Severe Storms

WW 0037 Status Updates
STATUS REPORT ON WW 37 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 WSW GLH TO 60 ENE PBF TO 25 SW DYR TO 35 N HOP. ..GOSS..02/16/23 ATTN...WFO...LZK...MEG...PAH...OHX... STATUS REPORT FOR WT 37 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC107-161740- AR . ARKANSAS COUNTIES INCLUDED ARE PHILLIPS KYC035-047-177-219-221-161740- KY . KENTUCKY COUNTIES INCLUDED ARE CALLOWAY CHRISTIAN MUHLENBERG TODD TRIGG MSC009-027-033-093-107-119-137-143-161740- MS . MISSISSIPPI COUNTIES INCLUDED ARE BENTON COAHOMA DESOTO MARSHALL PANOLA QUITMAN TATE TUNICA Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Thu Feb 16 2023 Valid 161630Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MIDDLE TN INTO MS AND AL... ...SUMMARY... Widely scattered severe thunderstorms are likely from the central Gulf Coast states northward into the Ohio Valley. Strong tornadoes are most likely over Mississippi, Alabama and middle Tennessee. ...Synopsis... A 1010 mb elongated surface low, currently positioned over the central MS Valley, should progress across the OH Valley through the day as a longwave upper-level trough continues to overspread the eastern CONUS. A strong low-level jet will overspread the TN/OH Valleys, roughly coinciding with a warm, moist and overall buoyant airmass across the Southeast. Deep-layer ascent in proximity to the low-level jet will supporting scattered to potentially widespread strong thunderstorms, several of which may be severe, particularly south of ongoing thunderstorms across the TN Valley. ...OH Valley... Widespread showers and thunderstorms are ongoing along the northern periphery of a gradually destabilizing warm sector, at the terminus of a 50 kt 850 mb jet. Continued low-level warm-air and moisture advection and increasing upper-support with the approaching mid-level trough will maintain the widespread nature of rain and thunderstorms through the afternoon, limiting diurnal heating and associated destabilization. As such, northern Category 1-2 (Slight-Enhanced) severe probabilities have been trimmed. Nonetheless, adequate low-level moisture, strong deep-layer ascent, and strong vertical shear profiles suggest that a conditional (low-end) damaging gust/tornado threat still exists as far north as the OH Valley, where Category 1/Marginal risk probabilities have been maintained. ...Middle TN into MS, AL, and far western GA... Relatively robust thunderstorm development has occurred well ahead of an approaching cold front in association with a confluence band along the LA/MS border area. Given ample diurnal heating, temperatures have warmed well into the 70s F, with upper 60s F dewpoint beginning to overspread central MS. With 7-8 C/km mid-level lapse rates overspreading this relatively pristine warm sector, 1000 J/kg MLCAPE should become common across the southeast, with patchy areas of 1500+ J/kg MLCAPE possible. 50+ kts of westerly 500 mb flow currently overlaps a 30-40 kt low-level jet, with ample speed increases/veering with height supporting 50+ kts of effective bulk shear, which will support supercell development through the afternoon given the aforementioned thermodynamic profile. Modest low-level elongation and curvature of hodographs (evident in mesoanalysis and regional VADs) suggest that storms that organize in the near-term could become tornadic supercells. However, the low-level jet should gradually shift northward from the warm-sector today, which is expected to temper hodograph length/curvature, serving as the primary reason for withholding a moderate risk upgrade this outlook. Nonetheless, an appreciable risk for tornadoes (a couple of which may be strong) necessitates the maintenance of Category 3/Enhanced probabilities, and a narrow corridor of locally higher tornado potential may briefly occur somewhere across eastern MS into central AL this afternoon. Thereafter, storms should gradually weaken as they cross into GA as buoyancy decreases and low-level winds continue to veer. ..Squitieri/Lyons.. 02/16/2023 Read more

No watches are valid as of Wed Feb 15 20:31:02 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Feb 15 20:31:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0127 PM CST Wed Feb 15 2023 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN ARKANSAS INTO WESTERN TENNESSEE AND NORTHERN MISSISSIPPI... ...SUMMARY... Severe thunderstorms with large hail are possible over parts of north Texas and southern Oklahoma this afternoon and evening. A threat for tornadoes, severe-thunderstorm winds and isolated hail will also develop overnight over the lower Mississippi Valley/Mid-South region. Little change was made to the previous outlook. Low-level moisture continues to increase across the southern Plains, although total precipitable water values remain quite low with the northern portion of the 50+ F dewpoints plume. Eventually, strong heating and continued moisture advection will lead to an uncapped air mass with scattered storms developing over western north TX into southern OK. Large hail will be the main concern, mainly after 00Z. Overnight, a tornado threat is expected to develop over eastern AR, northern MS, and western TN, beneath a strong low-level jet and with access to an instability plume extending southwest through the ArkLaTex. Effective SRH near 300 m2/s2 and MLCAPE over 1500 J/kg may support a strong tornado or two. ..Jewell.. 