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WW 0138 Status Updates
STATUS REPORT ON WW 138 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NW DEQ TO 5 N FSM TO 30 S UMN TO 20 NNE UMN TO 25 NW SGF TO 45 WSW JEF TO 10 NNE COU. ..BENTLEY..04/15/23 ATTN...WFO...LZK...TSA...SGF...LSX... STATUS REPORT FOR WS 138 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC005-009-015-029-033-047-049-051-065-071-083-087-089-097-101- 105-113-115-127-129-131-137-141-143-149-152240- AR . ARKANSAS COUNTIES INCLUDED ARE BAXTER BOONE CARROLL CONWAY CRAWFORD FRANKLIN FULTON GARLAND IZARD JOHNSON LOGAN MADISON MARION MONTGOMERY NEWTON PERRY POLK POPE SCOTT SEARCY SEBASTIAN STONE VAN BUREN WASHINGTON YELL MOC007-009-027-029-043-051-055-059-065-067-071-073-077-091-093- 105-109-125-131-135-139-141-149-151-153-161-167-169-179-203-209- 213-215-219-221-225-229-152240- MO . MISSOURI COUNTIES INCLUDED ARE Read more

WW 138 SEVERE TSTM AR KS MO OK 151750Z - 160000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 138 NWS Storm Prediction Center Norman OK 1250 PM CDT Sat Apr 15 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western to northern Arkansas Far southeast Kansas Southern to central Missouri Far eastern Oklahoma * Effective this Saturday afternoon and evening from 1250 PM until 700 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging winds likely with isolated significant gusts to 75 mph possible A tornado or two possible SUMMARY...Several supercells will develop across the Ozark Plateau region with a primary hazard of very large hail. Upscale growth into a line is expected later this afternoon across central Missouri and northern Arkansas with an increasing damaging wind threat. The severe thunderstorm watch area is approximately along and 70 statute miles east and west of a line from 15 miles north northeast of Jefferson City MO to 35 miles east southeast of Poteau OK. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 137... AVIATION...A few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 23035. ...Grams Read more

MD 0530 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN TEXAS
Mesoscale Discussion 0530 NWS Storm Prediction Center Norman OK 0357 PM CDT Sat Apr 15 2023 Areas affected...Eastern Texas Concerning...Severe potential...Watch possible Valid 152057Z - 152300Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms posing a risk of damaging wind and hail are expected to develop within the next couple of hours. A Severe Thunderstorm watch is being considered. DISCUSSION...Towering cumulus has been developing along an eastward moving cold front in eastern Texas. Ahead of this development, MLCAPE is approaching 3000-4000 J/kg. Effective shear is marginal, around 20-30 kts. Initial development will pose a severe hail risk before mode transitions to become more linear as forcing for ascent increasing with eastward progression of the cold front. This area is being monitored for a potential Severe Thunderstorm Watch. ..Thornton/Grams.. 04/15/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SHV...HGX...FWD...EWX... LAT...LON 31169718 31519684 32369607 32449531 32259482 32109469 31759453 31409461 30979491 30619519 30529547 30339591 30269623 30269654 30319691 30359700 30399702 31169718 Read more

MD 0529 CONCERNING SEVERE THUNDERSTORM WATCH 138... FOR CENTRAL/SOUTHERN MISSOURI INTO PARTS OF NORTHERN/WEST-CENTRAL ARKANSAS
Mesoscale Discussion 0529 NWS Storm Prediction Center Norman OK 0338 PM CDT Sat Apr 15 2023 Areas affected...central/southern Missouri into parts of northern/west-central Arkansas Concerning...Severe Thunderstorm Watch 138... Valid 152038Z - 152245Z The severe weather threat for Severe Thunderstorm Watch 138 continues. SUMMARY...A threat for very large hail will continue across WW 138. An increasing risk for swaths of damaging gusts is expected in the next couple of hours as storms develop into a line as they spread east late this afternoon into early evening. DISCUSSION...A broken line of supercells/clusters are ongoing from central MO into northwest AR this afternoon. These storms have a history of producing mainly 1-2 inch hail, but some as large as 4 inches in diameter have been observed. Moderate instability/steep midlevel lapse rates and elongated hodographs will continue to support storms capable of severe hail for the next few hours. As convection continues shift eastward, storms are expected to congeal and develop upscale into a bow/QLCS. As this occurs, the risk for damaging gusts will increase across eastern portions of the watch area. See MCD 528 for downstream watch potential. ..Leitman.. 04/15/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...LZK...SGF...TSA... LAT...LON 38529256 38809206 38739101 38369089 37269111 35519239 35019310 34739397 34729456 35339449 36929404 37709344 38529256 Read more

WW 0137 Status Updates
