Severe Storms

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1222 PM CST Thu Mar 02 2023 Valid 031200Z - 041200Z The previous forecast for the southern Plains (see below) remains on track, and only minor adjustments were made with this update. Farther east, very dry mid/upper-tropospheric conditions will remain in place over the FL Peninsula, where deep-layer southwesterly winds will strengthen ahead of an eastward-advancing low-pressure system. While modest low-level moistening is expected with the increasing southerly flow, efficient diurnal heating and deep boundary-layer mixing into the dry air aloft should yield 35-40 percent RH -- especially over central into eastern FL where temperatures should warm into the upper 80s. Currently, confidence in the overlap of 35-40 percent RH and 15-20 mph southwesterly surface winds (with higher gusts) is highest over the eastern half of the Peninsula from near Lake Okeechobee northward to Lake/Volusia Counties. Given receptive fuels through this corridor, Elevated highlights have been added. Spotty elevated conditions could also materialize over portions of northern and southern FL, though these conditions look too brief/localized for highlights at this time. ..Weinman.. 03/02/2023 .PREV DISCUSSION... /ISSUED 0136 AM CST Thu Mar 02 2023/ ...Synopsis... As a powerful upper-level wave and associated surface cyclone propagate through the Midwest, generally mild conditions will exist in its wake in the Central U.S. on Friday. This will temper the fire weather conditions across the Plains, except in portions of west and south TX where elevated fire weather threats may develop Friday afternoon. ...West TX... 15-20 mph westerly, downsloping winds are expected across the region on Friday. Along with daytime heating, this will contribute to gradually drying surface conditions during the afternoon. A continued dearth of precipitation will yield forecast ERCs around the 80th percentile, supporting fire spread. The Elevated area in portions of west TX highlights where these conditions should overlap on Friday afternoon. ...Portions of the Rio Grande River Valley... Post-frontal sustained winds around 15 mph are possible in portions of the Rio Grande River Valley in south TX. These post-frontal winds should be strongest in the morning and subside in the middle of the afternoon. Diurnal heating will yield relative humidities around 15-20% in the early afternoon, supporting brief, elevated fire weather conditions in the area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

Public Severe Weather Outlook
PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1039 AM CST THU MAR 02 2023 ...Severe thunderstorms expected over parts of the Select a General Area this afternoon and tonight... * LOCATIONS... North central and northeast Texas Central and southern Arkansas Southeast Oklahoma Northern Louisiana Northwest Mississippi Southwest Tennessee * HAZARDS... Widespread damaging winds, some hurricane force A few intense tornadoes Widespread large hail, some baseball size * SUMMARY... Severe thunderstorms with very large hail to the size of baseballs or larger, significant thunderstorm gusts to 75 mph, and a couple of strong tornadoes are likely from north Texas this afternoon into the ArkLaTex through tonight. Preparedness actions... Review your severe weather safety procedures for the possibility of dangerous weather today. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A watch means that conditions are favorable for severe thunderstorms over the next several hours. If a severe thunderstorm warning is issued for your area, move to a place of safety, ideally in an interior room on the lowest floor of a sturdy building. && Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1134 AM CST Thu Mar 02 2023 Valid 031200Z - 041200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM MIDDLE TENNESSEE AND CENTRAL KENTUCKY... ...SUMMARY... Severe thunderstorms capable of damaging wind gusts and a few tornadoes will be possible on Friday across parts of the Southeast into the Tennessee and Ohio Valleys. ...Synopsis... A negatively tilted shortwave trough is forecast to extend from the AR/OK border into LA early Friday morning. This wave is expected to eject quickly northeastward throughout the day, reaching the lower OH Valley by Friday afternoon and the Upper Great Lakes by Saturday morning. Very strong mid to upper flow will accompany this system, with over 100 kt at 500-mb throughout its southern periphery. Strong mass response will also foster a strong and broad low-level jet, with a large area of 60+ kt at 850mb preceding the wave from the Southeast across the TN Valley into the Mid/Upper OH Valley. A deepening surface low will move just ahead of this shortwave, as an attendant cold front sweeps eastward across the Southeast States and TN Valley. A broad warm sector characterized by 60s dewpoints will initially be in place ahead of this low and associated front. Severe thunderstorms are anticipated along this front as it moves eastward, with the highest severe potential anticipated from middle TN into central KY during the afternoon. ...OH and TN Valleys... The surface low will likely be centered near southeast MO/northeast AR early Friday morning, before then moving quickly northeastward through the Lower OH Valley while occluding. This will lead to a narrowing of the warm sector with eastern extent. Even so, at least low 60s dewpoints are anticipated ahead of