Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1055 AM CST Thu Jan 19 2023 Valid 191700Z - 201200Z ...NO CRITICAL AREAS... Dry/breezy conditions are possible across parts of AL into western GA behind an eastward-advancing cold front this afternoon. While sustained west-southwesterly surface winds around 15 mph (with gusts upwards of 30 mph) amid 30-35 percent RH would support elevated meteorological conditions, fuels should not be receptive to large-fire spread given early-day and recent precipitation. ..Weinman.. 01/19/2023 .PREV DISCUSSION... /ISSUED 0141 AM CST Thu Jan 19 2023/ ...Synopsis... A large area of low pressure will move through the Great Lakes today with windy conditions in proximity to the surface low. However cool and/or moist conditions will preclude fire weather concerns in this area. Dry conditions will be mostly confined to the southern High Plains where winds will be light. Therefore, fire weather concerns will be minimal today. ...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 1041 AM CST Thu Jan 19 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from the middle Texas Coast into southern Louisiana mainly late Friday night into Saturday morning. ...Synopsis... A prominent upper low will move across the Four Corners area and toward the central High Plains by 12Z Saturday, with a broad belt of strong mid to high level flow from the southern Plains to the Mid Atlantic Coast. At the surface, a stable air mass will exist due to high pressure extending from the Pacific Northwest across the Plains and into the northern Gulf of Mexico. Here, a stationary front will extend roughly from Brownsville TX to Tampa FL. Minimal northward progress of this boundary is forecast Friday night, with a stable surface air mass remaining along the immediate Gulf Coast. Rain is expected to expand in coverage across the middle to upper TX Coast during the afternoon as moistening occurs aloft, with very low chances of any lightning due to warm midlevel temperatures/poor lapse rates. The greatest potential for thunderstorms will exist overnight into southern LA. Here, forecast soundings show a few hundred J/kg MUCAPE rooted just above 850 mb, and while strong deep-layer shear will exist, poor lapse rates should preclude any severe hail threat. Elsewhere, scattered convective showers may occur over parts of the Four Corners region and across northern NM during the afternoon, as heating contributes to very weak instability beneath steep lapse rates aloft. However, sporadic flashes with this weak convection is expected to remain below the general thunderstorm outlook threshold. ..Jewell.. 01/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1022 AM CST Thu Jan 19 2023 Valid 191630Z - 201200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS WESTERN AND CENTRAL OHIO... ...SUMMARY... Low-topped thunderstorms are expected to develop over eastern Indiana and move rapidly east across Ohio this afternoon into early evening. Scattered severe wind gusts from 60-80 mph are most likely between 3 to 7 PM EST in western to central Ohio. ...Eastern IN and OH... A potent mid-level vorticity maximum over IL, embedded within the broader central CONUS trough, will eject east into OH through this evening. This feature will aid in sharpening an associated surface cold front that will rapidly progress east. Low-topped thunderstorms are expected to initiate across eastern IN towards early to mid-afternoon in a broken arc along the front. Within the exit region of an intense mid-level jet, this convection is expected to race east across OH through the afternoon. While SBCAPE will likely be meager, holding at or below 500 J/kg, nearly full insolation across the Lower to Middle OH Valley will yield steep 0-3 km lapse rates. This should support downward momentum transport of 50+ kt low-level winds as convection matures. Some 12Z HREF members (HRW-ARW, HRRR, and NAM-Nest) suggest boundary-layer max winds may reach 65-70 kts within rear inflow, supporting peak surface wind gusts across western to central OH. The arcing convective band will weaken after sunset as surface-based instability dwindles, but strong gusts may persist until convection dissipates in the western to central PA vicinity. ..Grams/Flournoy/Gleason.. 01/19/2023 Read more

WW 0024 Status Updates
STATUS REPORT ON WW 24 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 S LFK TO 30 WNW IER TO 15 SSW ELD TO 25 ENE ELD TO 35 NE LIT. ..FLOURNOY..01/18/23 ATTN...WFO...LZK...SHV...LCH...HGX... STATUS REPORT FOR WT 24 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC001-011-025-041-043-069-079-085-095-117-139-145-147-182040- AR . ARKANSAS COUNTIES INCLUDED ARE ARKANSAS BRADLEY CLEVELAND DESHA DREW JEFFERSON LINCOLN LONOKE MONROE PRAIRIE UNION WHITE WOODRUFF LAC013-027-031-049-061-069-073-081-085-111-115-127-182040- LA . LOUISIANA PARISHES INCLUDED ARE BIENVILLE CLAIBORNE DE SOTO JACKSON LINCOLN NATCHITOCHES OUACHITA RED RIVER SABINE UNION VERNON WINN TXC241-351-403-405-457-182040- Read more