STATUS REPORT ON WW 137 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 85 E BVE TO 40 SSE MOB TO 15 E MOB TO 40 WNW GZH. ..BENTLEY..04/15/23 ATTN...WFO...MOB...LIX...JAN... STATUS REPORT FOR WS 137 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ALC003-152140- AL . ALABAMA COUNTIES INCLUDED ARE BALDWIN FLC033-113-152140- FL . FLORIDA COUNTIES INCLUDED ARE ESCAMBIA SANTA ROSA GMZ630-631-634-650-152140- CW . ADJACENT COASTAL WATERS INCLUDED ARE NORTH MOBILE BAY SOUTH MOBILE BAY Read more

WW 137 SEVERE TSTM AL LA MS CW 151620Z - 152100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 137 NWS Storm Prediction Center Norman OK 1120 AM CDT Sat Apr 15 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Far southwest Alabama Southeast Louisiana Southeast Mississippi Coastal Waters * Effective this Saturday morning and afternoon from 1120 AM until 400 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible SUMMARY...A linear MCS should spread east across the central Gulf Coast through late afternoon with a threat for strong to locally severe wind gusts. The severe thunderstorm watch area is approximately along and 55 statute miles north and south of a line from 35 miles west northwest of New Orleans LA to 30 miles southeast of Mobile AL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...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 27035. ...Grams Read more

MD 0528 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR EAST-CENTRAL/SOUTHEAST MISSOURI AND WEST-CENTRAL/SOUTHWEST ILLINOIS
Mesoscale Discussion 0528 NWS Storm Prediction Center Norman OK 0321 PM CDT Sat Apr 15 2023 Areas affected...east-central/southeast Missouri and west-central/southwest Illinois Concerning...Severe potential...Watch likely Valid 152021Z - 152215Z Probability of Watch Issuance...80 percent SUMMARY...Severe potential is expected to increase into late afternoon/early evening from east-central/southeast Missouri into west-central/southwest Illinois. A watch will likely be needed in the next couple hours. DISCUSSION...A broken line of severe supercells continues to develop and shift east/northeast across southwest into central MO and western AR across WW 138. East of the watch, airmass recovery has been slower due to earlier day convection. However, plenty of heating through the afternoon has allowed temperatures to warm into the mid/upper 70s with dewpoints increasing into the low 60s (mid/upper 60s further south toward the MS/OH River confluence/southeast MO vicinity). Combined with steep midlevel lapse rates, MLCAPE values have increased to around 1000-1500 J/kg late this afternoon, with some further destabilization expected. The expectation is that the supercell clusters further west will develop upward into a bow/QLCS as convection approaches the MS River/southeast MO. While some hail potential will continue, this upscale development will support an increasing threat for swaths of damaging gusts. Current KLSX VWP data indicate larger than previously expected low-level hodographs, with forecast guidance also indicating a corridor of greater low-level SRH extending southward along the MS River vicinity through this evening. If backed low-level winds persist, this could indicated some greater potential for mesovortex tornadoes as the line of convection surges eastward this evening. Timing is a bit uncertain as visible satellite indicated some attempts at convective development across central MO ahead of the ongoing supercells. If this activity develops further, a watch may be needed sooner downstream from WW 138. Regardless, a watch is expected across the MCD area in the next couple of hours. ..Leitman/Grams.. 04/15/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...ILX...MEG...LSX... LAT...LON 38999122 39159129 39339121 39419096 39519055 39569019 39328973 38978931 38628908 38028898 37608897 37188896 36848931 36608972 36479024 36589077 36979085 37689071 38479083 38839101 38999122 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sat Apr 15 2023 Valid 152000Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF CENTRAL AND SOUTHERN MISSOURI AND ADJACENT SOUTHWESTERN ILLINOIS...SOUTHWARD TO NORTHERN LOUISIANA... ...SUMMARY... Severe risk will continue this afternoon and tonight -- with greatest potential focused across the Mid-Mississippi/Lower Missouri Valleys. Within the main risk area, very large hail and damaging winds will be the dominant hazards in terms of coverage, but a few tornadoes will be possible. ...Discussion... The ongoing convective/severe-weather event continues to unfold largely as described in prior outlooks, with the most substantial severe risk evolving at this time across far eastern Oklahoma and into southern Missouri and northwestern Arkansas. Here, supercell development is underway, with very large hail being reported. This event will continue to expand in coverage, as the all-hazard risk evolves across this region. Less widespread risk is forecast to expand southwestward over the next several hours, while local/limited risk -- primarily in the form of strong winds -- continues for a couple more hours over the central