the low and attendant cold front from western TN/KY through middle TN and central KY. Heating ahead of the line will be modest, but some limited buoyancy is still expected to develop, particularly during the afternoon across middle TN and central KY. Strong forcing for ascent is expected, with vigorous large-scale ascent augmented by ascent along the front and surface low. This buoyancy and ascent will be colocated with robust wind fields. These environmental conditions are expected to support thunderstorms capable of strong gusts, and potentially a few tornadoes. A linear mode looks most probable, although some guidance has begun to indicate the potential for a few discrete storms ahead of the line. As of now, the discrete scenario has not been given too much weight, due to limited surface-based potential ahead of the line. That being said, any discrete storms that mature would likely be supercellular. ...Southeast... Instability will be limited by warm temperatures aloft, with the main forcing for ascent displaced northwest of the region. Even so, robust wind fields and moderate low-level moisture are expected to support severe thunderstorms along a cold front moving quickly eastward across the region. Primary threat is damaging wind gusts, although a tornado or two is also possible. ..Mosier.. 03/02/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1059 AM CST Thu Mar 02 2023 Valid 021700Z - 031200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND SOUTH TEXAS... The previous forecast (see below) remains on track, and only minor westward expansions were made to the Elevated and Critical areas based on the latest observations and high-resolution guidance. Farther east over much of eastern and central FL, efficient diurnal heating/mixing amid a dry antecedent airmass should yield critically low RH (i.e., 30-35 percent) this afternoon. While sustained surface winds of around 10 mph or less should mitigate fire-weather concerns, at least locally elevated conditions are possible given dry fuels across the area. However, current thinking is that any elevated conditions should be too spotty for highlights. ..Weinman.. 03/02/2023 .PREV DISCUSSION... /ISSUED 0104 AM CST Thu Mar 02 2023/ ...Synopsis... A potent upper-level wave will eject across the Southern Plains during the day on Thursday. By the afternoon, a 100+ kt mid-level jet will overspread portions of west and south TX. This will support deep boundary-layer mixing and drying prior to the arrival of a Pacific cold front in the evening. Scattered convection yesterday has resulted in locally higher fuel moisture content. However, for the most part, the area has observed minimal precipitation for the past several days. These factors will contribute to critical fire weather conditions from the late morning through mid-afternoon in portions of central and south TX. ...Big Bend region, the Edwards Plateau, and portions of south-central TX... Critical fire weather conditions are expected to develop relatively early in the day as the powerful upper-level wave ejects eastward. By late Thursday morning (around 17z), a deepening surface cyclone centered in west-central TX will support strengthening west-southwesterly flow (25-30 mph) across the Big Bend region. Dry, downsloping winds will result in boundary-layer relative humidities around 10-15 percent. This area has experienced several days of minimal precipitation and generally dry, windy conditions, resulting in fuels that support large fire spread. The prior Critical area has been expanded into the Big Bend region and vicinity to account for these expected conditions starting early in the day. The expected area of critical conditions will gradually shift eastward throughout the afternoon. Its zonal area will be bounded by substantial moisture return to the east and an approaching Pacific front from the west. Some uncertainty in the timing of the front -- and associated quick reduction in elevated/critical fire weather conditions -- remains, but recent guidance suggest the most likely timing of passage through the Big Bend region should be around 19-21z. Thereafter, critical conditions should exist ahead of the front prior to nightfall through portions of south TX. Fuels are generally receptive to fire spread along the Rio Grande River Valley, except in a small area in south-central TX that experienced locally heavy convective precipitation yesterday. The Critical area has been trimmed slightly westward in this region, which would otherwise support a critical fire weather threat. ...southeastern NM... There is also some signal for the development of post-frontal, elevated fire weather conditions in southeastern NM in the afternoon. However, uncertainty regarding the timing of frontal passage, moisture quality behind the front, and somewhat less-receptive fuels preclude introducing an Elevated area there. ...