WW 24 TORNADO AR LA TX 181500Z - 182200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 24 NWS Storm Prediction Center Norman OK 900 AM CST Wed Jan 18 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and southern Arkansas Northwest Louisiana East Texas * Effective this Wednesday morning and afternoon from 900 AM until 400 PM CST. * Primary threats include... A few tornadoes and a couple intense tornadoes possible Scattered damaging winds and isolated significant gusts to 75 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A few supercells should intensify within a broken band of thunderstorms from parts of east Texas into central Arkansas. This band should gradually shift east this afternoon. Primary threats are tornadoes and damaging winds. The tornado watch area is approximately along and 65 statute miles east and west of a line from 20 miles northeast of Little Rock AR to 35 miles south of Lufkin TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 22035. ...Grams Read more

MD 0073 CONCERNING WINTER MIXED PRECIPITATION FOR PORTIONS OF NORTHEASTERN KANSAS/SOUTHEASTERN NEBRASKA INTO SOUTHWESTERN IOWA AND FAR NORTHWESTERN MISSOURI
Mesoscale Discussion 0073 NWS Storm Prediction Center Norman OK 1253 PM CST Wed Jan 18 2023 Areas affected...portions of northeastern Kansas/southeastern Nebraska into southwestern Iowa and far northwestern Missouri Concerning...Winter mixed precipitation Valid 181853Z - 190000Z SUMMARY...Freezing rain and mixed precipitation with rates of 0.05-0.15 in/hr will continue with moderate precipitation over the next several hours. A transition to heavy snow and rates of 1+ in/hr is expected later this evening farther north. DISCUSSION...As of 1840 UTC, regional radar and surface analysis showed a broad area of moderate to heavy precipitation associated with a surface low across the central Plains and Midwest. Recent surface obs across southeastern NE and northeastern KS indicate freezing rain and mixed-phase precipitation is ongoing northeast of the surface low with rates of 0.05 to 0.15 in/hr. Area RAP soundings show moderate warm advection ongoing ahead of the low supporting broad isentropic ascent and slight warming in the 1-3 km layer. 0.5-1 C temperatures in this layer will support moderate to locally heavy mixed-phase precipitation and freezing rain for the next several hours. A transition to snow may develop later this afternoon into the early evening as warm advection weakens and dynamic cooling reduce column temperatures below freezing. However, the best dynamic lift will likely shift north keeping higher snow rates shorter in duration. Farther north across eastern/northern NE/IA, a deeper reservoir of cold air at the surface and drier mid-levels will likely favor a faster transition to all snow coincident with the strongest dynamic lift. Here, brief mixed precip/freezing rain and eventual snow rates greater than 1 in/hr are likely late this afternoon and through the evening hours. ..Lyons/Grams.. 01/18/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...EAX...OAX...TOP...GID... LAT...LON 40039530 39749594 39619684 39639768 39919834 40139842 40429836 40659827 40959793 41369696 42089558 42369492 42489370 42459321 42139263 41509299 41079345 40729402 40039530 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1247 PM CST Wed Jan 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes were made with this update. See the previous discussion below for details. ..Weinman.. 01/18/2023 .PREV DISCUSSION... /ISSUED 1258 AM CST Wed Jan 18 2023/ ...Synopsis... Moist conditions are expected across much of the eastern CONUS on Thursday with dry conditions across the southern Plains. However, winds will be light across this region which will preclude fire weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1247 PM CST Wed Jan 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes were made with this update. See the previous discussion below for details. ..Weinman.. 01/18/2023 .PREV DISCUSSION... /ISSUED 1258 AM CST Wed Jan 18 2023/ ...Synopsis... Moist conditions are expected across much of the eastern CONUS on Thursday with dry conditions across the southern Plains. However, winds will be light across this region which will preclude fire weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0072 CONCERNING SEVERE POTENTIAL...TORNADO WATCH LIKELY FOR NORTHEAST LOUISIANA...EAST ARKANSAS...WEST/NORTH MISSISSIPPI...AND FAR SOUTHWEST TENNESSEE