02/15/2023 .PREV DISCUSSION... /ISSUED 1032 AM CST Wed Feb 15 2023/ ...Synopsis... A closed upper low and attendant shortwave trough located over the Four Corners this morning will continue to shift east toward the southern Rockies and adjacent central/southern Plains through tonight. A lead shortwave impulse was noted in 15z water vapor imagery as of 15z ejecting over the southern Rockies in NM into the southern High Plains. Increasing ascent and a strengthening low-level jet associated with this feature will drive convective initiation by late afternoon/early evening across northern TX/southern OK. At the surface, strengthening cyclogenesis is expected to ensue over the next few hours across the southern High Plains. As this occurs, increasing southerly low-level flow will continue to transport Gulf moisture northward across the eastern half of TX into southeast OK, and eastward across the Lower MS Valley. A sharpening dryline/Pacific front oriented north to south from south-central OK into central TX, and a warm front lifting north of the Red River will focus initial thunderstorm development in the 21-00z time frame. ...Southern OK/Northern TX... Most guidance, including CAMs, initially develops supercells near the I-35 corridor in south-central OK/north TX in the 21-00z time frame. Modified forecast soundings for expected afternoon dewpoints near 60 F and temperatures in the mid/upper 70s indicate strong MUCAPE around 1500-2500 J/kg. Much of this instability is focused in the mid and upper levels of the sounding profile. Rapidly increasing and vertically veering winds with height are producing enlarged low-level hodographs, becoming elongated above 3 km. This thermodynamic and kinematic profile will favor initial supercell development. Furthermore, many significant hail sounding analogs are noted and hail in excess of 2 inches in diameter appears possible early in thunderstorm evolution. Deeper low-level moisture and a more established warm sector will remain somewhat east of this area. As a result, initial thunderstorms may have a higher LCL with some low-level dryness above the surface to around 1-1.5 km. This could enhance downdraft strength and also result in isolated to widely scattered damaging gusts as well. As a low-level jet increases after 00z, SRH values are forecast to increase from around 150 m2/s2 to over 250 m2/s2 and low-level moistening will increase with eastward extent. At this point, any semi-discrete convection will likely become more linear. Nevertheless, strong low-level shear and favorable 0-3 km hodographs will support rotation within embedded cells and mesovortices. ...Arklatex/East TX, to TN Valley/Mid-South... The severe threat will shift east across the Arklatex vicinity toward the Mid-South this evening into the overnight hours. Damaging gusts, isolated large hail, and tornadoes (a couple EF-2+ in strength) are expected. A more conditional severe threat will exist this afternoon/early evening across east TX into southern/central LA. Large-scale ascent will remain weaker across this area, and the surface front will remain well east of this area until late in the period. However, a quality warm sector will reside across this area with mid to upper 60s surface dewpoints expected. Low-level confluence and some influence on the margins of strong low/midlevel flow could support the development of a supercell or two. If this occurs, all severe hazards will be possible. However, this scenario remains uncertain and too conditional and will maintain a categorical Slight risk. Between 03-06z a southwesterly low-level jet will increase to 50-60 kt and overspread AR into northern MS and western TN, and eventually into KY and vicinity by 12z Thursday. Multiple bands/clusters of thunderstorms will be possible in low-level confluence within the northward developing low-level moisture plume. Embedded supercells will offer all severe hazards. The most favorable overlap of rich boundary-layer moisture and favorable low-level hodographs and SRH will exist across eastern AR into northwest MS/western TN vicinity after 00z. The tornado threat will be greatest across this area, with environmental parameter supporting the potential for a couple of significant tornadoes (EF-2+ intensity) in addition to damaging gusts. With northward extent, instability will become less toward western KY and vicinity later tonight. Nevertheless, strong shear and sufficient instability will support damaging wind potential into early Thursday morning. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1252 PM CST Wed Feb 15 2023 Valid 161200Z - 171200Z The forecast for elevated fire weather conditions tomorrow (D2/Thursday) in portions of South TX remains on track. A dry, cold frontal passage will occur through the area late tonight and early tomorrow morning. The region has experienced minimal precipitation in the last week, leading to fuel conditions supportive of an elevated fire weather threat. ..Flournoy/Bentley.. 02/15/2023 .PREV DISCUSSION... /ISSUED 0126 AM CST Wed Feb 15 2023/ ...Synopsis... A cold front is expected to move across the Southern Plains on Wednesday night, bringing much cooler temperatures and increasing dry northerly flow. Given recent rain and snowfall much of the fuels across the Southern Plains remain wet, which in addition to cooler temperatures will temper the fire weather risk across most areas. However, portions of Texas near the Rio Grande Valley that have remained dry will likely see Elevated fire weather conditions Thursday afternoon. Relative humidity reductions to around 20 percent and sustained northerly winds at 10-15 mph will be possible within this region, where ERCs are around the 60 percentile. As such, an Elevated fire weather risk has been introduced from South Central Texas into the Rio Grande Valley. ...