richer boundary layer moisture from the southern in the central and northern Plains. Forcing mechanisms are unclear, and capping may suppress convection. If storms can develop in the warm advection regime, some severe potential would be possible given the very moist and unstable environment. Large model disparity also is noted in the location and evolution of the Plains surface low. Overall the risk appears too uncertain/conditional at this time to include probabilities. ..Leitman.. 07/16/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0142 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...Synopsis... Moisture will increase on D2/Thursday across the Southwest with a cut off low off the coast of Baja California. This moisture aided by upper-level forcing will bring an increase in thunderstorm activity across much of Arizona into southern Utah with increasing chances for wetting rainfall. On the fringes of the deeper moisture plume, isolated dry thunderstorms will be possible across portions of western Colorado into Utah, eastern Nevada, southern Idaho, and southwestern Wyoming. As such, a broad area of isolated dry thunderstorms was maintained with this outlook. ..Thornton.. 07/16/2025 ...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 0142 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...Synopsis... Moisture will increase on D2/Thursday across the Southwest with a cut off low off the coast of Baja California. This moisture aided by upper-level forcing will bring an increase in thunderstorm activity across much of Arizona into southern Utah with increasing chances for wetting rainfall. On the fringes of the deeper moisture plume, isolated dry thunderstorms will be possible across portions of western Colorado into Utah, eastern Nevada, southern Idaho, and southwestern Wyoming. As such, a broad area of isolated dry thunderstorms was maintained with this outlook. ..Thornton.. 07/16/2025 ...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 0142 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...Synopsis... Moisture will increase on D2/Thursday across the Southwest with a cut off low off the coast of Baja California. This moisture aided by upper-level forcing will bring an increase in thunderstorm activity across much of Arizona into southern Utah with increasing chances for wetting rainfall. On the fringes of the deeper moisture plume, isolated dry thunderstorms will be possible across portions of western Colorado into Utah, eastern Nevada, southern Idaho, and southwestern Wyoming. As such, a broad area of isolated dry thunderstorms was maintained with this outlook. ..Thornton.. 07/16/2025 ...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 0142 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...Synopsis... Moisture will increase on D2/Thursday across the Southwest with a cut off low off the coast of Baja California. This moisture aided by upper-level forcing will bring an increase in thunderstorm activity across much of Arizona into southern Utah with increasing chances for wetting rainfall. On the fringes of the deeper moisture plume, isolated dry thunderstorms will be possible across portions of western Colorado into Utah, eastern Nevada, southern Idaho, and southwestern Wyoming. As such, a broad area of isolated dry thunderstorms was maintained with this outlook. ..Thornton.. 07/16/2025 ...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 0142 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...Synopsis... Moisture will increase on D2/Thursday across the Southwest with a cut off low off the coast of Baja California. This moisture aided by upper-level forcing will bring an increase in thunderstorm activity across much of Arizona into southern Utah with increasing chances for wetting rainfall. On the fringes of the deeper moisture plume, isolated dry thunderstorms will be possible across portions of western Colorado into Utah, eastern Nevada, southern Idaho, and southwestern Wyoming. As such, a broad area of isolated dry thunderstorms was maintained with this outlook. ..Thornton.. 07/16/2025 ...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 0141 AM CDT Wed Jul 16 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ..Thornton.. 07/16/2025 ...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 0141 AM CDT Wed Jul 16 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ..Thornton.. 07/16/2025 ...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 0141 AM CDT Wed Jul 16 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ..Thornton.. 07/16/2025 ...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 0141 AM CDT Wed Jul 16 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ..Thornton.. 07/16/2025 ...