Mesoscale Discussion 0072 NWS Storm Prediction Center Norman OK 1230 PM CST Wed Jan 18 2023 Areas affected...northeast Louisiana...east Arkansas...west/north Mississippi...and far southwest Tennessee Concerning...Severe potential...Tornado Watch likely Valid 181830Z - 182000Z Probability of Watch Issuance...80 percent SUMMARY...The ongoing severe weather threat is expected to continue eastward this afternoon. Downstream watch issuance is likely. DISCUSSION...A broken line of convection with embedded supercell structures is ongoing across WW 24. These storms are evolving in an environment broadly characterized by modest MLCAPE (500-1000 J/kg) and favorable bulk shear (50-60 kts). A steadily clearing boundary layer ahead of the convection has yielded gradual warming, with surface temperatures in the low to mid 70s F across the region. This has steepened 0-3-km lapse rates slightly, which have increased to around 6 C/km per recent 17z/18z special soundings at SHV and JAN, respectively. Amidst broader moist advection, some boundary-layer mixing is evident in northeast Louisiana and west Mississippi with dewpoints dropping slightly to the low 60s F. This environmental evolution (along with ongoing convective patterns) is expected to yield continued, gradual upscale growth as the system progresses eastward. The primary threats should include a few tornadoes and isolated damaging wind gusts, mainly associated with any embedded supercells and/or more intense mesovortices within the broader convective line. ..Flournoy/Gleason/Grams.. 01/18/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...JAN...LZK...SHV... LAT...LON 34228948 33228995 32029087 31539164 31509250 31639290 31999272 32339244 32849216 33279197 33389147 33769119 34309094 34919100 35369087 35518983 35208938 34228948 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CST Wed Jan 18 2023 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WEST-CENTRAL INTO NORTH-CENTRAL OHIO... ...SUMMARY... Isolated to widely scattered severe gusts are possible from eastern Indiana through central and northern Ohio on Thursday afternoon to early evening. ...Synopsis... A mid-level low initially over northern MO will move east-northeast to the Lower Great Lakes by early Friday morning. An intense speed max (110 kt at 500 mb) will move through the base of a larger-scale trough. A cyclone over north-central IL will become occluded during the period as an attendant front sweeps east across the OH Valley and southern Appalachians/Southeast U.S. ...IN/OH... Scattered to widespread showers early Thursday morning in association with a warm-air advection will quickly depart the region by midday. The primary mid-level vorticity lobe will rotate through the base of the trough from the MS River on the MO/IL border east to the IN/OH border during the 15z to 21z period. Cold air advection in the mid levels coupled with some boundary layer heating (via gradual erosion of clouds and insolation) will act to weakly destabilize the airmass from eastern IN into OH. A cluster of low-topped convection will likely develop by early-mid afternoon over IN. Long hodographs indicate fast-moving storms and this activity will likely spread into northern OH by early evening. Severe gusts appear to be the primary severe hazard, but small to marginally severe hail and/or a brief/weak tornado cannot be ruled out. ...AL/GA... Model guidance continues to indicate a remnant band of convection will continue across the TN/AL/GA vicinity early in the morning. This band will likely weaken/dissipate by late morning as it continues to move into an airmass more hostile for deep convection. Nonetheless, scant instability may yield enough buoyancy for a few flashes of lightning and perhaps a strong gust. The overall threat appears too low to warrant low-severe probabilities at this time. ..Smith.. 01/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CST Wed Jan 18 2023 Valid 191200Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WEST-CENTRAL INTO NORTH-CENTRAL OHIO... ...SUMMARY... Isolated to widely scattered severe gusts are possible from eastern Indiana through central and northern Ohio on Thursday afternoon to early evening. ...Synopsis... A mid-level low initially over northern MO will move east-northeast to the Lower Great Lakes by early Friday morning. An intense speed max (110 kt at 500 mb) will move through the base of a larger-scale trough. A cyclone over north-central IL will become occluded during the period as an attendant front sweeps east across the OH Valley and southern Appalachians/Southeast U.S. ...IN/OH... Scattered to widespread showers early Thursday morning in association with a warm-air advection will quickly depart the region by midday. The primary mid-level vorticity lobe will rotate through the base of the trough from the MS River on the MO/IL border east to the IN/OH border during the 15z to 21z period. Cold air advection in the mid levels coupled with some boundary layer heating (via gradual erosion of clouds and insolation) will act to weakly destabilize the airmass from eastern IN into OH. A cluster of low-topped convection will likely develop by early-mid afternoon over IN. Long hodographs indicate fast-moving storms and this activity will likely spread into northern OH by early evening. Severe gusts appear to be the primary severe hazard, but small to marginally severe hail and/or a brief/weak tornado cannot be ruled out. ...AL/GA... Model guidance continues to indicate a remnant band of convection will continue across the TN/AL/GA vicinity early in the morning. This band will likely weaken/dissipate by late morning as it continues to move into an airmass more hostile for deep convection. Nonetheless, scant instability may yield enough buoyancy for a few flashes of lightning and perhaps a strong gust. The overall threat appears too low to warrant low-severe probabilities at this time. ..Smith.. 