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 1128 AM CST Wed Feb 15 2023 Valid 161200Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF MISSISSIPPI AND ALABAMA NORTHWARD INTO SOUTHWEST OHIO... ...SUMMARY... Widely scattered severe thunderstorms are likely from the central Gulf Coast states northward into the Ohio Valley on Thursday. Several tornadoes are possible over Mississippi and Alabama, including the risk for isolated strong tornadoes. ...Synopsis... An elongated positive-tilt upper trough will extend from the upper Great Lakes into the southern Plains by 00Z, with a primary/leading midlevel jet over 110 kt from MO into Lower MI and a dry slot developing from St. Louis to Lake Erie. After 00Z, a secondary wave will move from the southern Plains toward the lower MS Valley, with increasing height falls and strengthening winds aloft across the southeastern states. At the surface, low pressure will move from southern IL into OH by 00Z, reaching New England by Friday morning. A cold front will extend south from the low, crossing the MS River by late morning, and proceeding into the mid OH/TN Valleys by late afternoon. Meanwhile, a warm front will extend east from the low Thursday morning, across central IN and OH. Southerly winds across the warm sector will maintain a plume of 60s F dewpoints as far north as the surface low, with mid 60s F across the lower MS Valley. More substantial moisture will be in place over LA, with upper 60s F translating eastward across southern MS/AL and the FL Panhandle by Friday morning with the cold front roughly from western PA to FL by this time. A broad area of 40-50 kt southwesterly flow at 850 mb will exist atop the entire warm sector, enhancing low-level shear. The combination of a moist air mass and favorable shear over a large area will likely support corridors of severe storms, including a few tornadoes through the period. ...LA...MS...AL... A cold front will move into western MS and south-central LA by midday, where ample moisture will be in place. Storms both along and ahead of the front will be possible as the air mass will be uncapped, with upper 60s F dewpoints likely sufficient to support surface-based parcels. Effective SRH around 300 m2/s2 will be common along the eastern edge of the instability plume, and supercells will be possible with tornado risk. As height falls and winds aloft increase overnight, the cold front will continue to support strong to severe storms, with 50 kt flow at 850 mb and mid to upper 60s F dewpoints from southern AL into the FL Panhandle. Hodographs will be quite favorable for tornadic supercells, with the primary mitigating factor being cool/marginal boundary-layer temperatures. ...OH Valley into TN... Storms are likely to be ongoing across much of TN and KY, perhaps extending into northern MS and along the AR/MS border, within a warm advection regime beneath 50-60 kt 850 mb flow. The instability axis will be near the MS River Thursday morning, thus storms across western areas may have tornado or damaging wind potential at that time. Much will depend on existing storm modes at the beginning of the day, as heating will be limited, and outflow may both provide a focus for new development or stabilize portions of the warm sector. During the afternoon, areas of air mass recovery may occur ahead of the cold front and behind the early day storms. In addition, some of the existing storm complexes could evolve/reorganize across KY and TN. Shear profiles will strongly favor supercells with tornado threat, but little heating and ongoing precipitation may limit surface temperatures. Farther north, a dry slot should clear out much of the area around IL and northern IN, but southern IN into OH will remain sufficiently unstable for severe storms given strong shear. The area along and east of the surface low track may favor isolated supercells, assuming the surface air mass can warm into the mid 60s F. ..Jewell.. 02/15/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1032 AM CST Wed Feb 15 2023 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE MID-SOUTH REGION... ...SUMMARY... Severe thunderstorms with large to very large hail are possible over parts of north Texas and southern Oklahoma this afternoon and evening. A threat for tornadoes, severe-thunderstorm winds and isolated hail will also develop overnight over the lower Mississippi Valley/Mid-South region. ...Synopsis... A closed upper low and attendant shortwave trough located over the Four Corners this morning will continue to shift east toward the southern Rockies and adjacent central/southern Plains through tonight. A lead shortwave impulse was noted in 15z water vapor imagery as of 15z ejecting over the southern Rockies in NM into the southern High Plains. Increasing ascent and a strengthening low-level jet associated with this feature will drive convective initiation by late afternoon/early evening across northern TX/southern OK. At the surface, strengthening cyclogenesis is expected to ensue over the next few hours across