Severe Storms

No Mesoscale Discussions are in effect as of Mon Mar 20 21:22:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Mon Mar 20 2023 Valid 202000Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. No changes were required to the previous outlook. ..Jewell.. 03/20/2023 .PREV DISCUSSION... /ISSUED 1103 AM CDT Mon Mar 20 2023/ ...Synopsis... A midlevel shortwave impulse will continue to shift east across the Great Basin toward the central Rockies today/tonight. Midlevel moisture, and cool temperatures aloft, combined with steep lapse rates will support 100-300 J/kg MUCAPE. Isolated lightning flashes will continue through the forecast period, especially across southeast ID, UT and western CO. Very modest effective shear, and generally cool and dry low-levels will preclude severe potential. Late tonight, low-level warm advection is forecast across the southern Plains vicinity as weak cyclogenesis occurs over eastern CO in response to the approaching western CONUS shortwave trough. Boundary-layer moisture will remain modest, but increasing midlevel moisture, and steepening lapse rates should be sufficient for developing weak elevated instability through the -12 to -25 C layer. As such, a few lightning flashes are possible across parts of OK/KS after 06z tonight. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0107 PM CDT Mon Mar 20 2023 Valid 211200Z - 221200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 03/20/2023 .PREV DISCUSSION... /ISSUED 0151 AM CDT Mon Mar 20 2023/ ...Synopsis... Zonal flow aloft will trend more southwesterly with time over portions of the southern and central Rockies ahead of a deepening mid-level trough over the Desert Southwest. While not overly strong, a persistent lee cyclone should support gusty surface winds across much of the southern and central High Plains D2/Tuesday. Localized fire-weather potential may develop to the southwest of the surface low over portions of the southern High Plains. ...Southern High Plains... Broad southerly flow ahead of the surface low should gradually veer to southwesterly through the day across portions of the southern High Plains. Downslope trajectories and increased mixing from strengthening flow aloft ahead of the upper trough will favor some drying of the surface airmass. While to the east, returning Gulf moisture should keep humidity values above criteria, isolated pockets below 25% are possible across the TX/OK Panhandles and northeastern NM Tuesday afternoon. Wind gusts to near 20 kt may briefly overlap with the lower relative humidity, supporting a risk for some fire-weather concerns. However, uncertainty on the spatial and temporal overlap of dry and windy conditions remains high, suggesting the fire-weather threat will remain localized. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1138 AM CDT Mon Mar 20 2023 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Tuesday. ...Synopsis... On Tuesday, an upper low will move into central CA with a strong cyclonically-curved midlevel jet nosing into AZ and UT by 12Z Wednesday. Generally zonal flow conditions will prevail across the central and eastern states with high pressure over the East. Cold air aloft across the West will lead to areas of daytime thunderstorms from central and southern CA into the Great Basin. Weak instability is expected to preclude any severe storm threat. While the primary surface low will affect central CA and NV, a secondary low will develop over KS, with increasing low-level moisture return occurring from TX into OK. A leading/weaker wave and associated low-level jet will aid scattered elevated thunderstorms mainly from eastern KS into MO, but instability will be too weak for severe storms. Otherwise, the remainder of the warm sector across the southern Plains is to remain stable due to temporary warming aloft. ..Jewell.. 03/20/2023 Read more

No watches are valid as of Sun Mar 19 21:14:02 UTC 2023.