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 0141 AM CDT Wed Jul 16 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN COLORADO INTO EASTERN UTAH... ...Synopsis... A departing mid-level trough will bring continued breezy conditions across portions of southern Nevada into west-central Utah. This will overlap with relative humidity reductions around 10-15 mph bringing Elevated fire weather conditions. In addition to the background flow, nearby high based convection will likely bring gusty and erratic winds. ...Dry Thunderstorms... A broad area of dry thunderstorms is expected across northern AZ into western CO, UT, southern WY, and portions of eastern NV. Across western Colorado into eastern Utah, forcing for ascent with the upper-level trough will aid in more scattered coverage of thunderstorm activity. Sounding profiles within this region show elevated instability amid very dry low-levels which will promote high based convection with efficient lightning production and little to no measurable precipitation. Fuels within this region remain critically dry with several ongoing fires. ..Thornton.. 07/16/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0516 Status Updates
STATUS REPORT ON WW 516 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 NE HSI TO 15 W LNK TO 25 ENE LNK TO 5 WNW OMA TO 15 WSW DNS TO 20 N DNS. ..BENTLEY..07/16/25 ATTN...WFO...FSD...OAX...GID... STATUS REPORT FOR WS 516 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC071-129-155-160740- IA . IOWA COUNTIES INCLUDED ARE FREMONT MILLS POTTAWATTAMIE KSC089-183-160740- KS . KANSAS COUNTIES INCLUDED ARE JEWELL SMITH NEC025-035-059-067-081-095-097-109-127-129-131-133-151-153-159- 169-181-185-160740- NE . NEBRASKA COUNTIES INCLUDED ARE CASS CLAY FILLMORE GAGE HAMILTON JEFFERSON JOHNSON LANCASTER NEMAHA Read more

WW 0516 Status Updates
STATUS REPORT ON WW 516 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 NE HSI TO 15 W LNK TO 25 ENE LNK TO 5 WNW OMA TO 15 WSW DNS TO 20 N DNS. ..BENTLEY..07/16/25 ATTN...WFO...FSD...OAX...GID... STATUS REPORT FOR WS 516 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC071-129-155-160740- IA . IOWA COUNTIES INCLUDED ARE FREMONT MILLS POTTAWATTAMIE KSC089-183-160740- KS . KANSAS COUNTIES INCLUDED ARE JEWELL SMITH NEC025-035-059-067-081-095-097-109-127-129-131-133-151-153-159- 169-181-185-160740- NE . NEBRASKA COUNTIES INCLUDED ARE CASS CLAY FILLMORE GAGE HAMILTON JEFFERSON JOHNSON LANCASTER NEMAHA Read more

WW 516 SEVERE TSTM IA KS MN NE 160140Z - 160800Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 516 NWS Storm Prediction Center Norman OK 840 PM CDT Tue Jul 15 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western Iowa Extreme north central Kansas Extreme southwest Minnesota Eastern Nebraska * Effective this Tuesday night and Wednesday morning from 840 PM until 300 AM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...A line of storms will continue spread east-southeastward through the overnight hours with the potential to produce occasional severe outflow gusts of 60-70 mph and isolated large hail near 1 inch diameter. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 15 miles west northwest of Worthington MN to 40 miles west southwest of Beatrice NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 513...WW 514...WW 515... AVIATION...A few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 30030. ...Thompson Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND NORTHEAST... ...SUMMARY... Isolated damaging gusts are possible from southern Missouri into the Ohio Valley, Mid-Atlantic, and Northeast on Thursday. ...Northeast... A shortwave trough is forecast to extend from southern Quebec to near Long Island early Thursday. At the surface, low pressure will track from Lake Huron northeast along the St. Lawrence Valley. A trailing cold front will develop east across the Upper Ohio Valley and Northeast during the afternoon and evening. Ahead of the front, a very moist airmass will be in place, supporting MLCAPE values from around 1000-2000 J/kg. While 30-40 kt of westerly flow will overspread portions of the Northeast, effective shear will remain modest, but sufficient for isolated organized cells (20-30 kt). The surface low is likely to remain north of the international border, but the cold front should provide some focus for afternoon/evening thunderstorm activity. However, subsidence behind the morning shortwave and possibly some early day showers and cloud cover could hinder thunderstorm development initially. As a result storms may develop a bit further south and east than previously forecast, and the Marginal risk (level 1 of 5) has been removed for parts of the Upper OH Valley/Lower Great Lakes vicinity. Storms that do develop across the Northeast still may pose a risk for locally strong gusts, and closer to the surface low, a tornado or two. ...Southern MO/OH Valley to the Mid-Atlantic... A seasonally very moist airmass will reside to the south of the southward sagging cold front extending from the MO Ozarks into southern IL/IN/OH. A corridor of strong instability is expected ahead of the front, aided by 70s dewpoints and heating into the mid 80s to mid 90s. Vertical shear will be much weaker with southward extent, but any MCVs from prior day's convection coupled with the sagging cold front, should provide focused for scattered thunderstorm development. Thunderstorm clusters will mainly pose a risk for strong gusts from water laden downdrafts. Additional storms are expected to develop over the higher terrain of WV/VA along a surface trough and ahead of the surface cold front. A similar environment to that further east will exist (high CAPE, weak shear). Thunderstorm clusters may produce isolated strong gusts. ..Leitman.. 