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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

WW 0134 Status Updates
STATUS REPORT ON WW 134 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 S SSI TO 20 SW CSG. ..KERR..04/13/23 ATTN...WFO...JAX...TAE...FFC... STATUS REPORT FOR WT 134 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS GAC001-005-023-025-039-053-069-079-081-091-093-127-145-153-161- 193-197-215-225-229-235-249-259-261-263-269-271-305-307-309-315- 132140- GA . GEORGIA COUNTIES INCLUDED ARE APPLING BACON BLECKLEY BRANTLEY CAMDEN CHATTAHOOCHEE COFFEE CRAWFORD CRISP DODGE DOOLY GLYNN HARRIS HOUSTON JEFF DAVIS MACON MARION MUSCOGEE PEACH PIERCE PULASKI SCHLEY STEWART SUMTER TALBOT TAYLOR TELFAIR WAYNE WEBSTER WHEELER WILCOX THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 134 TORNADO GA 131640Z - 132300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 134 NWS Storm Prediction Center Norman OK 1240 PM EDT Thu Apr 13 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southern Georgia * Effective this Thursday afternoon and evening from 1240 PM until 700 PM EDT. * Primary threats include... A few tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Thunderstorms coverage and intensity will gradually increase through the afternoon. Severe thunderstorms capable of producing scattered damaging gusts, a few tornadoes and isolated large hail will be possible into early evening. The tornado watch area is approximately along and 55 statute miles north and south of a line from 20 miles southwest of Columbus GA to 30 miles north northeast of Jacksonville FL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 133... 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 24035. ...Leitman Read more

MD 0510 CONCERNING TORNADO WATCH 134... FOR CENTRAL GEORGIA
Mesoscale Discussion 0510 NWS Storm Prediction Center Norman OK 0320 PM CDT Thu Apr 13 2023 Areas affected...central Georgia Concerning...Tornado Watch 134... Valid 132020Z - 132215Z The severe weather threat for Tornado Watch 134 continues. SUMMARY...At least low potential for convection capable of producing tornadoes will persist along a slowly northward advancing warm front zonal into early evening. A new Tornado Watch will probably be needed. DISCUSSION...A gradual northward and northeastward progression of a pair of narrow convective bands, and a focusing warm frontal zone for occasional thunderstorm intensification, continues into much of central Georgia. Although a substantial increase in the risk for tornadoes, beyond what has existed the past several hours, still appears unlikely, at least some risk probably will continue into early evening, before subsiding as the boundary-layer near the front stabilizes with nocturnal cooling. ..Kerr.. 04/13/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CHS...CAE...JAX...FFC... LAT...LON 33318518 33068443 32918368 33028245 32958180 32468126 31608210 32078301 32048391 32358480 32838514 33318518 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Apr 13 2023 Valid 132000Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN ALABAMA...SOUTHERN AND WESTERN GEORGIA...AND NORTHERN AND EASTERN FLORIDA... ...SUMMARY... A few tornadoes, along with damaging gusts and isolated large hail, will continue this afternoon and into this evening across parts of the Southeast. A severe gust or two may also occur this afternoon over the central High Plains. ...Discussion... Along with line adjustments to account for recent convective evolution, the enhanced risk/10% tornado outlook area is being removed, as convection nears northern and eastern fringes of the existing risk area. Otherwise, isolated but all-hazard severe risk will continue over the next few hours across the southeastern U.S. area, with risk tapering/moving offshore during the early evening. An isolated/late afternoon or early evening wind gust or two near or exceeding severe levels may also occur, as widely scattered convection develops across the High Plains. ..Goss.. 04/13/2023 .PREV DISCUSSION... /ISSUED 1104 AM CDT Thu Apr 13 2023/ ...Southeast... An upper low over the Lower MS Valley will slowly drift east/northeast through the period. This will maintain southeasterly low-level flow across much of FL/GA and vicinity. A dry slot wrapping around the mid/upper low noted over the northern Gulf and nosing into the FL Panhandle/southern GA late this morning is expected to continue spreading northward through the day. Forecast guidance varies considerably with regard to midlevel moisture and amount of low/midlevel mixing across parts of AL/GA. Given current water vapor imagery, it appears drying across AL seems reasonable with more uncertainty with eastward extent across GA. Further east, southeasterly flow should maintain better boundary-layer moisture compared to further west. Surface dewpoints across northern FL are noted in the mid 60s to near 70 F as of 15z, and surface dewpoints have increased around 4 F over the past 3 hours across southern GA. Continual warm/moist advection into southern GA should result in a zone of quality boundary-layer moisture amid modest vertical shear in the vicinity of a quasi-warm front/confluence zone across southern GA. This area may see greater potential for a few tornadoes through this afternoon. Additionally, supercell wind profiles combined with steep low-level lapse rates amid pockets of stronger heating also will support damaging gusts from parts of AL/GA southward along the eastern coast of FL. Isolated large hail also will be possible with cellular convection across parts of AL/GA, and along the northeast/east-central FL coast. ...High Plains... Isolated to widely scattered thunderstorms are expected to develop this afternoon near the lee trough, in a zone of favorable heating and low-level convergence. Modest boundary-layer moisture (surface dewpoints in the 40s F) with steep low/middle-level lapse rates will support modest destabilization. The main concern will be locally strong to severe downdrafts accelerating through the well-mixed subcloud layer. Low-level stabilization should reduce the convective/severe potential with time during early evening. Read more

