Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1214 PM CST Mon Nov 28 2022 Valid 291200Z - 301200Z ...NO CRITICAL AREAS... The previous forecast reasoning (see below) remains the same, therefore, no changes/additions were made with this update. ..Weinman.. 11/28/2022 .PREV DISCUSSION... /ISSUED 1232 AM CST Mon Nov 28 2022/ ...Synopsis... A mid-level trough will traverse the Plains states while a rapidly deepening surface low ejects into the MS Valley tomorrow/Tuesday. As this occurs, a surface cold front will sweep southeastward across the Plains, while a dryline surges eastward across eastern New Mexico into western Texas tomorrow afternoon. Dry and windy conditions will accompany the post-dryline environment. These conditions would typically necessitate at least Elevated highlights. However, fuels remain marginally receptive (at best) to wildfire spread, and several guidance members suggest RH will struggle to drop below 20 percent by afternoon peak heating, precluding fire weather highlights this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Nov 28 18:17:02 UTC 2022.

No Mesoscale Discussions are in effect as of Mon Nov 28 18:17:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CST Mon Nov 28 2022 Valid 291200Z - 301200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR CENTRAL/NORTHERN MISSISSIPPI...NORTHEAST LOUISIANA...SOUTHEAST ARKANSAS...EXTREME SOUTHWEST TENNESSEE... ...SUMMARY... Severe thunderstorms capable of producing tornadoes and wind damage, along with some hail, are expected Tuesday afternoon and evening, extending into the overnight period across parts of the lower to mid Mississippi Valley and parts of the Southeast. A few strong/long-track tornadoes will be possible. ...Synopsis... A deep and progressive mid/upper-level trough is forecast to move from the central/southern Rockies eastward Tuesday morning to parts of the Mississippi Valley region by early Wednesday. A surface cyclone initially over central KS will move quickly northeastward toward the Upper Great Lakes by Tuesday evening, as an attendant cold front sweeps through the Great Plains and eventually into the Midwest. ...Lower/mid MS Valley into the Southeast... The potential for several long-track supercells remains evident across parts of the lower/mid MS Valley late Tuesday afternoon into Tuesday night, with a threat of strong tornadoes, scattered wind damage, and hail. Seasonably rich low-level moisture will quickly stream northward across the lower/mid MS Valley region ahead of the cold front on Tuesday, aided by a strong southwesterly low-level jet. Meanwhile, modestly steep midlevel lapse rates will overspread the region, in advance of the deep/progressive mid/upper-level trough. This will result in the development of moderate buoyancy (MLCAPE in excess of 1500 J/kg) across the warm sector. This destabilization will be occurring within a strongly sheared environment supportive of organized storms, including supercells. Initially elevated convection is expected to gradually increase in coverage through the morning across the ArkLaTex region within a low-level warm advection regime, with additional development possible farther south across southern LA/MS where somewhat stronger heating is expected. A few surface-based supercells are expected to evolve by afternoon, which could potentially be longer-lived as they move northeastward through a moistening and strongly sheared environment. Favorable 0-1 km shear/SRH will support a tornado threat, though some uncertainty remains regarding the impact of potentially weak low-level lapse rates on the tornado potential. Any sustained supercells within the warm sector could pose a strong tornado threat, in addition to a risk of hail and damaging gusts. Storm coverage will continue to increase through the evening and overnight hours, with favorable low-level moisture and strong low-level and deep-layer shear continuing to support a threat of all severe hazards. Some tornado potential is likely to continue overnight across parts of MS into western/central AL. ...Parts of the OH Valley/Midwest... Weaker low-level moisture return is expected farther north into parts of the Midwest and Ohio Valley in advance of the cold front. Despite weak buoyancy, favorable large-scale ascent and strong deep-layer flow could support a threat of locally damaging gusts with any sustained low-topped convection. There is some potential for a damaging wind threat to spread farther north than currently indicated, and some northward expansion of wind probabilities is possible depending on shorter-term observational and guidance trends. ..Dean.. 11/28/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1032 AM CST Mon Nov 28 2022 Valid 281700Z - 291200Z The only change with this update was to expand the current Elevated highlights northward along the I-25 corridor in southern CO. Here, mostly clear skies and strong downslope warming/drying should yield 15-20 percent RH this afternoon. In addition, strengthening westerly flow aloft (55-75-kt 3-6-km flow sampled upstream by GJT 12Z observed sounding) and a tightening pressure gradient will contribute to 15-20 mph sustained west-southwesterly surface winds (with gusts upwards of 40 mph). Given at least marginally receptive fuels through this corridor, the expansion is warranted. Elsewhere, the previous forecast (see below) remains on track. ..Weinman.. 