the southern High Plains. As this occurs, increasing southerly low-level flow will continue to transport Gulf moisture northward across the eastern half of TX into southeast OK, and eastward across the Lower MS Valley. A sharpening dryline/Pacific front oriented north to south from south-central OK into central TX, and a warm front lifting north of the Red River will focus initial thunderstorm development in the 21-00z time frame. ...Southern OK/Northern TX... Most guidance, including CAMs, initially develops supercells near the I-35 corridor in south-central OK/north TX in the 21-00z time frame. Modified forecast soundings for expected afternoon dewpoints near 60 F and temperatures in the mid/upper 70s indicate strong MUCAPE around 1500-2500 J/kg. Much of this instability is focused in the mid and upper levels of the sounding profile. Rapidly increasing and vertically veering winds with height are producing enlarged low-level hodographs, becoming elongated above 3 km. This thermodynamic and kinematic profile will favor initial supercell development. Furthermore, many significant hail sounding analogs are noted and hail in excess of 2 inches in diameter appears possible early in thunderstorm evolution. Deeper low-level moisture and a more established warm sector will remain somewhat east of this area. As a result, initial thunderstorms may have a higher LCL with some low-level dryness above the surface to around 1-1.5 km. This could enhance downdraft strength and also result in isolated to widely scattered damaging gusts as well. As a low-level jet increases after 00z, SRH values are forecast to increase from around 150 m2/s2 to over 250 m2/s2 and low-level moistening will increase with eastward extent. At this point, any semi-discrete convection will likely become more linear. Nevertheless, strong low-level shear and favorable 0-3 km hodographs will support rotation within embedded cells and mesovortices. ...Arklatex/East TX, to TN Valley/Mid-South... The severe threat will shift east across the Arklatex vicinity toward the Mid-South this evening into the overnight hours. Damaging gusts, isolated large hail, and tornadoes (a couple EF-2+ in strength) are expected. A more conditional severe threat will exist this afternoon/early evening across east TX into southern/central LA. Large-scale ascent will remain weaker across this area, and the surface front will remain well east of this area until late in the period. However, a quality warm sector will reside across this area with mid to upper 60s surface dewpoints expected. Low-level confluence and some influence on the margins of strong low/midlevel flow could support the development of a supercell or two. If this occurs, all severe hazards will be possible. However, this scenario remains uncertain and too conditional and will maintain a categorical Slight risk. Between 03-06z a southwesterly low-level jet will increase to 50-60 kt and overspread AR into northern MS and western TN, and eventually into KY and vicinity by 12z Thursday. Multiple bands/clusters of thunderstorms will be possible in low-level confluence within the northward developing low-level moisture plume. Embedded supercells will offer all severe hazards. The most favorable overlap of rich boundary-layer moisture and favorable low-level hodographs and SRH will exist across eastern AR into northwest MS/western TN vicinity after 00z. The tornado threat will be greatest across this area, with environmental parameter supporting the potential for a couple of significant tornadoes (EF-2+ intensity) in addition to damaging gusts. With northward extent, instability will become less toward western KY and vicinity later tonight. Nevertheless, strong shear and sufficient instability will support damaging wind potential into early Thursday morning. ..Leitman/Lyons.. 02/15/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0954 AM CST Wed Feb 15 2023 Valid 151700Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR THE TX BIG BEND... The overall pattern continues to evolve as expected. The nose of an emerging mid-level jet was well sampled by the 12z EPZ sounding with 100+ kt flow around 500 mb. This will contribute to strengthening west-southwesterly downslope flow throughout the day and deep boundary-layer mixing across Far West TX. The Critical area has been extended slightly north toward the I-10 corridor and a bit eastward to account for a longer expected duration of 20+ mph surface winds in these areas. Extremely critical conditions are possible in the southernmost portions of the Big Bend where relative humidities could drop to around 5%; given the relative brevity of these conditions -- maximizing between 2000-2200 UTC -- a Critical area is maintained in this outlook. ..Flournoy/Bentley.. 