MD 0509 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN FLORIDA ATLANTIC COASTAL AREAS
Mesoscale Discussion 0509 NWS Storm Prediction Center Norman OK 0244 PM CDT Thu Apr 13 2023 Areas affected...southern Florida Atlantic coastal areas Concerning...Severe potential...Watch unlikely Valid 131944Z - 132215Z Probability of Watch Issuance...20 percent SUMMARY...A couple of storms may intensify further and pose a risk for severe hail and wind through 5-7 PM EDT. Due to the anticipated sparse coverage of this threat, a severe weather watch may not be needed. But trends will continue to be monitored. DISCUSSION...Scattered thunderstorm development is well underway, with initiation ongoing near the Atlantic coast, mainly north of Miami, as well as across interior southern Florida, along the inland advancing sea-breeze from the Gulf of Mexico. This is occurring in the presence of sufficiently strong deep-layer shear (beneath 30 kt flow around 500 mb) for supercell structures, and sizable boundary-layer CAPE supported by insolation and dew points above 70F. While it appears that at least one or two of these storms could pose a risk for severe hail and wind during the next few hours, model output is suggestive that somewhat weaker mid/upper support for ascent relative to northern Florida Atlantic coastal areas may maintain a more isolated severe weather threat. ..Kerr/Leitman.. 04/13/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MFL...MLB... LAT...LON 28198066 27828024 26707998 25808016 25738074 26478087 27008074 28198066 Read more