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 1027 AM CST Thu Mar 02 2023 Valid 021630Z - 031200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT FOR NORTH CENTRAL TX INTO THE ARKLATEX... ...SUMMARY... Severe thunderstorms with very large hail to the size of baseballs or larger, significant thunderstorm gusts to 75 mph, and a couple of strong tornadoes are likely from north Texas into the ArkLaTex this afternoon through tonight. ...Synopsis... A compact midlevel shortwave trough will move over southwest TX later this afternoon, and then eject northeastward toward AR by the end of the period. Substantial surface cyclogenesis is expected in advance of the ejecting midlevel trough and 110+ kt midlevel jet streak, from north central TX later this afternoon to western/northern AR overnight. A reservoir of 65-72 F boundary-layer dewpoints is present from central/east TX into LA/MS as of late morning, and continued northward advection of moisture is expected through this afternoon into tonight. The north edge of the surface warm sector is not expected to move much to the north through this evening, with a front remaining quasi-stationary from north TX to southern AR. A remnant outflow boundary will tend to slowly become more diffuse through this afternoon across the DFW area. The approach of the midlevel trough, mass response to cyclogenesis, and surface heating in cloud breaks all suggest that thunderstorm development is probable by early-mid afternoon across central TX and western north TX, with storms spreading east-northeastward into the DFW area, northeast TX and extreme southeast OK through late evening. The initial storms will likely be clusters of supercells capable of producing very large hail and swaths of damaging winds as storms grow upscale into a line along the surging cold front from central into northeast TX this evening (some of which could produce significant gusts. Forecast hodographs also suggest some potential for tornadoes, including a strong tornado or two, though the most favorable wind profiles will correspond to tonight when storm mode will likely be more linear. The compact nature of the jet structure suggests that the stronger/deeper forcing for ascent will travel along the path of cyclogenesis, from far northeast TX/southeast OK into AR tonight. South of this area, ascent will be weaker and relatively warm temperature profiles aloft suggest that storm development is more questionable with southward and eastward extent across LA/MS overnight. ..Thompson/Thornton.. 03/02/2023 Read more

No watches are valid as of Wed Mar 1 20:24:02 UTC 2023.

MD 0215 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR ARKLATEX...SOUTH/CENTRAL ARKANSAS...NORTHERN MISSISSIPPI...AND WESTERN TENNESSEE
Mesoscale Discussion 0215 NWS Storm Prediction Center Norman OK 0222 PM CST Wed Mar 01 2023 Areas affected...Arklatex...South/Central Arkansas...Northern Mississippi...and western Tennessee Concerning...Severe potential...Tornado Watch likely Valid 012022Z - 012215Z Probability of Watch Issuance...80 percent SUMMARY...Severe storms are expected to develop and increase in coverage by the afternoon/evening. More discrete cells may pose risk of large hail and a few tornadoes. Tornado Watch likely needed by 21-22z. DISCUSSION...Current surface objective analysis and data from 18z soundings at SHV and LZK show some progress made in eroding CIN across the corridor from Louisiana, Arkansas, and Mississippi. However, daytime heating is well underway with surface obs showing temperatures across southern Louisiana and Mississippi approaching the upper 70s to lower 80s. Moisture is in place with mid to upper 60s dew points into central Arkansas and Tennessee. Trends within CAM guidance have been for development of more discrete cells initially across the Arklatex region by 21-23z, where the cap has been weakening within the last couple of hours. Once storms develop, initial discrete cells will be capable of large hail, given deep layer shear profiles of 60-65 kts. Any cells that can become surface based near the AR/LA border will support some risk for tornadoes given adequate low level shear. As the low level jet gradually strengthens late afternoon/evening, elongating shear profiles and increasing 0-1 km shear should support a greater risk for tornadoes. A Tornado Watch is likely by 21-22z. ..Thornton/Gleason.. 03/01/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...HUN...MEG...JAN...LZK...SHV... LAT...LON 34149458 34509434 34849311 34929245 35119181 35399067 35518946 35518847 35068818 34228838 33958868 33539063 33159273 33049352 33099421 33169470 33449477 33799475 34149458 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Wed Mar 01 2023 Valid 012000Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE ARKLATEX INTO THE MID-SOUTH... ...SUMMARY... A focused corridor of severe potential is evident this afternoon through tonight from northeast Texas into the Mid-South and Tennessee Valley. Scattered large to very large hail, damaging winds, and tornadoes all appear possible. A strong tornado may also occur. ...20Z Update... ...Northeast TX through the Mid-South and TN Valley... Recent surface analysis reveals a weak low over north Texas, with a stationary front extending northeastward across central AR into far southern IL. This front has been sharpening over the past few hours as warm, moist air advects northward across central/east TX and Lower MS Valley but cooler, drier trajectories persist through OK and the Ozark Plateau. 18Z SHV sounding still showed substantial capping, but the increased lift evidenced by the lightning activity across southeast OK and new echoes over southwest AR should begin to erode some of this inhibition. Thunderstorm development is still anticipated later this afternoon and evening. Highest tornado potential is still expected to occur within a narrow zone from southwest AR into northern MS and southwestern TN. In this area, a few discrete supercells are possible. Additional thunderstorm development is possible across the TX Hill Country early tomorrow morning and hail/wind probabilities were extended southwestward to cover this potential. ...NC... A few stronger thunderstorms are possible early tomorrow morning within the strengthening warm-air advection across the region. Buoyancy will be modest and storms should be elevated, but shear will be strong enough to support a few more robust/organized updrafts. Primary severe risk would be hail. Uncertainty regarding coverage precludes introducing any probabilities. ..Mosier.. 