11/28/2022 .PREV DISCUSSION... /ISSUED 1231 AM CST Mon Nov 28 2022/ ...Synopsis... A mid-level trough will deepen while traversing the Intermountain West today, encouraging surface lee troughing and associated downslope flow off of the Rockies into the southern High Plains. Dry and breezy conditions are likely for several hours this afternoon, with Elevated highlights introduced for portions of northeast New Mexico into the far northwestern Texas Panhandle. Here, the 15+ mph sustained southwesterly surface winds will overlap 15-20 percent RH and fuels that are at least marginally receptive to wildfire spread. ...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 1003 AM CST Mon Nov 28 2022 Valid 281630Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A thunderstorm or two may form around daybreak over parts of east Texas and western Louisiana. ...TX/LA... An upper trough is forecast to deepen rapidly later today and tonight across the southwest states, with low-level warm/moist advection strengthening after 06z over east TX. Forecast soundings suggest the mid-level capping inversion will be eroding through the overnight period, but it is uncertain whether deep convection will commence before or after 12z. Given the diversity of CAM solutions regarding this issue, will add a small thunderstorm forecast area for the last hour or two of the period to parts of east TX and western LA. No severe storms are expected until the Day2 period. ..Hart/Wendt.. 11/28/2022 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1225 PM CST Sun Nov 27 2022 Valid 281200Z - 291200Z The only change to the outlook was to introduce an Elevated area across parts of northeastern NM east-northeastward into the northwestern TX Panhandle -- where precipitation has generally been limited over the last 15-30 days. Despite increasing mid/high-level clouds, strengthening westerly flow aloft and related downslope warming/drying will favor a corridor of 15-20 percent RH during the afternoon. These dry boundary-layer conditions, coupled with 15-25 mph sustained west-southwesterly surface winds (with gusts upwards of 35 mph), will favor elevated to locally critical conditions. ..Weinman.. 11/27/2022 .PREV DISCUSSION... /ISSUED 1253 AM CST Sun Nov 27 2022/ ...Synopsis... Low-end fire weather concerns are possible across parts of the southern High Plains on Monday. Increasing mid to upper-level flow over the Rockies will yield a deepening lee trough along the central and southern High Plains. Westerly downslope winds are expected to increase to 15-25 mph from southern CO into northeast NM. Modest dry air advection coupled with downslope warming/drying will likely yield elevated fire weather conditions across this region. Despite reasonable confidence in 15+ mph winds and 15-25% RH, the overlap with receptive fuels is uncertain given recent precipitation and ERCs near to below seasonal average. Highlights may be introduced in subsequent outlooks based on fuel trends across portions of northeast NM, where 14-day rainfall has been minimal. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Nov 27 18:27:02 UTC 2022.

MD 1974 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR UPPER OHIO VALLEY
Mesoscale Discussion 1974 NWS Storm Prediction Center Norman OK 1119 AM CST Sun Nov 27 2022 Areas affected...Upper Ohio Valley Concerning...Severe potential...Watch unlikely Valid 271719Z - 271915Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong/damaging winds will be possible in parts of the upper Ohio Valley region this afternoon. DISCUSSION...Shallow convection has very slowly deepened along the cold front in southeast Ohio to near West Virginia border. A small region of mid 50s F dewpoints within this region is supporting 250-500 J/kg MUCAPE. Regional VAD profiles show 40-60 kts of flow within the lowest 2 km. Though convection will likely remain shallow and produce little lightning, isolated strong/damaging gusts will be possible as surface heating continues this afternoon. Within the last hour, a gust of 37 kts was observed near Chillicothe, OH and 47 kts was observed at Huntington, WV. Given the low-level inversions present on the 12Z