Severe Storms

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0739 PM CDT Sat Oct 21 2023 Valid 220100Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms will not occur through tonight across the contiguous United States. ...Synopsis... Water-vapor imagery early this evening shows a mid-level shortwave trough moving east across southern ID/northern UT and downstream of a larger trough over the eastern Pacific. A few thunderstorms have been observed this evening in association with weak buoyancy/appreciable ascent with the ID/UT disturbance. This activity may linger for a couple of more hours before the zone of stronger ascent moves east into a more dry environment farther east in WY. Elsewhere, tranquil conditions reside over much of the Lower 48 states owing to building surface high pressure over the north-central U.S. and a departing mid-level shortwave trough over New England. ..Smith.. 10/22/2023 Read more

No watches are valid as of Fri Oct 20 02:00:02 UTC 2023.

No Mesoscale Discussions are in effect as of Fri Oct 20 02:00:02 UTC 2023.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 PM CDT Thu Oct 19 2023 Valid 200100Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S. through tonight. ...01Z Update... Scattered thunderstorm development has been increasing in a general corridor near/southwest of Louisville KY into areas around the Nashville TN vicinity. This is in the wake of an initial mid-level perturbation shifting from the lower Ohio Valley into the lower Great Lakes, and ahead of another strengthening impulse forecast to continue digging southeast of the Upper Midwest through the lower Ohio and Tennessee Valleys by late tonight. Aided by a narrow corridor of modest low-level moistening, within a zone of enhanced low-level warm advection, it appears that ongoing activity may slowly spread eastward across portions of central Kentucky and middle Tennessee through 03-05Z before diminishing. Overnight, additional thunderstorm development is possible as forcing for ascent refocuses southeastward into the southern Appalachians vicinity. Despite the presence of at least modest shear, it still appears that thermodynamic profiles characterized by only modest steepening of lapse rates, coupled with the limited moisture return, will minimize the risk for severe hail and/or wind. ..Kerr.. 10/20/2023 Read more

No watches are valid as of Thu Oct 19 02:19:01 UTC 2023.

No Mesoscale Discussions are in effect as of Thu Oct 19 02:19:01 UTC 2023.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 PM CDT Wed Oct 18 2023 Valid 190100Z - 191200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms appears negligible across the U.S. through tonight. ...01Z Update... Convection, beneath the mid-level cold core of the low digging to the east-southeast of the mid Missouri Valley, briefly produced some lightning during the late afternoon near the western Minnesota/Iowa border vicinity. However, this appeared largely supported by destabilization associated with insolation, and has diminished with the loss of daytime heating. More recently, some lightning has been noted within the convective band ahead of the trailing short wave trough, along an associated weak southeastward advancing cold front, to the west-northwest of Springfield MO. While this convective band could generate additional lightning as it spreads eastward across the middle Mississippi/lower Ohio Valleys overnight, it appears that this will be rather sporadic and sparse, with destabilization forecast to remain limited by only modest steepening of mid/upper lapse rates and weak boundary-layer moisture return. ..Kerr.. 10/19/2023 Read more

