Severe Storms

No Mesoscale Discussions are in effect as of Fri Dec 20 19:05:01 UTC 2024.

No watches are valid as of Fri Dec 20 19:05:01 UTC 2024.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1110 AM CST Fri Dec 20 2024 Valid 211200Z - 221200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected on Saturday. ...Synopsis... An upper-level ridge centered near the Continental Divide will translate slowly eastward through the day as a strong, compact, negatively-tilted mid-level trough moves into the Pacific Northwest. Across the eastern CONUS a trough will persist on Saturday with dry, offshore flow at the surface. The lack of low-level moisture will limit any thunderstorm potential across most of the CONUS. The only exception will be across the Oregon/northern California coasts where cooling mid-level temps over the relatively warmer ocean waters may result in some shallow instability and the potential for a few thunderstorms. The strong low-level jet (50 to 70 knots from 12Z to 18Z Saturday along the Oregon/northern CA coast) may result in some gusty winds, even where lightning is not present. However, overall, limited instability should mitigate any severe weather potential. ..Bentley.. 12/20/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1019 AM CST Fri Dec 20 2024 Valid 201700Z - 211200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 12/20/2024 .PREV DISCUSSION... /ISSUED 1256 AM CST Fri Dec 20 2024/ ...Synopsis... A large-scale trough will move from the OH Valley to the Northeast, while a midlevel ridge persists over the Intermountain West. This will maintain relatively cool post-frontal conditions across much of the central and eastern CONUS. Over the central High Plains, surface lee troughing may result in locally dry/breezy conditions, though fire-weather concerns will be minimal. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1010 AM CST Fri Dec 20 2024 Valid 201630Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe weather is not forecast across the contiguous United States through tonight. ...Synopsis... Shortwave trough currently moving through the Mid MS Valley is expected to continue cyclonically through the base of the mean upper troughing over eastern North America, which takes it off the Mid-Atlantic Coast late tonight. Another shortwave trough is expected in its wake over the Great Lakes this afternoon through tonight, while yet another shortwave trough drops southeastward through the northern Plains. This evolution will help maintain mean troughing across the central and eastern CONUS, with cold and stable low levels precluding thunderstorm development. Farther west, upper ridging will persist another much of the western CONUS. Some dampening is anticipated within the northwestern periphery of is ridging as a pair of shortwave troughs rotate around an upper low over the northwestern Pacific Ocean. Frontal band associated with the second of these waves should reach the northern CA coast early Saturday morning. Cold mid-level temperatures and related steep mid-level lapse rates may result in enough buoyancy for a few lightning flashes within this band. ..Mosier/Moore.. 12/20/2024 Read more

No watches are valid as of Thu Dec 19 18:46:02 UTC 2024.