01/18/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Jan 18 2023 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SABINE AND LOWER MS/OH VALLEYS... ...SUMMARY... A few tornadoes and scattered damaging winds remain possible this afternoon from the Sabine Valley to the Mid-South, with more isolated coverage continuing into this evening across the Lower Ohio and Mississippi Valleys. ...Sabine and Lower MS/OH Valleys... Minimal change apparent for this outlook with a broken band of thunderstorms within the warm conveyor ahead of the eastern-moving cold front. The severe threat will likely peak this afternoon from the Sabine Valley into the Mid-South where 60s surface dew points (increasing to the southwest) supports MLCAPE of 500-1000 J/kg. The orientation and track of the shortwave trough over the central Great Plains suggests that mid-level lapse rates will weaken this afternoon, along with increasingly veered low-level flow diminishing hodograph curvature over the southern portion of the convective threat in TX/LA. This will likely maintain STP values in the 1-2 range this afternoon before diminishing later. A few tornadoes appear possible, with the damaging wind threat increasing some as the broken line consolidates into a broader QLCS. Confidence is decreasing with the longevity of an appreciable tornado and wind threat being maintained this evening. Bulk of morning CAM and machine-learning guidance are insistent on diminishing convective intensity towards 00Z, despite strengthening of the south-southwesterly low-level jet. Surface-based instability should eventually become pinched off in the Mid-South through eastern MS after sunset. This setup appears likely to yield a decreasing, but still a persistent low probability wind/brief tornado threat lingering tonight. ...Southeast KS... As the shortwave trough moves east across KS, a small corridor of opportunity for surface heating and steepening low-level lapse rates is possible near and east-southeast of the associated surface cyclone, beneath the mid-level dry slot. In the wake of morning rainfall, there may be scant MLCAPE approaching 250 J/kg. This could be barely adequate for a low-topped supercell with small to marginally severe hail and a brief weak tornado possible. ..Grams/Flournoy/Gleason.. 01/18/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Wed Jan 18 2023 Valid 181630Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SABINE AND LOWER MS/OH VALLEYS... ...SUMMARY... A few tornadoes and scattered damaging winds remain possible this afternoon from the Sabine Valley to the Mid-South, with more isolated coverage continuing into this evening across the Lower Ohio and Mississippi Valleys. ...Sabine and Lower MS/OH Valleys... Minimal change apparent for this outlook with a broken band of thunderstorms within the warm conveyor ahead of the eastern-moving cold front. The severe threat will likely peak this afternoon from the Sabine Valley into the Mid-South where 60s surface dew points (increasing to the southwest) supports MLCAPE of 500-1000 J/kg. The orientation and track of the shortwave trough over the central Great Plains suggests that mid-level lapse rates will weaken this afternoon, along with increasingly veered low-level flow diminishing hodograph curvature over the southern portion of the convective threat in TX/LA. This will likely maintain STP values in the 1-2 range this afternoon before diminishing later. A few tornadoes appear possible, with the damaging wind threat increasing some as the broken line consolidates into a broader QLCS. Confidence is decreasing with the longevity of an appreciable tornado and wind threat being maintained this evening. Bulk of morning CAM and machine-learning guidance are insistent on diminishing convective intensity towards 00Z, despite strengthening of the south-southwesterly low-level jet. Surface-based instability should eventually become pinched off in the Mid-South through eastern MS after sunset. This setup appears likely to yield a decreasing, but still a persistent low probability wind/brief tornado threat lingering tonight. ...Southeast KS... As the shortwave trough moves east across KS, a small corridor of opportunity for surface heating and steepening low-level lapse rates is possible near and east-southeast of the associated surface cyclone, beneath the mid-level dry slot. In the wake of morning rainfall, there may be scant MLCAPE approaching 250 J/kg. This could be barely adequate for a low-topped supercell with small to marginally severe hail and a brief weak tornado possible. ..Grams/Flournoy/Gleason.. 