02/15/2023 .PREV DISCUSSION... /ISSUED 1254 AM CST Wed Feb 15 2023/ ...Synopsis... A strong upper-level low currently located across the Great Basin will eject across the Plains on Wednesday featuring a strong southwesterly jet spreading into Texas and Oklahoma. As a result, a strong surface cyclone will develop across Colorado and Oklahoma before advancing eastward with an attending surface cold front. Strong westerly flow will develop across much of the Central and Southern Plains by the afternoon. Elevated to critical fire weather conditions will be possible, mainly across portions of far west Texas. Behind the dryline in central Texas, deep vertical mixing of strong flow and dry air will allow relative humidity reductions to 10-15 percent amid sustained winds of 20-30 mph. Much of the Texas Panhandle and northwestern Texas saw rainfall with the previous system where fuels remain largely above seasonal normals. Portions of far west Texas from Trans Pecos to the Edwards Plateau and southward have seen multiple rounds of dry and windy conditions with no recent rainfall. ERCs within this region are approaching the 60-80th percentile for dryness. The best overlap of dry fuels and Critical wind/relative humidity will be across Big Bend, where HREF probabilities show a high likelihood of sustained Critical fire weather conditions through the afternoon. A few isolated areas may briefly approach Extremely Critical, with winds sustained up to 30 mph and relative humidity at or below 10 percent. Given the more isolated/brief risk of Extremely Critical conditions, a Critical delineation has been maintained. Further northward into Trans Pecos and the Edwards Plateau, less receptive fuels preclude the need for a Critical delineation, but Elevated fire weather conditions will be possible. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Tue Feb 14 20:22:01 UTC 2023.

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Tue Feb 14 2023 Valid 151200Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF FAR WEST TX... ...Synopsis... An active weather pattern continues across the western and central CONUS. A shortwave mid-level trough -- currently centered over KS/OK -- is quickly propagating northeastward along with a 986 mb surface low in south-central KS. Widespread precipitation associated with this system has contributed to wetting rain (0.1-0.25") across portions of south-central TX and regions northeastward. A second, broader mid-level trough currently residing over western MT and ID is expected to propagate southeastward toward the Four Corners region by late afternoon/evening on Wednesday. Associated surface cyclogenesis and attendant dry, windy conditions will contribute to Critical fire weather conditions across the TX Big Bend on Wednesday. ...TX Big Bend... In association with the advancing mid-level trough, windy surface conditions are expected across much of West and northwest TX throughout the day on Wednesday. Broad areas of 20-30+ mph winds are anticipated, and localized areas of 30-40 mph are possible. The greatest overlap between strong surface flow and dry conditions is expected in portions of Far West TX -- particularly in the Big Bend region -- in association with downsloping flow. This region has experienced multiple days of dry and windy conditions along with a dearth of recent rainfall. This will lead to forecast ERCs near the 80th percentile that, along with the expected meteorological conditions, supports a broad Elevated area across Far West TX. In the TX Big Bend, a longer-duration period of 20+ mph flow amidst relative humidities in the teens is anticipated, warranting the maintenance of a Critical area there. ..Flournoy/Bentley.. 02/14/2023 .PREV DISCUSSION... /ISSUED 0148 AM CST Tue Feb 14 2023/ ...Synopsis... On Wednesday, a strong upper-level wave will eject out of the southwest with mid-level flow around 100 kts overspreading the Southern Plains. A surface low will deepen and move eastward with attendant surface cold front. Behind the dryline across central Texas, deep vertical mixing will allow for relative humidity reductions into the teens with sustained surface winds around 25-30 mph (gusting up to 40-50 mph). Given multiple days of dry and windy conditions and a lack of recent rainfall, Elevated to Critical fire weather will be possible across portions of western Texas. ERCs forecast to be near the 80th percentile and potential for relative humidity to drop to around 10 percent have warranted the inclusion of a Critical delineation for Big Bend. Further north within the Elevated delineation, fuels remain less receptive to fire spread with ERCs above seasonal normals. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0142 PM CST Tue Feb 14 2023 Valid 142000Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN KANSAS INTO WESTERN MISSOURI... ...SUMMARY... A few strong to severe thunderstorms are possible, mainly from eastern Kansas into western Missouri this afternoon and early evening. Little change was done to the previous outlook. Scattered low-topped thunderstorms, a few strong to severe, are expected to increase over eastern Kansas this afternoon, and move into western Missouri by early evening. For more information see mesoscale discussion 147. ..Jewell.. 