Severe Storms

WW 0040 Status Updates
STATUS REPORT ON WW 32 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 E 7R4 TO 60 NNW PIB TO 30 SSW GWO. ..SMITH..02/09/23 ATTN...WFO...LCH...LIX...JAN... STATUS REPORT FOR WT 32 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC005-007-063-091-093-095-101-103-105-117-090440- LA . LOUISIANA PARISHES INCLUDED ARE ASCENSION ASSUMPTION LIVINGSTON ST. HELENA ST. JAMES ST. JOHN THE BAPTIST ST. MARY ST. TAMMANY TANGIPAHOA WASHINGTON MSC007-015-031-035-043-051-061-065-067-073-077-079-083-089-091- 097-099-101-109-113-121-123-127-129-147-163-090440- MS . MISSISSIPPI COUNTIES INCLUDED ARE ATTALA CARROLL COVINGTON FORREST GRENADA HOLMES JASPER JEFFERSON DAVIS JONES LAMAR LAWRENCE LEAKE LEFLORE MADISON MARION MONTGOMERY NESHOBA NEWTON PEARL RIVER PIKE RANKIN SCOTT SIMPSON SMITH Read more

WW 40 TORNADO AL MS 161950Z - 170200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 40 NWS Storm Prediction Center Norman OK 150 PM CST Thu Feb 16 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and southwest Alabama Extreme southeast Mississippi * Effective this Thursday afternoon and evening from 150 PM until 800 PM CST. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...Scattered supercells will spread northeastward from Mississippi into Alabama through the remainder of the afternoon/evening, and additional storm development will be possible into central/southwest Alabama. The storm environment will favor a threat for tornadoes, a couple of which could be strong, along with damaging gusts of 60-70 mph and isolated large hail near 1 inch in diameter. The tornado watch area is approximately along and 60 statute miles east and west of a line from 55 miles north northwest of Birmingham AL to 75 miles south southeast of Meridian MS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 38...WW 39... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24035. ...Thompson Read more

WW 0039 Status Updates
STATUS REPORT ON WW 39 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SSW UOX TO 40 S MKL TO 50 SW CKV TO 10 ENE CKV. ..GOSS..02/16/23 ATTN...WFO...HUN...LMK...MEG...OHX... STATUS REPORT FOR WT 39 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC033-059-077-079-083-089-103-162040- AL . ALABAMA COUNTIES INCLUDED ARE COLBERT FRANKLIN LAUDERDALE LAWRENCE LIMESTONE MADISON MORGAN KYC003-009-053-057-141-169-171-213-227-162040- KY . KENTUCKY COUNTIES INCLUDED ARE ALLEN BARREN CLINTON CUMBERLAND LOGAN METCALFE MONROE SIMPSON WARREN MSC003-009-013-017-057-071-081-095-115-117-139-141-145-161- 162040- MS . MISSISSIPPI COUNTIES INCLUDED ARE Read more

WW 39 TORNADO AL KY MS TN 161800Z - 170100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 39 NWS Storm Prediction Center Norman OK 1200 PM CST Thu Feb 16 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northern Alabama South central Kentucky Northern Mississippi Western and middle Tennessee * Effective this Thursday afternoon and evening from NOON until 700 PM CST. * Primary threats include... A few tornadoes and a couple intense tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...Scattered strong-severe storms will spread eastward across northern Mississippi/western and middle Tennessee into northern Alabama and south central Kentucky through the afternoon. The storm environment will support a threat of both supercells and bowing segments capable of producing damaging winds and a few tornadoes, one or two of which could be strong. The tornado watch area is approximately along and 85 statute miles east and west of a line from 45 miles north northeast of Nashville TN to 30 miles south of Oxford MS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 38... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 25040. ...Thompson Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0133 PM CST Thu Feb 16 2023 Valid 162000Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF MISSISSIPPI AND ALABAMA...AND MIDDLE TENNESSEE... ...SUMMARY... Widely scattered severe thunderstorms are likely from the central Gulf Coast states northward into the Ohio Valley. Isolated strong tornadoes are most likely over Mississippi, Alabama and middle Tennessee. Changes at 20Z include accounting for the cold front position, and reducing severe coverage across far northern areas such as western NY where temperatures will remain cool/stable boundary layer. In addition, severe wind probabilities were deceased to account for a mostly supercell storm mode. Otherwise, supercells remain possible with a threat of tornadoes across the MS/AL/TN portion of the warm sector where dewpoints continues to rise and effective SRH exceeds 200 m2/s2. 18Z soundings from the area indicate plentiful moisture but some disorganization in the wind profile between 850 and 700 mb (veer/back with height). However, scattered storms may continue to grow in coverage, with mesoscale factors resulting in locally favorable corridors later today. Large hail and damaging gusts will also be possible with the strongest storms. For more information see mesoscale discussion 165. ..Jewell.. 02/16/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Thu Feb 16 2023/ ...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. Read more