observed ILM/PBZ soundings, low-level lapse rates are not expected to become overly steep even with more heating. The shallow convection will likely be the primary mechanism for stronger gusts this afternoon. ..Wendt/Hart.. 11/27/2022 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CTP...LWX...PBZ...RLX...ILN... LAT...LON 39818266 40428121 40717986 40387904 39897887 38758039 38378185 38558251 38808270 39818266 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CST Sun Nov 27 2022 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorm potential appears low on Monday. ...Synopsis... A surface cyclone is forecast to strengthen across the south-central High Plains on Monday, as a mid/upper-level trough deepens over the western/central CONUS. Most of the CONUS is expected to remain dry/stable through the day, though richer low-level moisture will begin returning to parts of TX/LA by early Tuesday morning, in conjunction with a strengthening low-level jet. Isolated lightning flashes cannot be entirely ruled out from Oregon into parts of the northern Great Basin, in association with a notable shortwave trough and mid/upper-level jet maximum moving southeastward out of the Pacific Northwest, but very meager buoyancy is expected to limit thunderstorm coverage. Elevated buoyancy will increase across parts of TX/LA late in the period as low-level moisture returns, but it currently appears that capping will remain sufficient to suppress deep convection through 12Z Tuesday. ..Dean.. 11/27/2022 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sun Nov 27 2022 Valid 271630Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF EASTERN NORTH CAROLINA...SOUTHEAST VIRGINIA...NORTHERN WEST VIRGINIA...AND SOUTHWEST PENNSYLVANIA... ...SUMMARY... Isolated severe thunderstorms are possible over parts of the Mid-Atlantic region this afternoon. ...Eastern NC/Southeast VA... Latest surface analysis shows a deep low over IL/IN, with an occluded front extending across OH then southward into the central Appalachians. A pre-frontal trough is developing over central NC. This trough may be the focus for scattered thunderstorm development this afternoon. Recent VADs and 12z CAM solutions show an intense mesoscale low-level jet (60-70 knots at 850mb) over central SC. This feature is associated with an area of showers and isolated thunderstorms east of CLT. As the wind max tracks northeastward, several model solutions suggest the potential for development of a few discrete storms over eastern NC and extreme southeast VA. It is unclear how much destabilization can occur prior to arrival of convection, which limits confidence in the severe threat. Therefore will maintain ongoing MRGL risk and low tornado probabilities. However, very strong shear profiles and weak-but-perhaps-sufficient CAPE could result isolated supercells and a tornado or two before activity moves offshore. ...Northern WV/southwest PA... The cold front over OH/KY is expected to surge northeastward this afternoon across northern WV and southwest PA. Forecast soundings in this area show very weak CAPE, but strong winds aloft and strong forcing. There remains some potential for a small fast-moving bowing line of shallow convection posing a risk of gusty/damaging wind gusts. Therefore have added a small MRGL risk area to cover this concern. ..Hart/Wendt.. 11/27/2022 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Sun Nov 27 2022 Valid 271700Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track, and no changes/additions were needed with this update. For details, see the previous discussion below. ..Weinman.. 11/27/2022 .PREV DISCUSSION... /ISSUED 1243 AM CST Sun Nov 27 2022/ ...Synopsis... Fire weather concerns will remain limited for today across the CONUS. A weakening upper low over the lower OH River Valley will continue to eject to the northeast through the day with a trailing cold front pushing east across the Southeast and Mid-Atlantic. To the west, flow aloft will gradually increase over the central/northern Rockies, as a wave approaching the Pacific Northwest deepens over the next 48 hours. This will support lee troughing along the central/northern High Plains, inducing strong downslope flow across central MT to southeast WY in the process. A few pockets of elevated fire weather conditions are possible in the lee of terrain features, but the overlap of elevated wind/RH and receptive fuels will likely remain too limited for highlights. Locally elevated conditions are also possible across the Big Bend region in southwest TX as winds increase ahead of a cold front. However, fuels across this region will likely not support fire spread. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No Mesoscale Discussions are in effect as of Sat Nov 26 17:55:02 UTC 2022.