03/01/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Wed Mar 01 2023/ ...Southern Plains into the Mid-South and Tennessee Valley... A broad area of enhanced southwesterly mid-level flow will persist today through tonight across the southern Plains into the MS Valley and OH Valley. At the surface, a front extends from north TX into MO and the Midwest. Low-level moisture is forecast to gradually increase this afternoon and evening along/south of this boundary. A strong cap noted on the 12Z SHV sounding should inhibit robust convective development for at least a few more hours. Eventually, subtle large-scale forcing associated with a low-amplitude mid-level perturbation over TX, along with modest low-level convergence along the front, should support convective initiation over northeast TX/the ArkLaTex region by late this afternoon. Steep mid-level lapse rates, increasing low-level moisture, and filtered daytime heating should support moderate instability in a narrow corridor from northeast TX into the Mid-South. Deep-layer shear in excess of 50 kt will easily support organized thunderstorms, including supercells. Scattered large to very large hail will be threat with any initially discrete convection that develops. With time, thunderstorms should congeal into one or more bowing line segments as they spread eastward across the Mid-South and TN Valley this evening and tonight. The damaging wind threat should increase across these areas as this mode transition occurs. While there is still some uncertainty, most guidance also suggests that a southerly low-level jet will modestly strengthen this evening to around 30-35 kt. A narrow zone of more favorable tornado potential may exist across parts of southern/central AR into northern MS and southwestern TN, particularly if supercells can remain at least semi-discrete. A strong tornado appears possible in this corridor. Based on consensus of 12Z guidance, confidence has increased in a more concentrated corridor of severe potential across this region, warranting the addition of an Enhanced Risk. ...Ohio Valley... The cold front should advance quickly east-southeastward across the OH Valley through this evening. Low-level moisture will remain more limited compared to locations farther south. Still, steep lapse rates and ample daytime heating ahead of the front should aid in the development of weak instability this afternoon. Isolated strong to severe thunderstorms capable of producing both hail and damaging winds appear possible. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0117 PM CST Wed Mar 01 2023 Valid 021200Z - 031200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTH-CENTRAL TX AND THE RIO GRANDE VALLEY... The previous forecast remains valid with no changes. Widespread elevated and critical fire-weather conditions are expected across central and southern TX. More isolated and brief fire-weather potential will be possible for portions of North TX and the Red River Valley. Please see the prior discussion for more information. ..Lyons.. 03/01/2023 .PREV DISCUSSION... /ISSUED 0149 AM CST Wed Mar 01 2023/ ...Synopsis... A potent wave ejection over the Southern Plains is anticipated on D2/Thursday afternoon and evening. An attendant surface cyclone will rapidly deepen and propagate from eastern NM Thursday morning eastward into northeast TX by Thursday evening. Strong moisture advection will occur in advance of this cyclone, but its northwestward extent should be limited to portions of central TX throughout the day on Thursday. To the west, very strong flow aloft (around 100+ kt flow at 500 mb) will yield a very deep and well-mixed boundary layer in portions of south TX from the Edwards Plateau southward along the Rio Grande Valley. As a result, critical fire weather conditions are likely in these areas on Thursday afternoon. The duration of these conditions will be truncated by a Pacific cold front moving through the region in the evening. ...Portions of south TX... Strong boundary-layer mixing is anticipated early in the day on Thursday in portions of South TX. Sustained surface winds around 25-30+ mph and relative humidities around 10-15 percent are forecast as early as 17z. This will lead to a quick onset of critical fire weather conditions, particularly in western parts of the expanded Critical area. This region of very windy, dry conditions -- confined between an approaching cold front to the west and moisture return to the east -- will be relatively narrow and translate eastward during the day. Because of this, critical conditions will not be very long-lived in any particular region. The longest duration of critical conditions is expected in the Edwards Plateau vicinity before the arrival of a Pacific cold front around 20-22z. ERCs around the 80+ percentile are forecast in this area, indicating fuels receptive of large fire spread. Very strong surface flow around 40+ mph accompanying the frontal passage could pose a brief spike in the spread of any ongoing fire activity. However, milder conditions behind the front should thereafter quickly temper any further fire weather threat Thursday evening. ...