Gulf Coastal area. Aside from minor line adjustments to account for recent convective evolution, no substantial changes to outlook areas appear necessary with this update. ..Goss.. 04/15/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Apr 15 2023/ ...Mid MS Valley to the Gulf coast... A shortwave trough over the central Great Plains will shift east into the Mid-MS Valley through tonight. This trough has two embedded impulses, one across central KS and the other in eastern CO. The latter is expected to become dominant as the trough and attendant mid-level jet amplify, centered on this evening. The leading impulse will likely aid in initial surface-based thunderstorm development in the Ozark Plateau, immediately ahead of the primary surface cyclone along the northern return of richer boundary-layer moisture from eastern OK/western AR. Activity will expand northeast in MO, as well as develop south along and ahead of an eastward-moving cold front through AR to southeast TX. Weak low-level shear and rather modest hodograph curvature suggests that large hail will be the primary initial threat. Significant severe hail will be possible owing to very steep mid-level lapse rates initially and ample buoyancy amid 30-40 kt effective bulk shear. How quickly storms grow upscale from discrete supercells into a QLCS is somewhat uncertain, but is most likely to occur first across MO/northern AR towards the Mid-MS Valley in the late afternoon to early evening. This will yield a corresponding increase in the damaging wind threat. The 12Z NAM is substantially stronger than the 15Z RAP and 00Z ECMWF with the degree of low-level mass response ahead of the line in the early evening, lowering confidence in the degree of embedded tornado threat. The northern line of storms will weaken into tonight as storms spread east of the Mid-MS Valley amid diminishing buoyancy with eastern extent. Farther south, a messier mix of semi-discrete supercells and clusters might evolve into a southeast-moving QLCS spreading across the Lower MS Valley tonight. Low confidence exists in this scenario given potential for multiple rounds of convection this afternoon and evening. An ongoing MCS across LA/far southern MS may continue east along the central Gulf Coast with a primary threat of strong to isolated severe gusts. The track of this MCS this morning has yielded a swath of convective overturning in its wake, suggesting that weak low-level warm theta-e advection along/atop its residual outflow could support redevelopment of scattered storms around peak heating. Deep-layer vertical shear will be weaker with southern extent, but steep lapse rates and large undisturbed warm-sector CAPE will support potential for large hail/damaging winds late this afternoon/evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sat Apr 15 2023 Valid 161200Z - 171200Z ...NO CRITICAL AREAS... ...Portions of the central Plains... In the wake of departing cold front, strong northwest winds are expected through much of D2/Sunday from NE/KS into portions of northeastern OK. Model soundings show some diurnal heating and drying will favor lower afternoon RH of 20-30%. However, recent precipitation in the last 48 hours has resulted in widespread wetting rainfall of at least 0.1-0.25 inches over much of the eastern Plains. It remains unclear how receptive short-hour fuels are to fire spread given the recent rain and higher overnight humidity recoveries. Despite the fuels, the magnitude of strong gusts in the 25-40 mph range may still support some locally elevated to near-critical fire-weather conditions D2/Sunday afternoon. Confidence remains too low to introduce an Elevated area given questions on fuels and marginal RH values. See the previous discussion for more information. ..Lyons.. 04/15/2023 .PREV DISCUSSION... /ISSUED 0110 AM CDT Sat Apr 15 2023/ ...Synopsis... Surface high pressure and associated cooler temperatures will overspread the southern Plains as a mid-level ridge gradually builds overhead. Overall dry conditions should prevail across the southern High Plains. However, the lack of widespread overlapping dry and windy conditions in the latest guidance limits confidence for introducing fire weather highlights this outlook. A better chance for overlapping dry and windy conditions may occur across portions of the central Plains, with 20+ mph sustained northwesterly surface winds overlapping 20-30 percent RH by afternoon peak heating. However, fire weather highlights have been withheld since some guidance members suggest RH will be too high to support a significant wildfire-spread threat. In addition, portions of the east-central Plains are currently experiencing heavy rain due to scattered to widespread thunderstorms, making it difficult to pinpoint where dry and windy conditions will overlap with receptive fuels. ...