WW 0133 Status Updates
STATUS REPORT ON WW 133 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 W MGR TO 30 WSW ABY. REMAINING VALID PORTION OF WW MAY BE ALLOWED TO EXPIRE AT 13/18Z. ..KERR..04/13/23 ATTN...WFO...TAE...MOB... STATUS REPORT FOR WT 133 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC065-079-123-131800- FL . FLORIDA COUNTIES INCLUDED ARE JEFFERSON MADISON TAYLOR GAC007-027-071-185-205-275-131800- GA . GEORGIA COUNTIES INCLUDED ARE BAKER BROOKS COLQUITT LOWNDES MITCHELL THOMAS THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 PM CDT Thu Apr 13 2023 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms capable of producing very large hail, and possibly a few damaging gusts, appear most likely to occur across portions of southeast Nebraska and into eastern Kansas Friday. ...Synopsis... While a weakening upper low shifts northeastward out of the Tennessee Valley, a larger trough will advance gradually eastward across the Intermountain West through the period. At the surface, the primary feature will be a cold front -- associated with the western upper trough -- which is forecast to make eastward/southeastward progress across the Plains through the period. ...Central Plains... While lack of moisture beneath an elevated mixed layer will allow rather stout capping to persist through much of the afternoon, a couple of storms may initiate near the advancing cold front by late in the day. Given amply strong/veering flow, in tandem with the steep lapse rates aloft, very large hail would be possible, along with a locally damaging gust or two. While storms may try to grow upscale locally, capping should tend to hinder robust/warm sector MCS development. To the cool side of the front, storms should increase across Kansas and Nebraska into the evening, as a southerly low-level jet develops. With these elevated storms, large hail will be a primary concern into the overnight hours. ...Southern Plains... In part due to modest boundary-layer moisture, a capping inversion at the base of an elevated mixed-layer will hinder afternoon convective development in most areas. A weak mid-level perturbation on the southeastern fringe of the advancing western U.S. trough may aid in a few local breaches of the cap -- with portions of eastern North Texas one area where a couple of cells may briefly develop. Any storm which could organize, would be capable of producing large hail and locally gusty winds. However, will maintain only low/conditional risk due to the strength of capping expected. ...The Carolinas vicinity... As a weakening upper low shifts northeastward out of the Tennessee Valley toward the central Appalachians, early-day convection is forecast to spread northeastward across the Carolinas and Mid-Atlantic region. In the wake of these storms, some diurnal heating to occur, beneath steepening lapse rates aloft associated with the upper system. This should lead to a regeneration of showers and scattered thunderstorms with a noted diurnal peak in coverage/intensity. While shear should remain somewhat limited, in terms of potential for well-organized storms, a few stronger multicell-type clusters may produce marginal hail, and wind gusts locally capable of tree damage. Risk should diminish through the evening hours. ..Goss.. 04/13/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Thu Apr 13 2023 Valid 141200Z - 151200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHERN HIGH PLAINS INTO NORTHWEST TEXAS... ...Southern High Plains... The previous forecast remains on track with only minor adjustments needed based on recent trends in hi-res ensemble guidance. See the previous discussion for additional details. ...Midwest... Periodic elevated conditions appear plausible for portions of northeast IA, southeast MN and WI tomorrow afternoon. While larger fuels remain only modestly dry per recent fuel analyses, fine fuels are likely receptive after multiple days of warm/dry weather. Winds will likely increase to 15 mph ahead of an approaching cold front, and some areas may see RH reductions to near 25%. Transient elevated conditions appear probable, but confidence in coverage/duration remains too limited for additional highlights at this time. ..Moore.. 04/13/2023 .PREV DISCUSSION... /ISSUED 0142 AM CDT Thu Apr 13 2023/ ...Synopsis... The mid-level jet will overspread southern New Mexico into West Texas on Friday. Trends in model guidance have been for the jet to be less intense the past few model cycles. However, a deep surface cyclone and strong low-level pressure gradients will still drive critical fire weather concerns within the southern High Plains. Confidence in critical fire weather is highest underneath the core of the mid-level jet within the Permian Basin into the South Plains. Still, strong winds will exist farther north into the Texas Panhandle as well. The latest fuel guidance from TICC shows ERCs nearing the 90th percentile in the Panhandle. While there is some potential for isolated thunderstorms on Thursday, the impacts should remain minimal and localized. As such, critical fire weather is anticipated in much of the Texas Panhandle. RH of near 10% to 15% will occur over a relatively broad area west of the dryline. Winds of 20-25 mph (with higher gusts) will also be common. The fire weather threat will be bounded by the dryline to the east and a southward-advancing cold front to the north. Winds will quickly change to northerly behind the cold front. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Wed Apr 12 21:16:02 UTC 2023.