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 1136 AM CST Wed Mar 01 2023 Valid 021200Z - 031200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST TX INTO SOUTHWEST AR AND NORTHWEST LA... ...SUMMARY... A regional severe-thunderstorm outbreak appears likely across parts of the southern Plains into the ArkLaTex and ArkLaMiss regions Thursday into Thursday night, with a few strong tornadoes, widespread damaging wind, and hail all expected. ...Synopsis... Upper low currently moving through central CA is forecast to continue southeastward today before then pivoting eastward tonight and reaching the AZ/NM border by early Thursday morning. Continued eastward progression across the southern High Plains is anticipated during the day Thursday. A trend towards a negative tilt and a bit more northeastward motion is expected Thursday night into Friday morning as the low moves across the southern Plains. Strong mid-level flow will accompany this system, with 100+ kt flow at 500 mb spreading eastward across TX Thursday afternoon and through the Arklatex by early Friday morning. Surface pattern will likely feature a weak frontal low over the TX Big Country early Thursday morning, with a warm front extending from this low northeastward through southeast OK and southern AR. Expectation is for this low to progress northeastward along the warm front into southeast OK by the afternoon, while a more substantial low develops farther west with the main ascent associated with the upper low. This primary low is then expected to move quickly eastward Thursday evening and overnight, as an attendant cold front sweeps across TX and the Lower MS Valley. ...Central/East TX into Lower MS Valley... Ample low-level moisture with surface dewpoints in the mid to upper 60s will be in place across the region ahead of the approaching upper low. Strengthening low to mid-level flow within this moist and buoyant environment will set the stage for numerous severe thunderstorms as the upper low moves through Thursday afternoon into Friday morning. Thunderstorms will likely be ongoing in the vicinity of the warm front from southwest TX through the Mid-South. A few stronger storms are possible within this corridor during the morning, but the primary severe threat is expected to begin over the warm sector Thursday afternoon. Wind profiles throughout the warm sector will support supercells, but warm mid-level temperatures and weak ascent introduce uncertainty regarding the location and coverage of any warm sector storms. Mesoscale ascent associated with the weak wave low mentioned in the synopsis may provide enough ascent to initiate a few discrete cells across northeast TX, which could then move downstream into southeast OK, southwest AR, and northwest LA. Persistent warm-air advection could also moisten the low to mid-levels just enough to initiate a few storms. Given the wind profiles, storms that mature should become supercells capable of all severe hazards, including very large hail, strong wind gusts, and tornadoes. A strong tornado is possible. A more widespread severe thunderstorm risk is expected to develop across southwest TX/TX Big Country during the late afternoon as the front moves through. Strong ascent along the front coupled attendant to the upper low should result in a line of severe storms. This line is forecast to move quickly eastward throughout the evening. Robust kinematic fields associated with strong mid-level flow and a strengthening low-level jet will support both strong wind gusts and embedded QLCS tornadoes with this squall line as it moves eastward. The same corridor most favorable for the afternoon discrete storms (i.e. from northeast TX into southern AR and northwest LA) will remain the most favorable for additional severe Thursday night. ..Mosier.. 03/01/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1032 AM CST Wed Mar 01 2023 Valid 011700Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NM AND WEST TX... The previous forecast remains valid with minor adjustments to the Critical area over the southern Rio Grande Valley. Widespread elevated and critical fire-weather conditions are expected from the TX Big Bend through West TX and the western TX Panhandle. Farther east in the Panhandle and western OK, a few hours of locally elevated fire-weather conditions may develop given low RH and gusty winds. However, cloud cover and rainfall from recent storms should keep the threat localized. Please see the prior discussion for more information. ..Lyons.. 03/01/2023 .PREV DISCUSSION... /ISSUED 0102 AM CST Wed Mar 01 2023/ ...Synopsis... A potent upper-level wave is expected to deepen on Wednesday over the western U.S. Surface low-pressure development will occur east of the Rockies around northeastern NM, yielding strengthening westerly winds in the Southern Plains throughout the day. A well-mixed, dry, and windy boundary layer will result. In tandem with these forecast meteorological conditions, lighter fuels receptive to large fire spread will yield a broad area of critical fire weather conditions across portions of the Southern Plains this afternoon. ...Portions of eastern NM and West TX... The strongly forced synoptic pattern -- downstream of a developing, potent upper-level trough -- is expected to yield quite dry and windy surface conditions in the Critical area. Sustained surface winds of 25-30 mph are expected along with relative humidities between 10-15%. Some areas with even drier conditions are possible (as low as 5%), especially where locally faster flow aloft (e.g., 80-90 kts at 500 mb) may support deeper mixing. Forecast ERCs are around the 60-80th percentiles, suggesting fuels support large fire spread. Localized wetting rain (around 1+ inch) occurred Sunday afternoon/evening in portions of the central TX Panhandle, where the Elevated area has been slightly trimmed. Otherwise, elevated to critical fire weather conditions are expected this afternoon in portions of eastern NM and West TX. ...