No watches are valid as of Sat Nov 26 17:55:02 UTC 2022.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 26 2022 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorm potential is expected to be low on Sunday. ...Synopsis... A closed upper-low currently in the southern Plains will become more of an open wave on Saturday before quickly accelerating through the Mid-South and into the Mid-Atlantic and Northeast by late Sunday. A surface low is also expected to follow a similar track. Associated with this surface low, a cold front will progress through the Southeast Sunday morning into the afternoon. A secondary cold front will be present in the upper Midwest, moving eastward into the lower/middle Ohio Valley by later afternoon. ...Parts of Southeast into the Carolinas... Ongoing storms and precipitation along and ahead of the cold front are expected at the beginning of the period. This activity should serve to subdue diurnal heating and limit the development of more substantial buoyancy during the day. With mid-level ascent moving quickly to the northeast, potential for severe thunderstorms in parts of Georgia and north Florida will likely be limited. With slightly greater mid-level ascent, storm coverage in the Carolinas will likely be greater than areas to the south and west. Strong wind fields will be in place ahead of the cold front. Some conditional potential would exist for a strong/damaging wind gust and perhaps a brief tornado. However, the poor thermodynamics expected increases doubt as to the coverage of truly surface-based storms. ...Upper Ohio Valley... Precipitation is also expected to be ongoing early in the period. Model soundings do indicate some clearing is possible just ahead of the shortwave trough that will pass during the early/mid afternoon. Some moisture return ahead of the front may support some very low-topped convection. Due to the strong wind fields at low levels, some risk for a strong/damaging wind gusts will exist with this activity. However, confidence in sustained, stronger activity is low. ..Wendt.. 11/26/2022 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1025 AM CST Sat Nov 26 2022 Valid 271200Z - 281200Z ...NO CRITICAL AREAS... The forecast remains on track, and no changes/additions were made with this update. For details, see the previous discussion below. ..Weinman.. 11/26/2022 .PREV DISCUSSION... /ISSUED 0209 AM CST Sat Nov 26 2022/ ...Synopsis... Fire weather concerns will be limited Sunday across much of the CONUS. As the upper low over the southern Plains ejects across the OH River Valley region on Sunday, enhanced flow associated with the approach of a broad trough across the West will overspread the northern and central Rockies. A deepening lee trough along the High Plains will foster strong downslope winds from southern MT to southeast WY. Some pockets of downslope warming/drying may be sufficient to yield periods of elevated fire weather conditions. However, the spatial extent of these conditions remains uncertain as does the overlap with receptive fuels across the central Plains. ...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 1025 AM CST Sat Nov 26 2022 Valid 261700Z - 271200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track, and no changes/additions were needed with this update. ..Weinman.. 11/26/2022 .PREV DISCUSSION... /ISSUED 0132 AM CST Sat Nov 26 2022/ ...Synopsis... Fire weather concerns will remain low for today for much of the CONUS. Localized concerns may emerge across portions of the central Plains and southern California. ...Central Plains... Early-morning surface observations show a cold front beginning to move into parts of MT/ND. This front will continue to the southeast over the next 24 hours, resulting in breezy northwest winds across much of southern SD and NE where fuels are dry (ERCs in the 80-90th percentile range). Cool post-frontal air will limit overall RH reductions, but some areas may experience periods of 15-20 mph winds (gusting to 25 mph) with RH values between 20-25%. However, confidence in the duration/coverage of such conditions remains limited. ...Southern California... Poor overnight RH recoveries (RH values in the teens) are noted along the southern CA coast and interior terrain with a weak offshore flow regime in place. The development of a weak inland thermal low should favor weak onshore flow by this afternoon, but warm temperatures will maintain low RH. Pockets of elevated conditions will be possible for areas with terrain-enhanced winds as afternoon RH values fall into the teens and low 20s. ...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 1020 AM CST Sat Nov 26 2022 Valid 261630Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH EARLY TONIGHT FROM SOUTHEAST LOUISIANA TO THE FLORIDA PANHANDLE.... ...SUMMARY... There is a risk of a tornado or two and locally damaging winds this afternoon through early tonight from southeast Louisiana to the Florida Panhandle. ...Central Gulf Coast... A deep upper low is moving slowly eastward across TX today, with the primary surface low just off the coast of southeast TX. A warm front extends eastward from the low just south of the LA coast. Continued strong southerly low-level winds will help the warm front to move slowly northward today, allowing a very moist air mass to spread into the Delta region of southeast LA and coastal counties of MS/AL and the FL Panhandle. A persistent line of thunderstorms currently extending from the LCH area southward into the Gulf is moving slowly eastward. Several supercell structures have been noted with this line overnight and this morning, and the potential for rotating activity will continue through the afternoon and evening. Low-level shear profiles are quite strong, especially in vicinity of the surface warm front. Most of the severe threat should remain offshore. However, CAM guidance suggests a narrow zone where surface-based supercells and an attendant risk of tornadoes/damaging wind gusts may threaten coastal counties/parishes this afternoon through early tonight. Therefore have added a SLGT risk for this area. ..Hart/Bunting.. 11/26/2022 Read more

No watches are valid as of Fri Nov 25 17:59:02 UTC 2022.

No Mesoscale Discussions are in effect as of Fri Nov 25 17:59:02 UTC 2022.