07/16/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND NORTHEAST... ...SUMMARY... Isolated damaging gusts are possible from southern Missouri into the Ohio Valley, Mid-Atlantic, and Northeast on Thursday. ...Northeast... A shortwave trough is forecast to extend from southern Quebec to near Long Island early Thursday. At the surface, low pressure will track from Lake Huron northeast along the St. Lawrence Valley. A trailing cold front will develop east across the Upper Ohio Valley and Northeast during the afternoon and evening. Ahead of the front, a very moist airmass will be in place, supporting MLCAPE values from around 1000-2000 J/kg. While 30-40 kt of westerly flow will overspread portions of the Northeast, effective shear will remain modest, but sufficient for isolated organized cells (20-30 kt). The surface low is likely to remain north of the international border, but the cold front should provide some focus for afternoon/evening thunderstorm activity. However, subsidence behind the morning shortwave and possibly some early day showers and cloud cover could hinder thunderstorm development initially. As a result storms may develop a bit further south and east than previously forecast, and the Marginal risk (level 1 of 5) has been removed for parts of the Upper OH Valley/Lower Great Lakes vicinity. Storms that do develop across the Northeast still may pose a risk for locally strong gusts, and closer to the surface low, a tornado or two. ...Southern MO/OH Valley to the Mid-Atlantic... A seasonally very moist airmass will reside to the south of the southward sagging cold front extending from the MO Ozarks into southern IL/IN/OH. A corridor of strong instability is expected ahead of the front, aided by 70s dewpoints and heating into the mid 80s to mid 90s. Vertical shear will be much weaker with southward extent, but any MCVs from prior day's convection coupled with the sagging cold front, should provide focused for scattered thunderstorm development. Thunderstorm clusters will mainly pose a risk for strong gusts from water laden downdrafts. Additional storms are expected to develop over the higher terrain of WV/VA along a surface trough and ahead of the surface cold front. A similar environment to that further east will exist (high CAPE, weak shear). Thunderstorm clusters may produce isolated strong gusts. ..Leitman.. 07/16/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND NORTHEAST... ...SUMMARY... Isolated damaging gusts are possible from southern Missouri into the Ohio Valley, Mid-Atlantic, and Northeast on Thursday. ...Northeast... A shortwave trough is forecast to extend from southern Quebec to near Long Island early Thursday. At the surface, low pressure will track from Lake Huron northeast along the St. Lawrence Valley. A trailing cold front will develop east across the Upper Ohio Valley and Northeast during the afternoon and evening. Ahead of the front, a very moist airmass will be in place, supporting MLCAPE values from around 1000-2000 J/kg. While 30-40 kt of westerly flow will overspread portions of the Northeast, effective shear will remain modest, but sufficient for isolated organized cells (20-30 kt). The surface low is likely to remain north of the international border, but the cold front should provide some focus for afternoon/evening thunderstorm activity. However, subsidence behind the morning shortwave and possibly some early day showers and cloud cover could hinder thunderstorm development initially. As a result storms may develop a bit further south and east than previously forecast, and the Marginal risk (level 1 of 5) has been removed for parts of the Upper OH Valley/Lower Great Lakes vicinity. Storms that do develop across the Northeast still may pose a risk for locally strong gusts, and closer to the surface low, a tornado or two. ...Southern MO/OH Valley to the Mid-Atlantic... A seasonally very moist airmass will reside to the south of the southward sagging cold front extending from the MO Ozarks into southern IL/IN/OH. A corridor of strong instability is expected ahead of the front, aided by 70s dewpoints and heating into the mid 80s to mid 90s. Vertical shear will be much weaker with southward extent, but any MCVs from prior day's convection coupled with the sagging cold front, should provide focused for scattered thunderstorm development. Thunderstorm clusters will mainly pose a risk for strong gusts from water laden downdrafts. Additional storms are expected to develop over the higher terrain of WV/VA along a surface trough and ahead of the surface cold front. A similar environment to that further east will exist (high CAPE, weak shear). Thunderstorm clusters may produce isolated strong gusts. ..Leitman.. 