No Mesoscale Discussions are in effect as of Thu Dec 19 18:46:02 UTC 2024.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1243 PM CST Thu Dec 19 2024 Valid 201200Z - 211200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 12/19/2024 .PREV DISCUSSION... /ISSUED 0205 AM CST Thu Dec 19 2024/ ...Synopsis... Fire-weather potential over the CONUS is low. Amplifying mid-level flow over the US will result in deep troughing over the eastern US and ridging to the west. A surface cyclone moving through the Midwest will drag a cold front across the central CONUS, eventually moving offshore over the East. High pressure with a much cooler air mass behind the front will favor cool and dry conditions. This will largely limit fire-weather concerns, as a poor overlap of strong winds and low humidity are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 2273 CONCERNING HEAVY SNOW FOR FAR SOUTHEASTERN MINNESOTA INTO WEST-CENTRAL WISCONSIN
Mesoscale Discussion 2273 NWS Storm Prediction Center Norman OK 0948 AM CST Thu Dec 19 2024 Areas affected...far southeastern Minnesota into west-central Wisconsin Concerning...Heavy snow Valid 191548Z - 191845Z SUMMARY...Areas of heavy snow with rates around 1" per hour to continue through the late morning. DISCUSSION...Bands of moderate to heavy snow are ongoing across portions of southeastern MN into west-central WI. The heaviest snow appears to be focused near the MN/WI/IA border where upper-level divergence from a mid-level shortwave is leading to greater forcing amid deep moist convergence. HREF guidance indicates that rates will come down into the afternoon as upper-level support shifts southward, before the backside of the low shifts across the region later in the afternoon/evening when rates may increase again. ..Thornton.. 12/19/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MKX...ARX...MPX... LAT...LON 44769223 44589279 44049233 43749159 43529082 43379004 43649010 44049035 44439087 44769223 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK Issued by 15th OWS Scott Air Force Base IL 1116 AM CST Thu Dec 19 2024 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 on Friday. ...Synopsis... An upper shortwave trough developing southeast over the northern/central Plains to the Mid-MS Valley will reinforce mean upper troughing over the eastern half of the CONUS on Friday. Strong surface high pressure will overspread the central U.S. while a cold front develops far south into the Gulf and offshore the Atlantic coast. This will leave a dry and stable airmass over much of the CONUS, and thunderstorm chances will be low. ..15_ows.. 12/19/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK Issued by 15th OWS Scott Air Force Base IL 1116 AM CST Thu Dec 19 2024 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected across the Lower 48 on Friday. ...Synopsis... An upper shortwave trough developing southeast over the northern/central Plains to the Mid-MS Valley will reinforce mean upper troughing over the eastern half of the CONUS on Friday. Strong surface high pressure will overspread the central U.S. while a cold front develops far south into the Gulf and offshore the Atlantic coast. This will leave a dry and stable airmass over much of the CONUS, and thunderstorm chances will be low. ..15_ows.. 12/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK Issued by 15th OWS Scott Air Force Base IL 1015 AM CST Thu Dec 19 2024 Valid 191630Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected through late afternoon across extreme southeastern Florida. ...Synopsis/Discussion... Florida is experiencing a weak cold-frontal passage moving southward through late afternoon. This in combination with short-wave trough approaching from the west, ample low-level moisture, and weak instability will result in isolated thunderstorms for a few hours. ..15_ows.. 12/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK Issued by 15th OWS Scott Air Force Base IL 1015 AM CST Thu Dec 19 2024 Valid 191630Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected through late afternoon across extreme southeastern Florida. ...Synopsis/Discussion... Florida is experiencing a weak cold-frontal passage moving southward through late afternoon. This in combination with short-wave trough approaching from the west, ample low-level moisture, and weak instability will result in isolated thunderstorms for a few hours. ..15_ows.. 12/19/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0952 AM CST Thu Dec 19 2024 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 12/19/2024 .PREV DISCUSSION... /ISSUED 0203 AM CST Thu Dec 19 2024/ ...Synopsis... Mid-level ridging over the western US is forecast to move eastward as the overall upper-air pattern becomes more amplified. High pressure over the Great Basin will move into the Rockies as a cold front moves south over the central US. Aside from some residual offshore flow over parts of southern CA, widespread fire-weather concerns are not expected. ...Southern CA... Offshore pressure gradients and the resulting surface winds are expected to gradually weaken early this morning as high pressure shifts eastward over the Rockies and Great Basin. While winds should generally weaken, some lingering, locally elevated fire-weather conditions may continue in the foothills of Los Angeles and Ventura Counties through the first half of the afternoon. Limited in spatial coverage and duration, fire-weather concerns are not expected to be widespread. Fire-weather concerns will end as onshore flow returns this evening. ...Central Plains... A moderately strong downslope wind event behind the deepening shortwave trough will allow for strong gusts of 30-40 mph across parts of eastern CO and western NE/KS this afternoon. However, these winds are only expected to overlap with cooler surface temperatures and moderately low RH for a few hours. While some locally elevated fire-weather conditions are possible, the lack of drier fuels and the limited overlap of dry/windy conditions should negate more widespread fire-weather potential. ...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 0952 AM CST Thu Dec 19 2024 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. ..Wendt.. 12/19/2024 .PREV DISCUSSION... /ISSUED 0203 AM CST Thu Dec 19 2024/ ...Synopsis... Mid-level ridging over the western US is forecast to move eastward as the overall upper-air pattern becomes more amplified. High pressure over the Great Basin will move into the Rockies as a cold front moves south over the central US. Aside from some residual offshore flow over parts of southern CA, widespread fire-weather concerns are not expected. ...Southern CA... Offshore pressure gradients and the resulting surface winds are expected to gradually weaken early this morning as high pressure shifts eastward over the Rockies and Great Basin. While winds should generally weaken, some lingering, locally elevated fire-weather conditions may continue in the foothills of Los Angeles and Ventura Counties through the first half of the afternoon. Limited in spatial coverage and duration, fire-weather concerns are not expected to be widespread. Fire-weather concerns will end as onshore flow returns this evening. ...Central Plains... A moderately strong downslope wind event behind the deepening shortwave trough will allow for strong gusts of 30-40 mph across parts of eastern CO and western NE/KS this afternoon. However, these winds are only expected to overlap with cooler surface temperatures and moderately low RH for a few hours. While some locally elevated fire-weather conditions are possible, the lack of drier fuels and the limited overlap of dry/windy conditions should negate more widespread fire-weather potential. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Tue Dec 17 2024 Valid 171630Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTHEAST TEXAS/SOUTHEAST OKLAHOMA TO WESTERN TENNESSEE... ...SUMMARY... Isolated strong to severe thunderstorms are possible tonight through early Wednesday morning across parts of northeast Texas and vicinity into western Tennessee. ...Synopsis... Gradual trough amplification will occur through the period across the Plains into the Midwest, as a shortwave trough digs from the central Rockies to the southern Plains tonight. At the surface, a weak cyclone should develop from the central High Plains to the Mid-South and lower OH Valley by early Wednesday morning. Greater low-level moisture, characterized by upper 50s to mid 60s surface dewpoints, is in place across parts of the ArkLaTex to northern MS along/south of a convective outflow boundary/front. This moisture is forecast to spread gradually northward through tonight ahead of the approaching shortwave trough. A separate cold front will spread east-southeastward over parts of the southern Plains and mid MS Valley/Mid-South this evening and overnight. ...Northeast Texas to Western Tennessee... Robust convective development will likely be delayed until near/after 05Z tonight, as low-level warm advection and large-scale ascent preceding the upper trough gradually overspread the warm sector. Even though steeper mid-level lapse rates should lag/remain generally north of the cold front, weak instability (around 500-1000 J/kg MLCAPE) should be present in a narrow corridor along and just ahead of the front. This instability will become weaker and more limited with northeastward extent into middle TN, with an ill-defined cutoff to isolated severe potential somewhere in the western to middle TN vicinity. Strengthening mid-level southwesterly flow with the amplifying upper trough will eventually move into the ArkLaTex and Mid-South, mainly after 06Z, in tandem with modestly enhanced low-level southwesterlies. Sufficient speed shear should exist to support some updraft organization, although the orientation of the deep-layer shear vector will be nearly parallel to the surface front. Thunderstorm mergers and interactions appear likely, with eventual upscale growth into a line anticipated as the cold front intercepts the greater low-level moisture, especially after 09Z. Isolated hail may occur with initial convective development, before strong to occasionally damaging winds become the main threat in the last few hours of the period with the line. A brief tornado cannot be ruled out. The overall severe threat should remain isolated due to the somewhat marginal thermodynamic environment. ..Gleason/Dean.. 12/17/2024 Read more