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 Wed Mar 01 2023 Valid 011630Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE ARKLATEX INTO THE MID-SOUTH... ...SUMMARY... A focused corridor of severe potential is evident this afternoon through tonight from northeast Texas into the Mid-South and Tennessee Valley. Scattered large to very large hail, damaging winds, and tornadoes all appear possible. A strong tornado may also occur. ...Southern Plains into the Mid-South and Tennessee Valley... A broad area of enhanced southwesterly mid-level flow will persist today through tonight across the southern Plains into the MS Valley and OH Valley. At the surface, a front extends from north TX into MO and the Midwest. Low-level moisture is forecast to gradually increase this afternoon and evening along/south of this boundary. A strong cap noted on the 12Z SHV sounding should inhibit robust convective development for at least a few more hours. Eventually, subtle large-scale forcing associated with a low-amplitude mid-level perturbation over TX, along with modest low-level convergence along the front, should support convective initiation over northeast TX/the ArkLaTex region by late this afternoon. Steep mid-level lapse rates, increasing low-level moisture, and filtered daytime heating should support moderate instability in a narrow corridor from northeast TX into the Mid-South. Deep-layer shear in excess of 50 kt will easily support organized thunderstorms, including supercells. Scattered large to very large hail will be threat with any initially discrete convection that develops. With time, thunderstorms should congeal into one or more bowing line segments as they spread eastward across the Mid-South and TN Valley this evening and tonight. The damaging wind threat should increase across these areas as this mode transition occurs. While there is still some uncertainty, most guidance also suggests that a southerly low-level jet will modestly strengthen this evening to around 30-35 kt. A narrow zone of more favorable tornado potential may exist across parts of southern/central AR into northern MS and southwestern TN, particularly if supercells can remain at least semi-discrete. A strong tornado appears possible in this corridor. Based on consensus of 12Z guidance, confidence has increased in a more concentrated corridor of severe potential across this region, warranting the addition of an Enhanced Risk. ...Ohio Valley... The cold front should advance quickly east-southeastward across the OH Valley through this evening. Low-level moisture will remain more limited compared to locations farther south. Still, steep lapse rates and ample daytime heating ahead of the front should aid in the development of weak instability this afternoon. Isolated strong to severe thunderstorms capable of producing both hail and damaging winds appear possible. ..Gleason/Thornton.. 03/01/2023 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CST Tue Feb 28 2023 Valid 282000Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely through early Wednesday morning. ...20Z Update... Forecast outlined in the previous discussion (appended below) remains valid and no changes are needed. ..Mosier.. 02/28/2023 .PREV DISCUSSION... /ISSUED 1026 AM CST Tue Feb 28 2023/ ...Synopsis and Discussion... Cold mid-level temperatures and some steepening of lapse rates aloft associated with an upper trough digging over the West Coast may support isolated lightning flashes with low-topped convection occurring across parts of OR, northern/central CA, and the northern Great Basin through tonight. Meager instability should keep overall thunderstorm coverage quite sparse. A separate shortwave trough will advance northeastward today over the northern/central Rockies and adjacent High Plains. Low-level moisture is expected to remain quite limited over these regions. But, very cold mid-level temperatures and some diurnal heating may support weak surface-based instability and potential for isolated thunderstorms across parts of SD and vicinity, mainly this afternoon and early evening. Farther south, additional thunderstorm development may occur over parts of central TX near the end of the period (around 09-12Z), associated with gradually increasing low-level moisture/lift and glancing large-scale ascent. MUCAPE around 1000-1500 J/kg, steep mid-level lapse rates, and strong deep-layer shear will conditionally support some threat for hail with this elevated convection. However, most guidance continues to suggest that the appreciable hail risk should occur after 12Z Wednesday morning. Read more