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 1228 PM CDT Sat Apr 15 2023 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE GREAT LAKES TO THE CAROLINAS...AND ACROSS PORTIONS OF FLORIDA... ...SUMMARY... Marginally severe thunderstorms, associated with isolated damaging winds and hail will be possible in parts of the Southeast and Carolinas, northward into the Appalachians and southern Great Lakes ...Synopsis... An upper low progged to lie over the eastern Iowa/northeastern Missouri/western Illinois vicinity at the start of the period, will shift east-northeastward toward Lake Michigan, while deepening through the period. Broad cyclonic flow surrounding the low will spread across much of the eastern third of the country, as broad mid-level height falls encompass nearly all of the eastern U.S. west and south of New England. In conjunction with the upper low's advance, a cold front will shift eastward across the eastern half of the country, reaching/cresting the Appalachians by early evening and then clearing the middle and southern Atlantic coastal region overnight. Elsewhere, an upper low over the northeastern Pacific will advance southeastward toward western Canada and the Pacific Northwest, with ridging sandwiched between the two upper lows to shift slowly eastward across the Intermountain West through the period. ...Portions of the Great Lakes region southeastward to the Carolinas... In the wake of diminishing/dissipating Day 1 convection across the mid Ohio and Tennessee Valleys, early-day convective redevelopment is expected along the advancing cold front. Initial redevelopment should occur nearer the upper low -- i.e. across lower Michigan and parts of the Midwest -- where somewhat steeper lapse rates aloft will reside. Eventually, with the aid of daytime heating/destabilization, storms should expand southward along the front into the southern Appalachians. While CAPE should remain limited overall -- in part due to prior-day convection and lingering cloud cover, strong flow aloft surrounding the upper low suggests some potential for organized storms/storm clusters, along with attendant/local potential for a few strong to severe wind gusts. Greatest potential may evolve across the Ohio vicinity during the afternoon, but questions regarding degree/coverage of wind potential preclude upgrade to slight risk at this time. Convection should spread into the central Appalachians during the evening, where some risk for a couple of strong gusts may linger. Meanwhile, there is some potential that ongoing convection early in the period may be crossing the Carolinas, which also could be accompanied by the risk for a strong gust or two, before moving offshore. ...Parts of central and southern Florida... Continued passage of weak disturbances aloft embedded in the southern-stream westerlies will result in weak height falls across Florida. This is reflected at the surface as development of weak troughing across central Florida per 12Z NAM guidance. Despite weak lapse rates aloft, daytime heating/destabilization should support scattered to isolated, afternoon storm development, which is depicted in several CAM runs across central and parts of southern Florida. With the southern fringe of the stronger mid-level westerlies aloft extending southward across central Florida, a strong to severe wind gust or two will be possible through early evening when convection should be weakening and moving offshore. ..Goss.. 04/15/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1134 AM CDT Sat Apr 15 2023 Valid 151700Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEW MEXICO... The previous outlook remains valid with only minimal changes for the most recent guidance. Cold frontal position has moved slightly farther south than expected across portions of the TX Panhandle. The Elevated area was trimmed slightly to account for lower fire-weather probabilities. Otherwise, see the previous discussion. ..Lyons.. 04/15/2023 .PREV DISCUSSION... /ISSUED 1250 AM CDT Sat Apr 15 2023/ ...Synopsis... A surface low will drift across the southern Plains toward the central Mississippi Valley as a mid-level trough overspreads the central U.S. today. Deep-layer westerly flow is expected across the southern High Plains during the afternoon hours, supporting dry downslope flow from the southern Rockies in central New Mexico southeastward into western and southern Texas, including areas along the Rio Grande. Elevated highlights are in place for areas that should experience at least periodic bouts of 15 mph sustained northwesterly surface winds amid 15 percent RH. Critical highlights have also been maintained for portions of central into eastern New Mexico, where guidance consensus depicts 20 mph sustained northwesterly surface winds overlapping with 10 percent RH for at least a few hours around afternoon peak heating. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1130 AM CDT Sat Apr 15 2023 Valid 151630Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID-MS VALLEY TO NORTHERN LA... ...SUMMARY... Scattered swaths of severe thunderstorms are expected through tonight from the Mid-Missouri Valley to the Gulf Coast. Large hail and damaging winds will be the dominant hazards in terms of coverage, but a few tornadoes will be possible, especially across parts of Missouri and Arkansas. ...Mid MS Valley to the Gulf coast... A shortwave trough over the central Great Plains will shift east into the Mid-MS Valley through tonight. This trough has two embedded impulses, one across central KS and the other in eastern CO. The latter is expected to become dominant as the trough and attendant mid-level jet amplify, centered on this evening. The leading impulse will likely aid in initial surface-based thunderstorm development in the Ozark Plateau, immediately ahead of the primary surface cyclone along the northern return of richer boundary-layer moisture from eastern OK/western AR. Activity will expand northeast in MO, as well as develop south along and ahead of an eastward-moving cold front through AR to southeast TX. Weak low-level shear and rather modest hodograph curvature suggests that large hail will be the primary initial threat. Significant severe hail will be possible owing to very steep mid-level lapse rates initially and ample buoyancy amid 30-40 kt effective bulk shear. How quickly storms grow upscale from discrete supercells into a QLCS is somewhat uncertain, but is most likely to occur first across MO/northern AR towards the Mid-MS Valley in the late afternoon to early evening. This will yield a corresponding increase in the damaging wind threat. The 12Z NAM is substantially stronger than the 15Z RAP and 00Z ECMWF with the degree of low-level mass response ahead of the line in the early evening, lowering confidence in the degree of embedded tornado threat. The northern line of storms will weaken into tonight as storms spread east of the Mid-MS Valley amid diminishing buoyancy with eastern extent. Farther south, a messier mix of semi-discrete supercells and clusters might evolve into a southeast-moving QLCS spreading across the Lower MS Valley tonight. Low confidence exists in this scenario given potential for multiple rounds of convection this afternoon and evening. An ongoing MCS across LA/far southern MS may continue east along the central Gulf Coast with a primary threat of strong to isolated severe gusts. The track of this MCS this morning has yielded a swath of convective overturning in its wake, suggesting that weak low-level warm theta-e advection along/atop its residual outflow could support redevelopment of scattered storms around peak heating. Deep-layer vertical shear will be weaker with southern extent, but steep lapse rates and large undisturbed warm-sector CAPE will support potential for large hail/damaging winds late this afternoon/evening. ..Grams/Thornton.. 04/15/2023 Read more

No watches are valid as of Fri Apr 14 21:29:02 UTC 2023.

MD 0515 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR NORTH CENTRAL OKLAHOMA...EASTERN KANSAS...FAR SOUTHEASTERN NEBRASKA...AND FAR SOUTHWESTERN IOWA
Mesoscale Discussion 0515 NWS Storm Prediction Center Norman OK 0347 PM CDT Fri Apr 14 2023 Areas affected...North central Oklahoma...eastern Kansas...far southeastern Nebraska...and far southwestern Iowa Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 142047Z - 142145Z Probability of Watch Issuance...80 percent SUMMARY...Threat of damaging winds and large hail increasing through the afternoon and evening. Severe Thunderstorm Watch needed within the next hour or two. DISCUSSION...Moisture advection has been ongoing across much of the Central Plains this afternoon, with mid 50s dew points extending into southern Kansas as of 20z. Visible satellite has shown a deepening cumulus field across the Oklahoma/Kansas border near the dry line within the last couple of hours. Surface objective analysis indicates steady destabilization has been occurring beneath a mid-level capping inversion across much of the Central/Southern Plains. As the trough ejects eastward and further eastward mixing of the dry line occurs this evening, inhibition is expected to weaken with development of thunderstorms expected by 22-00z along the dry line and cold front. Mode is expected to be semi-discrete initially, with a transition to mixed mode/linear expected as shear profiles favor motion parallel to the dry line with tendency for upscale growth. RAP forecast soundings indicate convection will be largely high-based given high LCLs, with the risk of damaging winds and large hail. A Severe Thunderstorm Watch will likely be needed within the hour or two. ..Thornton/Leitman.. 