07/16/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND NORTHEAST... ...SUMMARY... Isolated damaging gusts are possible from southern Missouri into the Ohio Valley, Mid-Atlantic, and Northeast on Thursday. ...Northeast... A shortwave trough is forecast to extend from southern Quebec to near Long Island early Thursday. At the surface, low pressure will track from Lake Huron northeast along the St. Lawrence Valley. A trailing cold front will develop east across the Upper Ohio Valley and Northeast during the afternoon and evening. Ahead of the front, a very moist airmass will be in place, supporting MLCAPE values from around 1000-2000 J/kg. While 30-40 kt of westerly flow will overspread portions of the Northeast, effective shear will remain modest, but sufficient for isolated organized cells (20-30 kt). The surface low is likely to remain north of the international border, but the cold front should provide some focus for afternoon/evening thunderstorm activity. However, subsidence behind the morning shortwave and possibly some early day showers and cloud cover could hinder thunderstorm development initially. As a result storms may develop a bit further south and east than previously forecast, and the Marginal risk (level 1 of 5) has been removed for parts of the Upper OH Valley/Lower Great Lakes vicinity. Storms that do develop across the Northeast still may pose a risk for locally strong gusts, and closer to the surface low, a tornado or two. ...Southern MO/OH Valley to the Mid-Atlantic... A seasonally very moist airmass will reside to the south of the southward sagging cold front extending from the MO Ozarks into southern IL/IN/OH. A corridor of strong instability is expected ahead of the front, aided by 70s dewpoints and heating into the mid 80s to mid 90s. Vertical shear will be much weaker with southward extent, but any MCVs from prior day's convection coupled with the sagging cold front, should provide focused for scattered thunderstorm development. Thunderstorm clusters will mainly pose a risk for strong gusts from water laden downdrafts. Additional storms are expected to develop over the higher terrain of WV/VA along a surface trough and ahead of the surface cold front. A similar environment to that further east will exist (high CAPE, weak shear). Thunderstorm clusters may produce isolated strong gusts. ..Leitman.. 07/16/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1238 AM CDT Wed Jul 16 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN MISSOURI INTO PARTS OF THE OHIO VALLEY...MID-ATLANTIC...AND NORTHEAST... ...SUMMARY... Isolated damaging gusts are possible from southern Missouri into the Ohio Valley, Mid-Atlantic, and Northeast on Thursday. ...Northeast... A shortwave trough is forecast to extend from southern Quebec to near Long Island early Thursday. At the surface, low pressure will track from Lake Huron northeast along the St. Lawrence Valley. A trailing cold front will develop east across the Upper Ohio Valley and Northeast during the afternoon and evening. Ahead of the front, a very moist airmass will be in place, supporting MLCAPE values from around 1000-2000 J/kg. While 30-40 kt of westerly flow will overspread portions of the Northeast, effective shear will remain modest, but sufficient for isolated organized cells (20-30 kt). The surface low is likely to remain north of the international border, but the cold front should provide some focus for afternoon/evening thunderstorm activity. However, subsidence behind the morning shortwave and possibly some early day showers and cloud cover could hinder thunderstorm development initially. As a result storms may develop a bit further south and east than previously forecast, and the Marginal risk (level 1 of 5) has been removed for parts of the Upper OH Valley/Lower Great Lakes vicinity. Storms that do develop across the Northeast still may pose a risk for locally strong gusts, and closer to the surface low, a tornado or two. ...Southern MO/OH Valley to the Mid-Atlantic... A seasonally very moist airmass will reside to the south of the southward sagging cold front extending from the MO Ozarks into southern IL/IN/OH. A corridor of strong instability is expected ahead of the front, aided by 70s dewpoints and heating into the mid 80s to mid 90s. Vertical shear will be much weaker with southward extent, but any MCVs from prior day's convection coupled with the sagging cold front, should provide focused for scattered thunderstorm development. Thunderstorm clusters will mainly pose a risk for strong gusts from water laden downdrafts. Additional storms are expected to develop over the higher terrain of WV/VA along a surface trough and ahead of the surface cold front. A similar environment to that further east will exist (high CAPE, weak shear). Thunderstorm clusters may produce isolated strong gusts. ..Leitman.. 07/16/2025 Read more