No watches are valid as of Tue Feb 28 19:44:02 UTC 2023.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0114 PM CST Tue Feb 28 2023 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NM AND WESTERN/SOUTHWESTERN TX... The previous forecast remains on track with only minor adjustments to the Elevated area for the latest guidance. Widespread elevated and critical fire-weather conditions are expected with dry and windy conditions Wednesday afternoon. See the previous forecast for more information. ..Lyons.. 02/28/2023 .PREV DISCUSSION... /ISSUED 0151 AM CST Tue Feb 28 2023/ ...Synopsis... A potent upper-level trough is expected to dig southeastward during the next couple of days. By Wednesday afternoon, the trough should extend from NV through southern CA with broad south-southwesterly flow overspreading the Central and Southern Plains. Surface cyclone development is expected by 18z in the High Plains and deepen throughout the afternoon. Gusty and dry conditions are expected for the remainder of the afternoon and evening, yielding critical fire-weather conditions in regions that have observed a dearth of recent rainfall. ...Portions of southeastern NM and West TX... As the upper-level trough deepens and approaches the region on D2/Wednesday, meteorological surface conditions will strongly support fire attack and spread. Dry, downsloping flow around 25-30 mph is anticipated, with areas of sustained 30+ mph winds also likely. Forecast relative humidities as low as 5-10 percent are possible around 21-23z. These conditions -- amidst regions that have observed minimal precipitation in the last two weeks -- are expected to yield sustained critical fire-weather conditions Wednesday afternoon and evening in the delineated area. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0211 CONCERNING HEAVY SNOW FOR PARTS OF NORTHERN SOUTH DAKOTA AND SOUTH-CENTRAL/SOUTHEAST NORTH DAKOTA
Mesoscale Discussion 0211 NWS Storm Prediction Center Norman OK 1218 PM CST Tue Feb 28 2023 Areas affected...Parts of northern South Dakota and south-central/southeast North Dakota Concerning...Heavy snow Valid 281818Z - 282245Z SUMMARY...A band of snow is likely to develop within the North Dakota/South Dakota border vicinity. A combination of frontal ascent and convective enhancement will promote snowfall rates of around 1 inch per hour this afternoon. DISCUSSION...Light snowfall is evident within central/southeast North Dakota, likely associated with a mid-level boundary. Water vapor imagery shows a shortwave trough in the northern Rockies. Subtle areas of ascent are noted ahead of this trough, one of which is contributing to precipitation moving north/northeast from central South Dakota. With time, the approach of the trough should increase ascent along the mid-level boundary and lead to increased snowfall rates, primarily in parts of southern North Dakota. Visible satellite shows some convective elements embedded within the South Dakota precipitation and forecast soundings suggest cloud-top instability will be present into North Dakota as well. Snowfall rates of around an inch per hour are possible, particularly where some convective enhancement occurs. ..Wendt.. 02/28/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF...ABR...BIS... LAT...LON 45619951 45709993 45910070 46300141 46930158 47490061 47439871 46789794 46159768 45909768 45699813 45619951 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CST Tue Feb 28 2023 Valid 011200Z - 021200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE ARKLATEX ACROSS THE MID-SOUTH INTO MIDDLE TN... ...SUMMARY... Severe thunderstorms will be possible on Wednesday from northeast Texas through the Mid-South and into Middle Tennessee, with a threat of hail, damaging wind, and a couple of tornadoes. ...Synopsis... The strong shortwave trough currently just off the Pacific Northwest coast is expected to drop south through northern CA today, before then pivoting more eastward/southeastward as it moves from central CA through the southern Great Basin/Lower CO River Valley and AZ. By early Thursday, this shortwave, which will likely have matured into a closed low, is expected to be centered over the AZ/NM border. Enhanced southwesterly mid-level flow will precede this system, extending from the southern High Plains across much of the eastern CONUS. Most guidance indicates a low-amplitude shortwave trough will move through this southwesterly flow aloft, progressing from the southern High Plains through the southern and central Plains Wednesday. At the surface, a low will likely be centered over southwest MO. A cold front will extend southwestward from this low through eastern OK and north-central TX. This low is expected to progress northeastward through the OH Valley during the day, while the cold front remains largely stationary. This boundary will eventually begin returning northward Wednesday evening through Thursday morning as surface cyclogenesis occurs over the southern High Plains and the low-level flow increases across the southern Plains. ...North TX through the Arklatex into the Mid-South/TN Valley... Despite a notable mid-level dry layer, convergence along the front coupled with modest large-scale ascent attendant to the lead shortwave may result in isolated thunderstorms Wednesday morning over north-central TX. Primary threat with this activity would be hail. Timing and coverage varies within the guidance, precluding higher probabilities with this outlook. Farther east (from northeast TX/Arklatex into the Mid-South), thunderstorms are expected to develop in the vicinity of the front Wednesday afternoon into Wednesday evening, supported by lift from persistent