04/14/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...EAX...TSA...OAX...TOP...ICT...OUN...GID... DDC... LAT...LON 36599862 37399871 38919830 39389831 39879804 40109758 40289714 40519684 40559664 40869616 40779483 39889458 39199471 38499507 37899540 36949620 36689684 36269740 36139775 36599862 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Fri Apr 14 2023 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHEASTERN NEBRASKA VICINITY SOUTHWARD TO NORTHERN OKLAHOMA... ...SUMMARY... Severe thunderstorms capable of producing large hail and damaging winds are most likely from late afternoon through evening from southeast Nebraska into central Kansas and northwest Oklahoma. Additional isolated severe thunderstorms are possible across south-central Texas through evening, and across parts of the Carolinas and southeast Virginia the remainder of this afternoon. ...Discussion... Aside from minor adjustments to outlook lines in a few areas -- primarily to reflect ongoing convective evolution -- no substantive changes appear necessary at this time. Convection is forecast to increase across the Plains region over the few hours, while a storm or two may also develop across portions of the Hill Country and South Texas, as described in prior outlooks. ..Goss.. 04/14/2023 .PREV DISCUSSION... /ISSUED 1124 AM CDT Fri Apr 14 2023/ ...Central Plains Vicinity... At midday, a surface low was located near the central KS/NE border. A dryline extended south from the low across western KS into far west TX, while a cold front arced across southeast CO. The dryline is forecast to mix eastward to western OK and central TX by late afternoon, while the cold front sags south/southeast toward the OK/TX Panhandle and central KS. The northern extent of the cold front will shift east from southeast NE into central MN through evening. Ahead of these surface boundaries, modest moisture return is underway on strengthening southerly low-level flow. Upper 50s to near 60 F dewpoints are expected as far north as far southeast NE this evening. As the western upper trough begins to eject eastward this evening, large-scale ascent coupled with frontal convergence should provide support for thunderstorm development. Steep midlevel lapse rates (8-9 C/km) and modest boundary-layer moisture will support moderate to strong destabilization with MLCAPE values greater than 2000 J/kg forecast along/west of the I-35 corridor. While deep-layer south to southwesterly flow will remain modest through 500 mb (generally 25-35 kt), effective shear magnitudes around 30-35 kt will marginally favor initial high-based supercells. With time, upward development into clusters/bows is possible during the evening. Large hail (some greater than 2 inches) and damaging gusts (some to around 75 mph) are expected across the Slight risk (Level 2 of 5) area from southeast NE into northwest OK. Additional strong storms capable of gusty winds and hail will be possible in the post-frontal upslope regime across southeast CO into western KS just behind the southward-sagging cold front. High based convection with well-mixed sub-cloud profiles may support mostly dry downburst winds. Steep lapse rates and modest shear also could support large hail in any cells that can persist/remain organized. A more conditional threat may extent southward toward the I-40 corridor in western/west-central OK. Concerns over stronger capping with southward extent will preclude expansion of severe probabilities across OK. However, a strong/severe cell could develop near the dryline within the Marginal risk (Level 1 of 5) area as far south as I-40 in western OK. ...Edwards Plateau Vicinity in TX... Latest forecast guidance has been more aggressive in eroding midlevel capping across south/south-central TX this afternoon/evening. Deep boundary-layer moisture is forecast across south TX amid steep midlevel lapse rates, supporting strong destabilization this afternoon. Elongated forecast hodographs and supercell wind profiles suggest large hail (some potentially greater than 2 inches) will be possible if cells develop. Some potential exists for developing convection to form a bow tracking east toward the Middle TX Coast during the evening/early overnight period. If this occurs, some risk for locally damaging gusts also will exist. A Marginal risk (Level 1 of 5) has been included, and an upgrade to Slight risk (Level 2 of 5) may be needed in subsequent outlooks if trends continue to increase. ...Carolinas/southern VA this afternoon/evening... The closed midlevel low over the TN Valley will gradually evolve into an open wave while ejecting northeastward toward the Mid-Atlantic tonight. Surface dewpoints in the mid/upper 60s are in place across the Carolinas and will continue to spread northward toward southern VA. Surface heating amid cloud breaks is supporting weak destabilization early this afternoon. Midlevel lapse rates and vertical shear will remain modest (< 7 C/km and near 30 kt effective bulk shear), but MLCAPE approaching 1000 J/kg will support scattered storm cells/clusters. Isolated wind damage and marginally severe hail will be possible for a few hours this afternoon into early evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0208 PM CDT Fri Apr 14 2023 Valid 151200Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF CENTRAL AND EASTERN NEW MEXICO... ...Central and Eastern New Mexico... Confidence has increased such that widespread Critical fire-weather conditions are possible with strong northwest flow across portions of central and eastern New Mexico D2/Saturday. Area forecast soundings show very low humidity (5-12%) overlapping with at least a few hours of frequent wind gusts near 25 mph. Continued drying of area fuels with ERC values in the 80th+ percentile, critical fire-weather conditions are possible. See the previous discussion for additional information. ..Lyons.. 