01/18/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0955 AM CST Wed Jan 18 2023 Valid 181700Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN PLAINS... The forecast remains on track, and no changes were needed to the ongoing Elevated or Critical areas. Visible satellite imagery late this morning shows clear skies over much of western/central TX and rapidly eroding clouds along the eastern edge of the Critical area (in the wake of the cold front). As a midlevel jet/dry-slot (evident in water vapor imagery) continues overspreading the risk area, efficient boundary-layer heating/mixing and strengthening westerly surface winds (sustained 25-30 mph with 35-40 mph gusts) are expected. These conditions will favor an expansive area of critical conditions across much of western and central TX this afternoon. For additional details, see the previous discussion below. ..Weinman.. 01/18/2023 .PREV DISCUSSION... /ISSUED 1258 AM CST Wed Jan 18 2023/ ...Synopsis... A strong mid-level trough will amplify as it crosses the central Plains today. A surface low will move from the TX/OK Panhandle into Missouri today with a cold front moving across eastern Oklahoma and Texas. In the wake of this cold front, dry and breezy conditions will develop as deep mixing commences beneath a very strong mid-level jet. Sustained winds of 25 to 30 mph are expected with relative humidity of 15 to 20 percent. ERC values are now around the 70-80th percentile and fine fuels remain dry and dormant. Therefore, a threat for large fires will exist across much of West and central Texas today. Dry and windy conditions will persist farther west into New Mexico, but temperatures will drop into the 40s across this region which will limit the fire weather threat. ...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 0955 AM CST Wed Jan 18 2023 Valid 181700Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN PLAINS... The forecast remains on track, and no changes were needed to the ongoing Elevated or Critical areas. Visible satellite imagery late this morning shows clear skies over much of western/central TX and rapidly eroding clouds along the eastern edge of the Critical area (in the wake of the cold front). As a midlevel jet/dry-slot (evident in water vapor imagery) continues overspreading the risk area, efficient boundary-layer heating/mixing and strengthening westerly surface winds (sustained 25-30 mph with 35-40 mph gusts) are expected. These conditions will favor an expansive area of critical conditions across much of western and central TX this afternoon. For additional details, see the previous discussion below. ..Weinman.. 01/18/2023 .PREV DISCUSSION... /ISSUED 1258 AM CST Wed Jan 18 2023/ ...Synopsis... A strong mid-level trough will amplify as it crosses the central Plains today. A surface low will move from the TX/OK Panhandle into Missouri today with a cold front moving across eastern Oklahoma and Texas. In the wake of this cold front, dry and breezy conditions will develop as deep mixing commences beneath a very strong mid-level jet. Sustained winds of 25 to 30 mph are expected with relative humidity of 15 to 20 percent. ERC values are now around the 70-80th percentile and fine fuels remain dry and dormant. Therefore, a threat for large fires will exist across much of West and central Texas today. Dry and windy conditions will persist farther west into New Mexico, but temperatures will drop into the 40s across this region which will limit the fire weather threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1201 PM CST Tue Jan 17 2023 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN PLAINS... Only minor adjustments were made to the outlook based on the latest high-resolution guidance consensus. In particular, the Critical highlights were expanded on the eastern and western edges slightly, where any early-day precipitation should be limited per the latest HREF QPF fields. With critical meteorological conditions expected over these areas, the expansion is warranted. Elsewhere, the previous forecast (see below) remains on track, with an expansive area of critical conditions expected over much of central and northwest TX. ..Weinman.. 01/17/2023 .PREV DISCUSSION... /ISSUED 0146 AM CST Tue Jan 17 2023/ ...Synopsis... A mid-level trough will amplify as it moves into the Plains on Wednesday. A lee cyclone will deepen across southeast Colorado and move along the Oklahoma/Kansas border during the day. The tightening pressure gradient will lead to strengthening surface winds across much of the southern Plains. The strongest winds are expected in the wake of the cold front, where deeper mixing is expected. Therefore, some stronger mid-level flow will reach the surface with sustained winds of 25 to 30 mph expected. In addition, this region is where the lowest relative humidity is expected, particularly directly behind the cold front where temperatures will remain somewhat higher initially. Additionally, the eastern extent of the threat will likely be mitigated by some precipitation which is expected Tuesday night/Wednesday morning. The eastern Elevated/Critical delineation is currently where wetting rain is most likely. However, this will likely change as the precipitation forecast becomes more clear. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Jan 17 18:03:02 UTC 2023.