02/14/2023 .PREV DISCUSSION... /ISSUED 1016 AM CST Tue Feb 14 2023/ ...Eastern KS this afternoon to northern IL tonight... In response to upstream amplification of a midlevel trough over the Great Basin, a downstream shortwave trough over western KS/OK this morning will eject northeastward over MO/IA/IL by early tonight. In the wake of morning rain/clouds, surface heating will contribute to steepening of low-level lapse rates across central/eastern KS this afternoon. Residual boundary-layer dewpoints in the mid-upper 40s and surface temperatures in the mid 50s, beneath 500 mb temperatures close to -25 C, will result in MLCAPE of 250-500 J/kg by mid afternoon across eastern KS. The environment will support low-topped thunderstorm development by mid afternoon in a loose arc or small clusters from south central into eastern KS, immediately in advance of the primary midlevel vorticity center, and on the nose of the steeper low-level lapse rates and drying from the southwest. Forecast soundings show sufficient buoyancy and hodograph length/curvature for some threat of low-topped supercells, with attendant threats for a tornado or two, isolated large hail, and damaging outflow gusts through late afternoon/early evening into west central/northwest MO. This scenario will be quite sensitive to the degree of vertical mixing, with small changes in moisture potentially driving outcome possibilities ranging from no severe to SLGT risk. Some form of the afternoon storm cluster may persist into tonight while spreading northeastward from MO into northern IL. Gusty winds will be possible early tonight with lingering, low-topped convection, but very marginal thermodynamic profiles suggest that severe gusts are unlikely. Read more

MD 0147 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR CENTRAL AND EASTERN KANSAS INTO PORTIONS OF SOUTHEASTERN NEBRASKA...NORTHWEST MISSOURI AND FAR SOUTHWESTERN IOWA
Mesoscale Discussion 0147 NWS Storm Prediction Center Norman OK 0140 PM CST Tue Feb 14 2023 Areas affected...Central and eastern Kansas into portions of southeastern Nebraska...northwest Missouri and far southwestern Iowa Concerning...Severe potential...Watch unlikely Valid 141940Z - 142145Z Probability of Watch Issuance...20 percent SUMMARY...Isolated low-topped thunderstorm development is expected in the next 1 to 2 hours across portions of central Kansas. Damaging wind gusts, a brief tornado or two and small hail will be possible with any sustained supercells. Conditions will be monitored but a weather watch is unlikely. DISCUSSION...As of 1930 UTC, afternoon moisture-channel imagery showed a mature upper low centered over southwestern KS. At the surface, strong southerly flow was noted east of a subtle dryline/surface trough southeast of sub 990 mb surface low. Over the last several hours, a mid-level dry slot has allowed for robust diurnal heating of a partially modified Gulf airmass characterized by surface dewpoints in the mid to upper 40s F. While not especially moist, mid-level temperatures of -25 C and steep 0-3 km lapse rates were supporting low-level MLCAPE on the order of 500 J/kg. Gradual deepening of a cumulus field has been noted suggesting residual inhibition is quickly diminishing. Continued heating, low-level convergence and dynamic ascent from the passing upper-level low should allow for isolated storm development beneath the cold core in the next couple of hours. Area RAP soundings show elongated low-level hodographs and adequate buoyancy (500-600 J/kg MLCAPE) to potentially support an isolated low-topped supercell from central KS northeastward toward southeastern NE, northwestern MO, and far southwestern IA. Steep lapse rates below 3 km, along with strong gradient winds and the modest surface moisture may support a risk for a few damaging gusts. A brief tornado or two along with isolated small hail may also be possible given 0-1 km shear in excess of 20 kt. Hi-res guidance suggests the localized severe threat may continue northeastward as the airmass rapidly modifies over the next few hours. Conditions will be monitored, but uncertainty on storm coverage and severity suggests the potential for a weather watch is low. ..Lyons/Thompson.. 02/14/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...EAX...OAX...TOP...ICT... LAT...LON 39719453 38779506 38379523 37909548 37639564 37389593 37259636 37249670 37409690 37679712 37979735 38519763 38909769 40059723 40589643 40929558 40789466 40369428 39719453 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CST Tue Feb 14 2023 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE LOWER MISSISSIPPI VALLEY...AND INTO PARTS NORTHEAST TEXAS AND SOUTHEAST OKLAHOMA... ...SUMMARY... Widely scattered severe thunderstorms are possible over parts of Texas and Oklahoma beginning late in the day and into the evening on Wednesday. A severe threat will also develop overnight over the lower Mississippi Valley, with tornado risk. ...Synopsis... An upper trough will become positively tilted as it moves east from the Four Corners to the Plains through Thursday morning, with an elongated speed max extending from the base of the trough from the southern Plains across the lower MO Valley and toward Lake Michigan late. Ahead of the trough, an upper high will remain over the Bahamas, with rising heights through 00Z across much of the Southeast. At the surface, low pressure will translate east from NM into OK through 00Z, ahead of a cold front which will surge south into the OK/TX Panhandles. This low is not forecast to deepen, but will continue northeastward ahead of the cold front to the Ozarks by 06Z and lower OH Valley by 12Z Thursday. Southerly surface winds will aid low-level moisture return during the day, with mid 60s F dewpoints common by 00Z over eastern TX and the lower MS Valley. Low 60s F dewpoints are eventually expected to reach the lower OH River/western KY by 12z Thursday, with the more substantial moisture from about Memphis south. Strengthening 850 mb winds over 40 kt will aid moisture transport, with modest instability and strong shear aiding severe potential from TX to the lower MS Valley, primarily after 00Z. ...Northeast TX...southeast OK into western AR... Heating will occur over OK and