04/14/2023 .PREV DISCUSSION... /ISSUED 0211 AM CDT Fri Apr 14 2023/ ...Synopsis... A mid-level trough will overspread the central Plains and impinge on the MS Valley today, resulting in a surface low drifting toward the Great Lakes and a cold front sweeping across the southern Plains. Downslope flow along the lee of the southern Rockies will encourage widespread 15 mph sustained northwesterly surface winds and 15 percent RH from eastern NM into western TX, warranting Elevated highlights. At least locally Critical conditions are also possible in central into eastern New Mexico, and Critical highlights may be warranted in future outlooks pending guidance consistency. ...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 1245 PM CDT Fri Apr 14 2023 Valid 151200Z - 161200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL MISSOURI SOUTHWARD TO NORTHERN LOUISIANA... ...SUMMARY... Severe thunderstorms -- capable of producing large to very large hail and damaging wind gusts, as well as a couple of tornadoes -- are possible from Missouri and the Mid-Mississippi Valley, southward to the Lower Mississippi and Sabine Valleys. ...Synopsis... As a weakening upper low over the Mid-Atlantic region shifts northeastward, a larger trough exiting the Rockies is forecast to move steadily eastward across the Plains, gradually acquiring negative tilt as it advances. At the surface, a cold front associated with the western U.S. upper trough should lie initially from the western Upper Great Lakes region southwestward into the southern Plains. The boundary is forecast to advance eastward with time, with cyclogenesis forecast to occur along the baroclinic zone across the Mid-Mississippi Valley area during the second half of the period. As the low moves northward toward Lake Michigan overnight, the trailing portion of the cold front is progged to surge southeastward across Missouri/Arkansas/Louisiana through the evening. By Saturday morning, the front should extend from the Lower Ohio and Tennessee Valleys to the central Gulf Coast states. ...Missouri and the Mid-Mississippi Valley south to the Sabine and lower Mississippi Valleys... A complex convective evolution is apparent for Friday across a region centered near/just west of the middle and lower Mississippi Valleys. This will be in part due to a series of perturbations in the southern-stream flow field that are progged to be moving out of Texas, across the western Gulf of Mexico and Lower Mississippi Valley into the central Gulf Coast states through the first half of the period. Lingering convection associated with these perturbations may be ongoing at the start of the period across portions of eastern Texas and Louisiana into southern Arkansas, though CAM guidance differs on the exact location -- and degree -- of convective coverage early. Despite these differences, CAMs generally depict a midday increase in storms across the Lower Mississippi Valley to the central Gulf Coastal region, which seems reasonable as daytime heating helps boost surface-based CAPE, owing in part to steep mid-level lapse rates. Deep-layer shear is progged to decrease with southward extent, hence the gradient in probability lines across Louisiana. However, potential for large hail and damaging winds -- and possibly a tornado -- should evolve across this area. Uncertainty precludes substantial changes to the existing outlook across the area. Adjustments in later outlooks may be needed, once Day 1 convective development across Texas -- associated with the aforementioned southern-stream energy -- becomes more clear. Farther north, as the upper system advances, the combination of very steep lapse rates aloft, and diurnal heating of a seasonably moist boundary layer (low 60s dewpoints into northern Missouri, to near 70 into the southern Arkansas/Louisiana area) will occur. This will result in a strongly unstable environment (2000 to 3000 J/kg mixed-layer CAPE). Storm development is expected to occur by mid afternoon, near and just ahead of the advancing cold front, from western and central Missouri southward into Arkansas. Aided by roughly 30 kt south-southwesterlies at low levels veering weakly and increasing to 35 to 45 kt from the southwest at mid levels, shear will favor supercells -- which will quickly become capable of producing very large hail in excess of tennis ball to baseball size. While low-level shear is not progged to be excessive, a couple of these supercells may become capable of producing tornadoes. With time, convective development both northward and southward along