No Mesoscale Discussions are in effect as of Tue Jan 17 18:03:02 UTC 2023.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CST Tue Jan 17 2023 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE MID-SOUTH AND SOUTHEAST... ...SUMMARY... Severe thunderstorms are possible from far east Texas and the Lower Mississippi Valley into the Tennessee and Lower Ohio Valleys on Wednesday. ...Synopsis... An upper-level trough will be in the process of ejecting into the southern Plains early Wednesday. This feature is expected to strengthen through the period. A mid-level jet of near 100 kts is expected to evolve within parts of the Mid-South and into the lower Ohio Valley. At the surface, a low pressure system will initially be located in southwestern Kansas. This low will move northeastward along with its parent trough. A secondary, weaker surface low is also forecast to develop in the lower Ohio Valley later in the day. A Pacific cold front will generally be the focus for convection across the Mid-South into the Southeast. Low to mid 60s F dewpoints are expected to advect northward ahead of the boundary as wind fields intensify. ...East TX...Lower/Mid MS Valley...TN Valley...Southeast... Some early convection appears possible in parts of the region, though modest capping should limit the overall extent of this early activity. Some guidance does depict more isolated/cellular activity ahead of the front by late morning. However, stronger cooling aloft will be offset from this activity and updrafts may struggle to maintain intensity. By the afternoon, stronger forcing and some surface heating will allow stronger storms to develop along the cold front. Lapse rates aloft are expected to be moderate (around 7-7.5 C/km) which will limit overall buoyancy to 500-1000 J/kg in most areas. Strong shear will support organized storms. Wind damage is expected to be the primary hazard, but a couple tornadoes also appear possible given the enlarged low-level hodographs present. Areas of eastern Arkansas/northwest Mississippi/western Tennessee will have the best overlap of buoyancy and forcing which could lead to a local maximum in wind damage potential. ...Lower Ohio Valley... Despite more limited instability/buoyancy, very strong wind fields at low/mid-levels will promote wind damage potential with strongly forced convection. The risk for wind damage will quickly drop off with northward/eastward extent. ...Parts of eastern Kansas... Very cold temperatures aloft will be present beneath the upper low. Moisture is expected to be quite limited and storm initiation is not certain. However, profiles would support some risk for at least small hail if convection can develop. ..Wendt.. 01/17/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1022 AM CST Tue Jan 17 2023 Valid 171630Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Discussion... A shortwave trough over the Lower CO Valley will deepen as it moves east across the southern Rockies into the southern/central High Plains by early morning, with a lee surface cyclone anchored over southeast CO before shifting into southwest KS late. Isolated thunderstorms will be possible this afternoon/evening within the zone of ascent preceding the shortwave trough, mainly over the Four Corners area. This regime will spread into the central Great Plains tonight, where scant elevated buoyancy should support sporadic lightning activity. Farther southeast, low-level warm theta-e advection should support elevated thunder potential late in the period in the eastern OK/northeast TX/western AR vicinity. An increasingly elongated, straight-line hodograph within the cloud-bearing layer does yield concern for hail production. While small hail looks plausible, meager buoyancy through 12Z will mitigate a severe hail highlight. ..Grams/Lyons.. 01/17/2023 Read more