No Mesoscale Discussions are in effect as of Sun Mar 19 21:14:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0201 PM CDT Sun Mar 19 2023 Valid 192000Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today. No changes were made to the previous outlook with minimal thunderstorm chances across the CONUS. Isolated lightning flashes remain possible with activity near the FL Straits and perhaps into the Sierra where lift is maximized with minimal MUCAPE. ..Jewell.. 03/19/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Sun Mar 19 2023/ ...Synopsis... A mid-level trough will progress across the eastern CONUS as a second upper trough impinges on the West Coast today. Surface high pressure and associated subsidence and cooler temperatures will limit thunderstorm development across most of the CONUS through 12Z Monday. On exception would be offshore areas just south of the FL Keys, where a southward-sagging cold front continues to support few ongoing thunderstorms which are expected to gradually drift away from FL through the day. Another area that may see a couple of lightning flashes would be the higher terrain of the Sierra, where orographic ascent of deep low-level moisture and scant buoyancy may support convective snow potential through the period. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0114 PM CDT Sun Mar 19 2023 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 03/19/2023 .PREV DISCUSSION... /ISSUED 0153 AM CDT Sun Mar 19 2023/ ...Synopsis... Broad mid-level zonal flow is expected over much of the CONUS as the overall upper-air pattern deamplifys in the wake of the departing East Coast upper low. Transient ridging over the central US should weaken, allowing an area of high pressure at the surface to also weaken as it shifts eastward. Westerly flow over the Rockies will support increased lee troughing and dry southerly return flow across much of the Plains. ...Southern Plains... As surface high pressure over the central US weakens and shifts eastward, southerly return flow over much of the southern and central Plains is expected to develop on it westward flank. Aided by a deepening lee trough/developing surface cyclone, gusty southerly winds of 20-25 mph are possible. While not overly warm, the dry airmass will support afternoon RH values below 25% at times. The combination of gusty winds and lower relative humidity may support localized pockets of elevated fire-weather conditions through the afternoon. Primary uncertainty remains fuel availability and the duration of overlap with the dry/breezy conditions. For now, confidence in sustained fire-weather conditions remains too low for an Elevated area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1214 PM CDT Sun Mar 19 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected Monday. ...Synopsis... A large area of high pressure will encompass much of the central and eastern CONUS on Monday as an upper trough moves toward the East Coast. Behind this system, moderate west/northwest flow aloft will exist in the southern stream from southern CA into the Gulf of Mexico. Cool midlevel temperatures will exist over the Great Basin north of the jet axis, with daytime heating resulting in scattered weak thunderstorms. To the east, low pressure is forecast to develop over the central Plains overnight and into Tuesday morning, with a strong low-level jet response as the nose of the upper jet moves into the area. The result may be up to 100 J/kg of MUCAPE centered over parts of KS, and a few lightning flashes may result. ..Jewell.. 03/19/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Sun Mar 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 03/19/2023 .PREV DISCUSSION... /ISSUED 0151 AM CDT Sun Mar 19 2023/ ...Synopsis... In the mid levels, a broad cyclone over the East Coast will continue offshore with strong northwesterly flow in its wake across the eastern third of the CONUS. At the same time, mostly zonal flow will develop over the central CONUS. Stronger flow aloft will develop farther west ahead of a low-amplitude trough moving onshore across the West Coast. Much of the CONUS will remain post frontal at the surface, with relatively cool and stable conditions expected beneath a broad area of high pressure. However, as the high shifts south and east through the day, lee troughing will begin to support drier and windier conditions across portions of the southern High Plains this afternoon. ...Southern and central High Plains... On the fringes of the remnant post-frontal airmass across the central CONUS, gusty downslope winds and increasingly dry air are possible over portions of the High Plains. As the airmass is modified this afternoon, surface winds greater than 20 kt may overlap with afternoon RH values near or below 20% for a few hours across portions of northeastern NM, portions of eastern CO, and western KS. While some locally elevated meteorological conditions are possible, fuel conditions remains somewhat marginal given the recent freeze. The poor overlap of dry/windy conditions with receptive fuels suggests the fire-weather threat will remain localized this afternoon. However, should more widespread and longer duration fire-weather conditions appear more likely, a small Elevated area may be introduced in subsequent outlooks. ...Eastern US... Breezy offshore winds are possible today in the wake of the departing upper low off the East Coast. While somewhat drier than normal, winds are not expected to gust more than 15-20 mph with cool temperatures and RH values remaining near or above 30%. A few hours of locally elevated fire-weather conditions may develop over areas of drier than average fuels, but widespread fire-weather concerns are not anticipated. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sat Mar 18 21:14:01 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Mar 18 21:14:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0224 PM CDT Sat Mar 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast today. Little change was needed from the previous outlook as thunderstorm chances remain minimal across Florida. ..Jewell.. 03/18/2023 .PREV DISCUSSION... /ISSUED 1109 AM CDT Sat Mar 18 2023/ ...FL... A surface cold front is sagging southward across the FL Peninsula today. Scattered showers and thunderstorms may form along and ahead of the front this afternoon. However, the boundary has moved south of the primary westerlies aloft, and low-level frontal convergence has weakened. Therefore, storms that form should be limited in intensity and organization. Elsewhere across the CONUS, thunderstorms are not anticipated today. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0147 PM CDT Sat Mar 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... Dewpoints in the low single digits (F) are currently situated in parts of Nebraska and Kansas. This pocket of dry air is expected to remain in the region until the surface anticyclone shifts east Sunday. As this occurs, a belt of stronger southerly/southwesterly winds will develop from the Panhandles into western Kansas and Nebraska. Conditions often end up drier on the front end of southerly return flow. RH could fall to around 15% in some areas. Winds of 15-20 mph (with higher gusts) also look probable. The main question will be fuels. Available information suggests fuel dryness is generally marginal. Where fuels are locally drier, elevated fire weather could occur. Southwestern Kansas and nearby vicinity would be most favored for these conditions given the more limited precipitation that has occurred recently. ..Wendt.. 03/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CDT Sat Mar 18 2023/ ...Synopsis... Flow aloft is forecast to become more zonal D2/Sunday as a large upper cyclone weakens and departs the East Coast. The deamplifying flow pattern aloft will allow stronger westerlies to move south, intersecting portions of the southern and central Rockies. The increase in westerly flow will favor downslope winds and lee troughing. Surface high pressure will shift eastward and weaken allowing southerly winds of 15-20 kt to develop. The dry southerly return winds should begin to partially modify a cool and stable post-frontal airmass over the southern and central Plains. While occasionally gusty and slowly warming, the residual cooler airmass should keep diurnal relative humidity falls modest over much of the Plains. The poor overlap of dry and windy conditions with receptive fuels suggests the risk for significant fire-weather conditions is low through D2/Sunday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1204 PM CDT Sat Mar 18 2023 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Sunday. ...Synopsis... On Saturday, an upper low will be over southern Quebec with a positive-tilt trough extending southwestward toward the middle and lower MS Valley. A prominent surface high will be centered over the southern Plains and will spread eastward across the Southeast. This will result in cool and stable conditions for most areas. An exception may be far southern FL, where a cold front will exist during the day. Here, 60s F dewpoints and modest heating may lead to a few thunderstorms along the front. Severe storms are unlikely as winds below 500 mb will be quite weak. ..Jewell.. 03/18/2023 Read more