No Mesoscale Discussions are in effect as of Wed Apr 12 21:16:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0249 PM CDT Wed Apr 12 2023 Valid 122000Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PORTIONS OF THE CENTRAL GULF COAST.... ...SUMMARY... Isolated damaging wind gusts and/or a tornado are possible along parts of the Gulf Coast late tonight into Thursday morning. ...20z Update... ...Southern FL Peninsula and Keys... A few stronger storms have been noted moving onshore over the far southern FL Peninsula and Keys this afternoon. Backed low-level flow along a northward moving warm front may support a low-end risk for transient supercells and a brief tornado through the afternoon. However, uncertainty on the coverage and longevity of any severe threat remains too high to introduce severe probabilities. Please see mesoscale discussion 504 for more information. Otherwise, no major changes have been made to the current outlook. Please see the previous discussion for additional details. ..Lyons/Dean.. 04/12/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Apr 12 2023/ ...Gulf Coast including southern portions MS/AL and FL Panhandle... With the mid-level portion of the cyclone centered along the southwest Louisiana coast this morning, the low-level circulation is expected to intensify and shift northward and reach coastal southeast Mississippi/far southwest Alabama vicinity by Thursday morning. However, it is noted that there are several-MB differences, even in the short term, with the progged deepening of the surface low and its northeast-peripheral strengthening wind field among model guidance (e.g. 12z NAM one of the more aggressive solutions). Even more modest-strength/slower solutions suggest that the near-coastal environment could become conducive to some severe-weather potential late tonight into Thursday, including locally damaging winds and a tornado risk. This will be as an increasingly moist air mass via a northward-shifting warm front approaches and moves inland. Mid-level winds will remain modest-strength, but strengthening low-level shear/SRH should be adequate for at least some near-coastal transient supercells, with the potential persisting into Thursday (see Day 2). Read more

The new well permit moratorium in the Hill Country Underground Water Conservation District was allowed to expire April 6. The moratorium took effect on July 12, 2022. The district gave a warning for “critical depletion” of the Ellenberger Aquifer, a large component of the county’s water supply. The well moratorium included irrigation, municipal and commercial purposes within Gillespie County. It had been renewed in 90-day increments since last summer as rainfall to replenish the aquifer has been scarce. Fredericksburg Standard (Texas), April 12, 2023

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0108 PM CDT Wed Apr 12 2023 Valid 131200Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR EASTERN NEW MEXICO TO SOUTHWEST NEBRASKA... The expected synoptic evolution remains on track per latest guidance, but a nearly-uniform increase in wind magnitudes is noted across the central Plains in most model solutions, indicative of a trend towards a stronger lee cyclone and stronger 925-850 mb flow than previously depicted. Consequently, confidence in widespread 15-25 mph winds has increased from the southern High Plains to parts of the upper MS River Valley. Diurnal RH reductions to 20-25% remain likely through the Plains/Midwest with 10-20% likely across the southern High Plains behind a sharpening dryline. Both the Elevated and Critical risk areas have been expanded to account for these trends. One complicating factor is the potential for strong to severe thunderstorms along the dryline from southwest NE to west TX during the late afternoon. High-based thunderstorms will pose a risk for strong to severe winds as well as a few dry lightning strikes given PWAT values generally around 0.6 inches or lower. Storm coverage remains uncertain, but the potential for lightning ignitions within a hot, dry, windy environment is noted across parts of the western Plains. ..Moore.. 04/12/2023 .PREV DISCUSSION... /ISSUED 0202 AM CDT Wed Apr 12 2023/ ...Synopsis... A broad upper trough will move through the Four Corners on Thursday and eject into the southern Plains around Friday morning. A strong low-pressure system in the central High Plains will continue to deepen and shift southeastward through the period. Strong surface winds are possible from the southern Plains into parts of the Midwest ahead of a cold front moving southward through the northern Plains. ...Southern High Plains into southeast Colorado... Surface winds of 15-25 mph appear possible from the foothills of the southern Rockies eastward to the surface trough/dryline. Several models indicate that RH could fall to 10-15% across the region. These meteorological factors will combine with drought-stressed fine fuels to promote critical fire weather conditions within a fairly narrow corridor east of the higher terrain. ...Central Plains into the Midwest... The surface pattern will be similar to Wednesday, though winds will likely be stronger. The driest conditions are most probable along the Foothills of Colorado into western portions of Kansas/Nebraska. There, RH of 15-20% with can be expected. Farther north and east into Iowa, RH of 20-25% appears possible. Some guidance shows at least local values in the teens. Winds across the central Plains/Midwest will be aided by enhanced 850 mb winds during the day. Fuels within the Foothills and Iowa do not appear to be critically dry. Impacts from drought have dried fuels in western Kansas into parts of Nebraska, but potential convection along the dryline may limit the duration of critical fire weather. Elevated fire weather is expected with locally critical fire weather remaining possible. ...Please see www.spc.noaa.gov/fire for graphic product... Read more