No Mesoscale Discussions are in effect as of Tue Dec 17 16:35:01 UTC 2024.

No watches are valid as of Tue Dec 17 16:35:01 UTC 2024.

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0954 AM CST Tue Dec 17 2024 Valid 171700Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF LOS ANGELES AND VENTURA COUNTIES IN SOUTHERN CALIFORNIA... No changes to the ongoing forecast. ..Wendt.. 12/17/2024 .PREV DISCUSSION... /ISSUED 0213 AM CST Tue Dec 17 2024/ ...Synopsis... Quasi-zonal mid-level flow is expected to quickly amplify as ridging develops over the western US today and tonight. Surface high pressure will quickly build over the Great Basin as a cold front moves eastward across the central US. The high pressure will allow for moderate offshore winds and a much drier air mass to move into portions of southern CA. The strong winds and low humidity will support elevated to critical fire-weather concerns over portions of southern CA. ...Southern California... Offshore winds are expected to develop this afternoon and intensify this evening, as high pressure builds over the Great Basin. Northeast surface winds of 25-35 mph are likely through the Santa Clara River Valley and Oxnard Plain by late this evening and into early D2/Wed. The intensifying downslope winds and the arrival of drier air overnight should allow for several hours of 10-15% RH across southern California. The overlap of low RH and strong winds should support several hours of elevated to critical fire-weather conditions across parts of Los Angeles and Ventura Counties. ...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 0954 AM CST Tue Dec 17 2024 Valid 171700Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF LOS ANGELES AND VENTURA COUNTIES IN SOUTHERN CALIFORNIA... No changes to the ongoing forecast. ..Wendt.. 12/17/2024 .PREV DISCUSSION... /ISSUED 0213 AM CST Tue Dec 17 2024/ ...Synopsis... Quasi-zonal mid-level flow is expected to quickly amplify as ridging develops over the western US today and tonight. Surface high pressure will quickly build over the Great Basin as a cold front moves eastward across the central US. The high pressure will allow for moderate offshore winds and a much drier air mass to move into portions of southern CA. The strong winds and low humidity will support elevated to critical fire-weather concerns over portions of southern CA. ...Southern California... Offshore winds are expected to develop this afternoon and intensify this evening, as high pressure builds over the Great Basin. Northeast surface winds of 25-35 mph are likely through the Santa Clara River Valley and Oxnard Plain by late this evening and into early D2/Wed. The intensifying downslope winds and the arrival of drier air overnight should allow for several hours of 10-15% RH across southern California. The overlap of low RH and strong winds should support several hours of elevated to critical fire-weather conditions across parts of Los Angeles and Ventura Counties. ...Please see www.spc.noaa.gov/fire for graphic product... Read more