TX ahead of the cold front and south of the low, steepening lapse rates. Eventually, persistent southerly winds will bring low 60s F dewpoints to the Red River, most likely near or after 00Z. Modestly cool midlevel temperatures and convergence along the front may then be enough to break the cap, resulting in a few severe storms. Supercell wind profiles will exist, favoring large hail. Should the boundary layer moisten sufficiently, a tornado risk could develop. Much of this area appears conditional given mixed CAM signals, late moisture return, relatively late time of day (evening) and potential for capping. In addition, various forecast soundings indicate subsidence in the midlevels. However, stronger heating near the boundary coupled with late moisture return should result in at least isolated storms with hail. ...LA...MS...eastern AR...western TN... Rapid moistening of the boundary layer during the day is expected to lead to clouds and keep temperatures relatively cool. This should minimize the potential for convection through 00Z as a capping inversion will exist at or below 700 mb. Rain and thunderstorms are likely to develop after 03Z over much of AR, northern MS, and western TN, as dewpoints rise into the mid 60s F beneath a 50 kt low-level jet core. After about 06Z, a plume of > 1000 J/kg SBCAPE is forecast to extend from LA into eastern AR, gradually shifting into northwest MS and perhaps western TN. As such, it is possible that initially elevated convection transitions to surface based, which would increase the risk of isolated tornadoes. Better lift along the cold front could become a more favorable focus for supercells with tornado threat into Thursday morning. In general, the lack of a substantial baroclinic zone may mitigate the overall severe risk for much of the period, given cool boundary-layer temperatures. However, effective SRH near 300 m2/s2 will conditionally favor tornadoes with any established supercells that develop late near the MS River. ..Jewell.. 02/14/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1016 AM CST Tue Feb 14 2023 Valid 141630Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON/EVENING FOR EASTERN KS INTO WEST CENTRAL/NORTHWEST MO... ...SUMMARY... A few strong to severe thunderstorms are possible, mainly from eastern Kansas into western Missouri this afternoon and early evening. ...Eastern KS this afternoon to northern IL tonight... In response to upstream amplification of a midlevel trough over the Great Basin, a downstream shortwave trough over western KS/OK this morning will eject northeastward over MO/IA/IL by early tonight. In the wake of morning rain/clouds, surface heating will contribute to steepening of low-level lapse rates across central/eastern KS this afternoon. Residual boundary-layer dewpoints in the mid-upper 40s and surface temperatures in the mid 50s, beneath 500 mb temperatures close to -25 C, will result in MLCAPE of 250-500 J/kg by mid afternoon across eastern KS. The environment will support low-topped thunderstorm development by mid afternoon in a loose arc or small clusters from south central into eastern KS, immediately in advance of the primary midlevel vorticity center, and on the nose of the steeper low-level lapse rates and drying from the southwest. Forecast soundings show sufficient buoyancy and hodograph length/curvature for some threat of low-topped supercells, with attendant threats for a tornado or two, isolated large hail, and damaging outflow gusts through late afternoon/early evening into west central/northwest MO. This scenario will be quite sensitive to the degree of vertical mixing, with small changes in moisture potentially driving outcome possibilities ranging from no severe to SLGT risk. Some form of the afternoon storm cluster may persist into tonight while spreading northeastward from MO into northern IL. Gusty winds will be possible early tonight with lingering, low-topped convection, but very marginal thermodynamic profiles suggest that severe gusts are unlikely. ..Thompson/Lyons.. 02/14/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0149 PM CST Mon Feb 13 2023 Valid 141200Z - 151200Z There is still some uncertainty regarding precipitation amounts tonight across the Trans Pecos which could impact the fire weather threat on Tuesday. Slight modifications may be necessary once this becomes more clear, but no changes are needed at this time. ..Bentley/Flournoy.. 02/13/2023 .PREV DISCUSSION... /ISSUED 1242 AM CST Mon Feb 13 2023/ ...Synopsis... As an upper-level low continues its northeastward progression into the Plains, a deepening surface cyclone across southeastern Colorado and the Oklahoma Panhandle will bring an increase in winds across much of the Central and Southern Plains. In addition, this low will bring precipitation chances to the Plains late Monday into Tuesday. Areas of western Texas may remain mostly dry, with little to no precipitation. Elevated to critical fire weather conditions will be possible by the afternoon as minimum relative humidity around 15-20 percent overlaps with sustained winds at 20-25 mph (locally higher). Within this region, cured grasses will support potential for fire spread. For now, an Elevated delineation has been put into place given uncertainty in Monday night rainfall. A Critical region may need to be added in further updates. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Feb 13 19:52:02 UTC 2023.

