Severe Storms

WW 175 SEVERE TSTM FL GA CW 271845Z - 280200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 175 NWS Storm Prediction Center Norman OK 245 PM EDT Thu Apr 27 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Eastern Florida Peninsula Southeast Georgia Coastal Waters * Effective this Thursday afternoon and evening from 245 PM until 1000 PM EDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Thunderstorms are expected to intensify this afternoon from southeast Georgia into eastern Florida. Warm, humid conditions combined with favorable winds aloft will pose a risk of a few severe storms capable of large hail and damaging wind gusts. The severe thunderstorm watch area is approximately along and 35 statute miles east and west of a line from 20 miles northeast of Waycross GA to 55 miles south of Vero 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 174... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27025. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0310 PM CDT Thu Apr 27 2023 Valid 272000Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE LOWER MISSISSIPPI VALLEY AND PARTS OF FLORIDA... CORRECTED FOR GRAPHIC ...SUMMARY... Severe storms remain possible today over portions of the Lower Mississippi Valley as well as much of central and northern Florida. Damaging gusts, large hail, and a couple of tornadoes will all be possible. ...20Z Update... Severe probabilities have been cleared from deep-south TX since the cold front has pushed through the area, reducing convective potential. Severe probabilities have also been trimmed across portions of the Gulf Coast where an MCS have moved through and overturned/stabilized the airmass enough to reduce the severe threat. Otherwise, severe potential remains with the ongoing MCS moving across the central FL Panhandle, and with storms that can form on a sea-breeze boundary across northeast parts of the FL Peninsula. Damaging gusts, large hail, and a tornado or two remain possible. Severe potential remains with storms that can develop closer to the surface low over the Lower MS Valley, with damaging gusts and large hail the main threats. Lastly, a severe gust or two may accompany low-topped convection behind the cold front across the central Rockies/central High Plains, before nocturnal cooling reduces the steep low-level lapse rates and associated severe gust potential. ..Squitieri.. 04/27/2023 .PREV DISCUSSION... /ISSUED 1123 AM CDT Thu Apr 27 2023/ ...MS/AL/FL/GA... a large area of thunderstorms has been tracking eastward across the central Gulf Coast region this morning. The overall severe threat has diminished through the morning, but may reinvigorate this afternoon with slow daytime heating and moisture advection as storms will spread into southwest GA and the eastern FL Panhandle (WW 174). Forecast soundings and local VAD profiles show sufficient deep-layer shear for a few supercells capable of damaging wind gusts or perhaps a tornado or two through the afternoon. ...SE GA/FL... Strong daytime heating is occurring from southeast GA into the eastern FL Peninsula, where dewpoints in the 60s to lower 70s will yield afternoon MLCAPE values over 2000 J/kg. Scattered thunderstorms are expected to develop by mid-afternoon over the central Peninsula, as well as farther north with the approach of the convection over AL and the Panhandle. The environment in this area will be somewhat similar to yesterday, with a risk of a few supercells capable of large hail and damaging wind gusts. Storms should track offshore by mid-evening, ending the severe threat. ...AR/MS/TN/AL... Skies are beginning to slowly clear over parts of AR, beneath a cold upper low. This trend will continue through the afternoon, leading to a region of moderate CAPE and steep mid-level lapse rates. Most CAM solutions agree on the development of scattered afternoon thunderstorms from central AR eastward into west TN and northern MS. This region will be in the exit region of a mid-level jet max, and in an area of sufficient vertical shear for organized updrafts. The strongest cells will be capable of large hail for few hours this afternoon and evening. ...South TX... A cold front is sagging southward across Deep South TX today. Low-level winds ahead of the front have shifted to northerly, reducing frontal convergence and likely limiting the coverage of afternoon thunderstorms. Nevertheless, an isolated storm or two remains possible. Any storms that form would be in a very moist and unstable environment, with sufficient flow aloft to promote supercell structures. Large to very large hail would be possible. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Thu Apr 27 2023 Valid 281200Z - 291200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEAST ARIZONA AND SOUTHWEST NEW MEXICO... The previous forecast remains on track, and only minor changes were made to the Critical area based on the latest high-resolution guidance. For details on the Day 2/Friday fire-weather threat, see the previous discussion below. ..Weinman.. 04/27/2023 .PREV DISCUSSION... /ISSUED 0132 AM CDT Thu Apr 27 2023/ ...Synopsis... A sharp, positively tilted mid-level trough will move south across the Rockies during the day on Friday. A surface low will move south ahead of this mid-level wave. In the wake of this trough, a strong area of surface high pressure will build in across the Rockies. This will result in a tight pressure gradient across the southern Rockies and Southwest, resulting in strong northerly winds. In addition to this surface pressure gradient, a deeply mixed airmass will be present across western New Mexico and eastern Arizona. This will also lead to strengthening surface wind speeds in a region with single-digit relative humidity. Therefore, critical fire weather conditions are expected across southeast Arizona and southwest New Mexico where there is the best overlap between strong winds, low relative humidity, and dry 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 1230 PM CDT Thu Apr 27 2023 Valid 281200Z - 291200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF CENTRAL TEXAS... ...SUMMARY... Scattered storms are forecast to produce damaging hail from late afternoon through evening from north-central Texas to the middle and lower Rio Grande Valley. Isolated strong to severe storms may also occur over parts of the Southeast into the central Appalachians. ...Synopsis... A positively tilted upper trough will progress southward into the Southern Plains from the central Rockies as a mid-level impulse traverses the Southeast and Carolina Piedmont region tomorrow/Friday. The low-level mass response in both of these regions will be surface low development, with enhanced low-level convergence and moisture advection supporting an increase in convective coverage. The increase in boundary layer flow/shear in both regions will also support storm organization, with strong to severe storm development likely, especially in north-central to south-central TX. ...Southern Plains... On Friday afternoon, low to mid 60s F surface dewpoints will advect northward across TX, from the Gulf Coast to the Red River. Up to 9 C/km mid-level lapse rates will overspread the low-level moisture plume by afternoon peak heating, contributing to 2000-3500 J/kg MLCAPE. Around this time, a surface cold front is expected to merge with a dryline progressing eastward from the TX Hill Country, resulting in convective initiation and rapid intensification. Forecast soundings depict elongated hodographs with modest low-level curvature ahead of the cold front/dryline intersection, suggesting that supercells will be the initial mode before storm mergers result in linear segments or even a possible MCS. The elongated hodographs and breadth of buoyancy above the freezing level suggest that large hail will be the primary threat with supercells, with a couple of instances of 3+ inch stones possible. A couple of tornadoes also cannot be ruled out with some of the more dominant, longer-lasting supercells. However, the predominant severe threat should be severe gusts once storm/cold pool mergers take place. ...Florida to the Carolina Piedmont... A surface low will deepen over OH with the passage of a mid-level perturbation, supporting modest low-level moisture return beneath 6.5-7.5 C/km low to mid-level lapse rates from the eastern OH Valley, to the Carolina Piedmont and the Florida Peninsula region. Surface dewpoints are expected to range from the mid 50s in the central Appalachians to near 70 F across southern GA and FL, contributing to MLCAPE of 750 J/kg in the eastern OH Valley to over 1500 J/kg across the Southeast. In combination with this buoyancy, southerly low-level flow overspread by 40+ kts of 500 mb westerly winds will contribute to elongated hodographs. These hodographs, along with the aforementioned buoyancy, will support organized thunderstorm development, with a couple of damaging gusts and large hail the main threats. ..Squitieri.. 04/27/2023 Read more