No watches are valid as of Fri Mar 17 21:17:02 UTC 2023.

No Mesoscale Discussions are in effect as of Fri Mar 17 21:17:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0203 PM CDT Fri Mar 17 2023 Valid 172000Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER THE FLORIDA PANHANDLE AND FAR SOUTHERN ALABAMA... ...SUMMARY... A few severe thunderstorms will be possible this afternoon across parts of the north-central/northeastern Gulf Coast region. Damaging gusts will be the main concern, and a tornado is possible. Little change was done to the existing outlook except to clear probabilities from behind the front. The air mass continues to slowly destabilize over the FL Panhandle, and a few severe storms will be possible from late afternoon into the evening. Hodographs will remain marginally favorable for supercells with either a brief tornado or locally damaging gusts with the stronger cells. ..Jewell.. 03/17/2023 .PREV DISCUSSION... /ISSUED 1112 AM CDT Fri Mar 17 2023/ ...Gulf Coast Region... A strong surface cold front and associated line of showers and thunderstorms is progressing eastward across southeast LA and southern MS. Convective intensity has been modest this morning, with relatively weak CAPE and cool surface temperatures being limiting factors. Visible satellite imagery shows partial heating occurring from Mobile Bay eastward, where temperatures will warm into the mid/upper 70s. Destabilization and steepening low-level lapse rates should result in some intensification and increasing risk of robust storms by mid-afternoon over southern AL, the FL panhandle, and southwest GA. Forecast soundings show relatively veered low-level winds and moderately strong westerly flow aloft. This may result in a few bowing structures capable of locally damaging wind gusts and perhaps a brief tornado or two. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0139 PM CDT Fri Mar 17 2023 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... The previous forecast is on track, and no changes are needed at this time. ..Supinie.. 03/17/2023 .PREV DISCUSSION... /ISSUED 0146 AM CDT Fri Mar 17 2023/ ...Synopsis... A broad mid-level cyclone, initially centered over the Great Lakes, is forecast to shift slowly northeastward into southeastern Canada through the forecast period. Accompanying the low, strong cyclonic flow aloft will dominate the eastern half of the CONUS, while weak ridging builds over the western US. At the surface, high pressure within a post-frontal airmass will favor weaker surface winds and much cooler temperatures over the central CONUS/Great Plains. With higher humidity, cooler temperatures and weakening winds expected, fire-weather concerns appear very low through D2/Saturday. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1137 AM CDT Fri Mar 17 2023 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely on Saturday. ...Synopsis... A large upper trough will encompass much of the eastern CONUS on Saturday with a deep upper low moving from the upper Great Lakes into southern Quebec. Strong southwest flow aloft will remain over the Southeast with a cold front extending from the eastern Atlantic into FL during the day. Heating ahead of this front combined with dewpoints in the 60s F may yield sufficient instability for a few weak thunderstorms. However, low-level flow will veer with time, and lift will be weak. Most of the activity is expected to remain over the Gulf of Mexico along the front, but a few storms are expected to threaten the Tampa Bay area, and perhaps eastward along the boundary toward the Cape. ..Jewell.. 03/17/2023 Read more