No Mesoscale Discussions are in effect as of Mon Feb 13 19:52:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0124 PM CST Mon Feb 13 2023 Valid 132000Z - 141200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears minimal through tonight. No changes were made to the outlook at 20Z. Scattered daytime thunderstorms will remain possible today across AZ and NM as a strong upper trough moves east, and overnight into parts of the southern Plains when a low-level jet increases lift and moisture advection, resulting in weak elevated instability. Very small hail is conceivable tonight in this region given the cold temperature profiles. Elsewhere, shallow convection over western WA and OR will remain possible through early evening north of the midlevel jet/temperature gradient where cold temperatures aloft will contribute to steep lapse rates. Westerly low-level flow and subsequent upslope into the Cascades may also be a focus for lift today. Instability will remain too weak for any severe risk. ..Jewell.. 02/13/2023 .PREV DISCUSSION... /ISSUED 1026 AM CST Mon Feb 13 2023/ ...AZ/NM this afternoon into the southern Plains tonight... A closed midlevel low over southwest AZ this morning will eject east-northeastward to the southern High Plains by Tuesday morning, in response to amplification of an upstream trough over the Pacific Northwest. Moisture is somewhat limited this morning across AZ/NM, but steep lapse rates will support the potential for isolated thunderstorms through the afternoon, some of which could produce gusty outflow winds. Downstream from the ejecting midlevel trough, surface lee cyclogenesis will occur late today into tonight across southeast CO. The lee cyclogenesis will contribute to strengthening southerly flow across the southern Plains and western Gulf basin. However, moisture return into TX will be somewhat limited by a recent frontal intrusion, with boundary-layer dewpoints expected to remain primarily in the mid 50s to lower 60s. MUCAPE will likely be limited to a few hundred J/kg by the modest moisture return, as midlevel lapse rates are reduced by ascent/saturation overnight. Forecast soundings do show some low-end potential for strong surface gusts with a forced convective band overnight from northwest TX into southwest OK, but the weak buoyancy rooted above the surface and slightly stable low-level profiles suggest that downward momentum transfer will be sufficiently muted to forgo the addition of damaging wind probabilities. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1104 AM CST Mon Feb 13 2023 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS MAINLY FROM EASTERN KANSAS INTO WESTERN MISSOURI... ...SUMMARY... A few strong to severe thunderstorms are possible mainly from eastern Kansas into western Missouri Tuesday afternoon into early evening. ...Synopsis and Discussion... An intense shortwave trough will move from the southern and central High Plains Tuesday morning to the mid MS Valley by 00Z, with strong height falls across the region. During this period, a surface low will move from KS into IA, with 50+ kt low-level jet moving from eastern OK/TX across AR, MO, and IL. Instability will be limited due to the early stages of moisture return, with generally sub-50 F dewpoints ahead of the low track. However, cold temperatures aloft combined with daytime heating may result in a few hundred J/kg of SBCAPE from eastern KS into western MO during the afternoon. Otherwise, ongoing precipitation will limited destabilization and heating from the ArkLaTex northward into MN. Given midlevel temperatures near -25 C beneath the upper wave, surface temperatures in the 50s F and 40s F dewpoints may be sufficient for a few low-topped storms to develop after 20Z in an arc across eastern KS and into western MO, coincident with the cooling aloft. Supercell wind profiles may support a brief tornado, hail or damaging gust threat. At this time, it appears limited moisture and instability will mitigate the threat somewhat. Elsewhere, a line of low-topped convection may occur along the front extending southward into eastern OK and TX early in the day, moving into AR and LA by afternoon. Poor lapse rates aloft this far south along with very little MUCAPE should preclude a severe risk, despite strong low-level wind fields. ..Jewell.. 02/13/2023 Read more