MD 0624 CONCERNING SEVERE THUNDERSTORM WATCH 168... FOR FLORIDA PENINSULA
Mesoscale Discussion 0624 NWS Storm Prediction Center Norman OK 0333 PM CDT Wed Apr 26 2023 Areas affected...Florida Peninsula Concerning...Severe Thunderstorm Watch 168... Valid 262033Z - 262230Z The severe weather threat for Severe Thunderstorm Watch 168 continues. SUMMARY...A threat for large/very-large hail remains across the Florida Peninsula. Additional storms may develop in western/central Florida through the remainder of the afternoon. DISCUSSION...The strongest storms this afternoon have been near the Atlantic coast. Supercell storms in that area have remained east of the sea breeze boundary. Large hail and damaging winds have been reported with this activity over the last 2 hours. Convection along the Gulf breeze boundary continues to build. Storms have recently initiated east of Sarasota. Additional storms are possible through the afternoon, particularly if the sea breezes interact with one another. Shear and mid-level lapse rates will remain sufficient to support a large to very-large (2+ in.) hail threat along with isolated damaging winds. ..Wendt.. 04/26/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MFL...MLB...TBW...JAX... LAT...LON 27338213 28358253 29488232 29578142 28678060 27858033 27378011 26818011 26078016 25648032 25528049 25638093 26668165 26618158 27338213 Read more