low-level convergence and the subtle shortwave trough. Storm initiation appears most probable in the Arklatex with storms then potentially maturing across southern AR and far northwest MS. Long hodographs suggest splitting supercells capable of all severe hazards are possible with the mature warm sector storms, including very large hail and tornadoes. Modest ascent results in uncertainty regarding storm coverage within the warm sector. Greater storm coverage is anticipated north of the front, where hail will still be possible, particularly with early development. A trend towards a more linear mode, with one or more bowing segments, is expected over time along and north the front. Potential exists for these more linear storms to encounter less low-level stability farther with eastern extent, increasing the potential for damaging wind gusts from northern MS into Middle TN. ..Mosier.. 02/28/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1038 AM CST Tue Feb 28 2023 Valid 281700Z - 011200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NM AND WEST TX... ...Southern High Plains... The previous forecast remains valid with only minor adjustments. Portions of the eastern TX/OK panhandles and northwestern OK may experience locally elevated fire-weather conditions this afternoon. However, recent precipitation has tempered fuels such that confidence in sustained fire-weather concerns is low. The Elevated area was adjusted slightly northeast to cover area of more robust drying in the last 24 hours that may support a local risk of elevated fire-weather concerns. Cooler conditions will gradually develop behind a cold front expected to move south this evening and overnight. Please see the previous discussion for additional information. ..Lyons.. 02/28/2023 .PREV DISCUSSION... /ISSUED 1253 AM CST Tue Feb 28 2023/ ...Synopsis... Broad west-southwesterly flow aloft will yield warming temperatures and relatively dry conditions over portions of the central U.S. this afternoon. An embedded mid-level shortwave trough will traverse the Interior West from around 06-18z. Associated upward forcing -- along with enhanced cross-terrain flow -- will support surface cyclone development in eastern WY/CO and westerly flow across AZ/NM. Moisture will be limited in the wake of a cold frontal passage, yielding critical fire weather conditions across portions of the Southern Plains. ...Eastern NM and West TX... Downsloping trajectories across NM throughout the morning are expected to yield elevated/critical fire weather conditions by 1800-1900z early this afternoon. Sustained winds around 20+ mph amidst relative humidities around 15-20 percent are expected by this time. These conditions are expected to persist through 0000z with relative humidity reductions to 5-10 percent possible during that timeframe. Fuels remain slightly below normal in terms of initial attack and large fire spread. However, this region has experienced a recent lack of rainfall and sustained drying of fuels, especially in eastern portions of the Critical area, where forecast ERCs are around the 70-80th percentile. Some areas of the eastern TX/OK Panhandles and southwest KS received locally large amounts of rain (1-2 inches) in the last 48 hours, resulting in some trimming of the Critical area there. ...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 1026 AM CST Tue Feb 28 2023 Valid 281630Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely through early Wednesday morning. ...Synopsis and Discussion... Cold mid-level temperatures and some steepening of lapse rates aloft associated with an upper trough digging over the West Coast may support isolated lightning flashes with low-topped convection occurring across parts of OR, northern/central CA, and the northern Great Basin through tonight. Meager instability should keep overall thunderstorm coverage quite sparse. A separate shortwave trough will advance northeastward today over the northern/central Rockies and adjacent High Plains. Low-level moisture is expected to remain quite limited over these regions. But, very cold mid-level temperatures and some diurnal heating may support weak surface-based instability and potential for isolated thunderstorms across parts of SD and vicinity, mainly this afternoon and early evening. Farther south, additional thunderstorm development may occur over parts of central TX near the end of the period (around 09-12Z), associated with gradually increasing low-level moisture/lift and glancing large-scale ascent. MUCAPE around 1000-1500 J/kg, steep mid-level lapse rates, and strong deep-layer shear will conditionally support some threat for hail with this elevated convection. However, most guidance continues to suggest that the appreciable hail risk should occur after 12Z Wednesday morning. ..Gleason/Wendt.. 02/28/2023 Read more

WW 0047 Status Updates
STATUS REPORT ON WW 47 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SSW LUK TO 25 N LUK TO 25 W DAY TO 30 NNW DAY TO 35 E FWA AND 55 SE LUK TO 45 SSW CMH TO 35 SW CMH TO 35 ENE DAY TO 20 SW FDY. ..WENDT..02/27/23 ATTN...WFO...IWX...ILN...CLE... STATUS REPORT FOR WT 47 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OHC001-041-045-049-065-073-083-089-097-101-117-129-131-141-145- 159-272240- OH . OHIO COUNTIES INCLUDED ARE ADAMS DELAWARE FAIRFIELD FRANKLIN HARDIN HOCKING KNOX LICKING MADISON MARION MORROW PICKAWAY PIKE ROSS SCIOTO UNION THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more