WW 0038 Status Updates
STATUS REPORT ON WW 38 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 W HEZ TO 30 NNE HEZ TO 65 SSE GLH TO 15 SSW GWO TO 15 NNE GWO TO 20 NNE GWO. ..LYONS..02/16/23 ATTN...WFO...JAN...LIX... STATUS REPORT FOR WT 38 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC029-162040- LA . LOUISIANA PARISHES INCLUDED ARE CONCORDIA MSC001-005-007-015-019-021-023-025-029-031-035-037-043-049-051- 061-063-065-067-069-073-075-077-079-085-087-089-091-097-099-101- 103-105-113-121-123-127-129-147-149-155-157-159-163-162040- MS . MISSISSIPPI COUNTIES INCLUDED ARE ADAMS AMITE ATTALA CARROLL CHOCTAW CLAIBORNE CLARKE CLAY COPIAH COVINGTON FORREST FRANKLIN GRENADA HINDS HOLMES JASPER JEFFERSON JEFFERSON DAVIS JONES KEMPER LAMAR LAUDERDALE LAWRENCE LEAKE LINCOLN LOWNDES MADISON Read more

WW 38 TORNADO LA MS 161555Z - 162300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 38 NWS Storm Prediction Center Norman OK 955 AM CST Thu Feb 16 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Extreme northeast Louisiana Central and southern Mississippi * Effective this Thursday morning and afternoon from 955 AM until 500 PM CST. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Scattered damaging wind gusts to 70 mph likely Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Scattered supercells are expected to spread northeastward into central Mississippi through the afternoon, with the threat for a strong tornado or two, damaging gusts of 60-70 mph, and isolated large hail up to 1.5 inches in diameter. The tornado watch area is approximately along and 70 statute miles east and west of a line from 15 miles south southwest of Mc Comb MS to 35 miles east northeast of Greenwood MS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). 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. && OTHER WATCH INFORMATION...CONTINUE...WW 37... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 23035. ...Thompson Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1248 PM CST Thu Feb 16 2023 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... No updates have been made to the outlook. Elevated fire weather conditions are not expected across the CONUS on Friday. ..Flournoy/Bentley.. 02/16/2023 .PREV DISCUSSION... /ISSUED 1259 AM CST Thu Feb 16 2023/ ...Synopsis... Fire weather concerns across the CONUS will be mitigated by lighter winds, recent precipitation, and cooler temperatures. Fuel moisture is largely above seasonal normals, expect within portions of western and south-central Texas, where less rainfall has allowed drying of fuels. Within this region, lighter winds under building high pressure will help keep the fire weather risk low. ...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 1101 AM CST Thu Feb 16 2023 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States on Friday. ...Synopsis and Discussion... On Friday, a large positive-tilt upper trough will move eastward across the eastern CONUS, with an upper ridge over the Four Corners states. Meanwhile, an upper low will drift south off the CA Coast. At the surface, low pressure will begin the day over NY, with a cold front extending south across the Piedmont and into the northeast Gulf of Mexico. This front will push rapidly eastward through the early afternoon, with dewpoints in the 50s F over the Mid Atlantic rising to the mid 60s F over northern FL. Low-level lapse rates will remain poor ahead of the front over most of the eastern seaboard, the exception being FL. Little if any surface-based instability is forecast to develop, and rapidly veering winds aloft will result in drying. Shear will be very strong near the front, and gusty winds may occur with the expected band of frontal precipitation and wind shift. But the lack of instability or heating will preclude any severe chances prior to the front moving offshore. Just a few lightning flashes will be possible from the FL Panhandle into eastern NC during the day, and perhaps briefly with weak elevated instability from NY into southern New England. ..Jewell.. 02/16/2023 Read more

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