the front is expected. Upscale growth into an at least loosely-organized band or line is anticipated, extending from southeastern Iowa/western Illinois south-southwestward along the advancing front into the Sabine River Valley area. As a result of this anticipated evolution, have expanded higher all-hazard probabilities northward in this outlook, into much of Missouri. Along with continued risk for hail, damaging wind potential should increase during the evening -- particularly across the Missouri/Arkansas area. Storms should diminish in intensity later in the evening, as they cross the Mid-Mississippi Valley, but farther south, may remain severe across Louisiana and into Mississippi through the evening and possibly into the overnight hours. ..Goss.. 04/14/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1145 AM CDT Fri Apr 14 2023 Valid 141700Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN HIGH PLAINS...INTO WEST TEXAS.... The previous outlook remains valid with minor adjustments. The Critical Area was expanded southward across portions of southwestern TX where greater confidence in widespread critical fire-weather conditions is expected this afternoon. The Dry Thunderstorm area has also been shifted southwest into portions of the northern TX Panhandle where a risk for dry lightning strikes is possible with high-based storms. Otherwise the previous forecast remains valid with minimal changes. Locally elevated fire-weather conditions are possible across the upper Midwest and portions of the Northeast. See the prior discussion for more information. ..Lyons.. 04/14/2023 .PREV DISCUSSION... /ISSUED 0141 AM CDT Fri Apr 14 2023/ ...Synopsis... A surface low will deepen across the central Plains as a mid-level trough overspreads the central U.S. today. A surface dryline will trail the surface low across southwestern KS into western TX and drift eastward through the afternoon. Widespread 20+ mph sustained westerly surface winds coinciding with 10 percent RH will support Critical fire weather conditions across portions of the southern High Plains (especially eastern NM into western TX) given dry grasses amid green-up. A threat for fire starts also exists with any storms that initiate along the dryline across northwest OK into southwest KS. Here, storms will be initially high-based given limited low-level moisture. These storms will quickly pass over dry grasses with minimal rainfall, amid breezy ambient conditions, which may exacerbate any grass fires started by lightning. Elevated highlights were also added over portions of the Upper Mississippi Valley. Here, 10-15 mph southerly surface winds may coincide with 25 percent RH by afternoon peak heating ahead of an advancing surface lee trough. The presence of dormant brush and lack of recent rainfall suggest fuels should be at least modestly receptive to wildfire spread, warranting the introduction of fire weather highlights. Dry conditions are also expected across portions of the Mid Atlantic during the afternoon. However, the lack of a stronger surface wind field precludes fire weather highlights, with wildfire-spread potential expected to remain more localized. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0135 Status Updates
STATUS REPORT ON WW 135 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..KERR..04/13/23 ATTN...WFO...MLB...JAX... STATUS REPORT FOR WS 135 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC009-019-031-035-069-089-095-107-109-117-127-132140- FL . FLORIDA COUNTIES INCLUDED ARE BREVARD CLAY DUVAL FLAGLER LAKE NASSAU ORANGE PUTNAM ST. JOHNS SEMINOLE VOLUSIA AMZ452-454-550-552-132140- CW . ADJACENT COASTAL WATERS INCLUDED ARE COASTAL WATERS FROM FERNANDINA BEACH TO ST. AUGUSTINE FL OUT 20 NM COASTAL WATERS FROM ST. AUGUSTINE TO FLAGLER BEACH FL OUT 20 NM FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM Read more

WW 135 SEVERE TSTM FL CW 131830Z - 140200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 135 NWS Storm Prediction Center Norman OK 230 PM EDT Thu Apr 13 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northeastern Florida Coastal Waters * Effective this Thursday afternoon and evening from 230 PM until 1000 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Scattered large hail events to 1.5 inches in diameter possible SUMMARY...Scattered thunderstorms are expected to increase in intensity this afternoon as they track eastward toward the coast. Damaging gusts and isolated large hail will be the main hazards with these storms through early evening. The severe thunderstorm watch area is approximately along and 80 statute miles north and south of a line from 55 miles west southwest of St Augustine FL to 30 miles east northeast of Daytona Beach FL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for 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. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 134... AVIATION...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 24035. ...Leitman Read more