No watches are valid as of Wed Oct 18 02:59:01 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Oct 18 02:59:01 UTC 2023.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 PM CDT Tue Oct 17 2023 Valid 180100Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Discussion... The onset of nocturnal cooling this evening has led to progressive stabilization of the airmass, across both the northern Plains vicinity, and across Arizona/New Mexico -- areas where ongoing or recent thunderstorm activity is observed. Lightning has diminished substantially across the northern Plains area, with no new flashes indicated and CAPE rapidly diminishing. As such, the 10% thunder area is being removed across this region. Across southeastern Arizona/southwestern New Mexico, stabilization is ongoing, though weak instability still remains locally. While lightning activity is rapidly diminishing -- and this trend to continue -- will maintain a small thunder area to cover lightning potential over the next 1 to 2 hours. ..Goss.. 10/18/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0757 PM CDT Tue Oct 17 2023 Valid 180100Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. ...Discussion... The onset of nocturnal cooling this evening has led to progressive stabilization of the airmass, across both the northern Plains vicinity, and across Arizona/New Mexico -- areas where ongoing or recent thunderstorm activity is observed. Lightning has diminished substantially across the northern Plains area, with no new flashes indicated and CAPE rapidly diminishing. As such, the 10% thunder area is being removed across this region. Across southeastern Arizona/southwestern New Mexico, stabilization is ongoing, though weak instability still remains locally. While lightning activity is rapidly diminishing -- and this trend to continue -- will maintain a small thunder area to cover lightning potential over the next 1 to 2 hours. ..Goss.. 10/18/2023 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0454 PM CDT Tue Oct 17 2023 Valid 191200Z - 251200Z A strong mid-level trough will move from the Plains to the Great Lakes Thursday and Friday and amplify into a large trough across the eastern CONUS this weekend. A strong surface low is looking increasingly likely near the Northeast this weekend. This will likely result in dry and breezy conditions across much of the eastern CONUS later this week and this weekend, but the combination of cool temperatures, moist fuels, and precipitation associated with this system should mitigate the fire weather threat. The next week is expected to be dry across the Southwest and southern Plains. Therefore, fuels are expected to dry, and with cooler temperatures starting to arrive, finer fuels may start to become dormant in some areas. Therefore, there may be at least somewhat receptive fuels when the next mid-level trough crosses the Southwest early next week. This trough is expected to bring low-elevation rain and mountain snow, but there may be a period in the 12 to 24 hours ahead of trough arrival where there may be some increased fire weather threat. ..Bentley.. 10/17/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Oct 17 00:57:02 UTC 2023.

No Mesoscale Discussions are in effect as of Tue Oct 17 00:57:02 UTC 2023.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0740 PM CDT Mon Oct 16 2023 Valid 170100Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes remain possible over parts of northern Washington and vicinity the next several hours. Severe storms are not expected. ...01z Update... A few lightning flashes remain possible across northern WA into far northern ID with ongoing showers/convection. Thunderstorm chances should gradually wane through the nighttime hours. Severe storms are not expected. ..Leitman.. 10/17/2023 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0447 PM CDT Mon Oct 16 2023 Valid 181200Z - 241200Z A strong mid-level trough will move from the Plains to the Great Lakes later this week and amplify into a large trough across the eastern CONUS this weekend. There is still considerable uncertainty regarding trough location and phasing, but a strong surface low may be possible near the Northeast this weekend. This should result in some dry and breezy conditions across much of the eastern CONUS later this week and this weekend, but temperatures should be cool, much of this area will see precipitation later this week, and fuels are moist. Therefore, fire weather concerns will be minimal. Much of the extended period will be dry across the Southwest and southern Plains. Therefore, fuels are expected to dry, and with cooler temperature starting to arrive, finer fuels may start to become dormant in some areas. Therefore, there may be at least somewhat receptive fuels when the next mid-level trough crosses the Southwest early next week. This trough is expected to bring low-elevation rain and mountain snow, but there may be a period in the 12 to 24 hours ahead of trough arrival where there may be some increased fire weather threat. ..Bentley.. 10/16/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Oct 16 00:57:01 UTC 2023.

No Mesoscale Discussions are in effect as of Mon Oct 16 00:57:01 UTC 2023.

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 PM CDT Sun Oct 15 2023 Valid 160100Z - 161200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected through tonight. ...Discussion... With a surface cold front now clearing the far southeastern tip of Florida (southeastern Dade County) and the Keys, and thunder potential overnight will remain offshore. Elsewhere, with dry/stable air spilling across the eastern two-thirds of the U.S. and a ridge prevailing over the West, no thunderstorms are expected through the rest of the period. ..Goss.. 10/16/2023 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0456 PM CDT Sun Oct 15 2023 Valid 171200Z - 231200Z A mid-level shortwave trough will traverse the top of a mid-level ridge across the northern Rockies on Tuesday and amplify as it moves southeast into the eastern CONUS for the end of the week. As this occurs, an area of surface low-pressure will develop across the Plains and eventually move into the eastern CONUS. Breezy conditions will accompany this surface low, but relatively cool temperatures should keep relative humidity somewhat higher. Fuels remain moist across much of the CONUS, particularly where the dry and breezy conditions will be present. Therefore, fire weather concerns should remain minimal for the extended period. ..Bentley.. 10/15/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more