WW 0168 Status Updates
STATUS REPORT ON WW 168 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..04/26/23 ATTN...WFO...JAX...MLB...MFL...TBW... STATUS REPORT FOR WS 168 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS FLC001-009-011-027-035-043-049-051-055-061-069-083-085-086-093- 095-097-099-105-107-111-117-119-127-262140- FL . FLORIDA COUNTIES INCLUDED ARE ALACHUA BREVARD BROWARD DESOTO FLAGLER GLADES HARDEE HENDRY HIGHLANDS INDIAN RIVER LAKE MARION MARTIN MIAMI-DADE OKEECHOBEE ORANGE OSCEOLA PALM BEACH POLK PUTNAM ST. LUCIE SEMINOLE SUMTER VOLUSIA AMZ550-552-555-610-630-650-651-262140- CW . ADJACENT COASTAL WATERS INCLUDED ARE FLAGLER BEACH TO VOLUSIA-BREVARD COUNTY LINE 0-20 NM VOLUSIA-BREVARD COUNTY LINE TO SEBASTIAN INLET 0-20 NM Read more

WW 168 SEVERE TSTM FL CW 261810Z - 270100Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 168 NWS Storm Prediction Center Norman OK 210 PM EDT Wed Apr 26 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of The Florida Peninsula Coastal Waters * Effective this Wednesday afternoon and evening from 210 PM until 900 PM EDT. * Primary threats include... Scattered large hail likely with isolated very large hail events to 3 inches in diameter possible Scattered damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...Thunderstorms are expected to increase in coverage and intensity this afternoon, while posing a threat for very large hail and damaging winds. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 30 miles east of Gainesville FL to 10 miles south southwest of Miami FL. 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. && AVIATION...A few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 29020. ...Gleason/Hart Read more

WW 0169 Status Updates
STATUS REPORT ON WW 169 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..LYONS..04/26/23 ATTN...WFO...FWD...SJT...EWX... STATUS REPORT FOR WT 169 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC001-027-035-049-053-059-083-093-099-133-139-143-145-161-193- 213-217-221-251-281-289-293-299-309-331-333-349-395-411-425-491- 262140- TX . TEXAS COUNTIES INCLUDED ARE ANDERSON BELL BOSQUE BROWN BURNET CALLAHAN COLEMAN COMANCHE CORYELL EASTLAND ELLIS ERATH FALLS FREESTONE HAMILTON HENDERSON HILL HOOD JOHNSON LAMPASAS LEON LIMESTONE LLANO MCLENNAN MILAM MILLS NAVARRO ROBERTSON SAN SABA SOMERVELL WILLIAMSON 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 169 TORNADO TX 261950Z - 270300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 169 NWS Storm Prediction Center Norman OK 250 PM CDT Wed Apr 26 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central Texas * Effective this Wednesday afternoon and evening from 250 PM until 1000 PM CDT. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Widespread large hail and isolated very large hail events to 3.5 inches in diameter likely Scattered damaging winds likely with isolated significant gusts to 75 mph possible SUMMARY...Supercells capable of producing multiple tornadoes, very large hail, and damaging/severe winds are expected to develop and spread southeastward this afternoon and evening. Some of the tornadoes could be strong, and damaging winds will likely become a greater concern this evening as thunderstorms grow upscale into a bowing cluster. The tornado watch area is approximately along and 60 statute miles north and south of a line from 20 miles west southwest of Brownwood TX to 50 miles north of Huntsville TX. 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 168... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 3.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 600. Mean storm motion vector 28035. ...Gleason/Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0241 PM CDT Wed Apr 26 2023 Valid 262000Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF CENTRAL TEXAS AND THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... A few tornadoes (possibly some strong), very large/destructive hail, and severe thunderstorm gusts are expected over parts of central Texas this afternoon and evening. Very large hail and damaging winds remain a threat over parts of Florida into far southeast Georgia this afternoon and early evening. ...20Z Update... Adjustments were made to the Category 3/Enhanced risk area (and associated probabilities) in central TX to align with the warm sector along and just south of an outflow boundary which is behaving like an effective warm front. Storms that form just ahead of the dryline and can traverse the outflow boundary area will likely become supercells capable of very large hail, hurricane-force wind gusts, and a couple of tornadoes. Any storms that can traverse the boundary for a long enough period of time may ingest locally higher amounts of streamwise vorticity, which may support the development of a strong tornado. Please see MCD #0623 for more information. The Category 2/Slight risk across northern FL was extended northward to include portions of far southeast GA, where supercell structures have produced reported golfball size hail, and where MRMS MESH suggests that significant severe hail may be occurring. Given the presence of steep lapse rates and adequate deep-layer shear, the severe hail threat may continue into the early evening hours. Finally, the Category 2/Slight risk in Texas was expanded farther east into central LA. Here, a cluster of storms may persist into the overnight hours and support short bowing structures capable of damaging gusts. ..Squitieri.. 04/26/2023 .PREV DISCUSSION... /ISSUED 1125 AM CDT Wed Apr 26 2023/ ...Texas into the Lower Mississippi Valley... Elevated convection is ongoing late this morning across north-central TX and far southern OK. This activity is related to low-level warm advection and ascent preceding an upper trough over the southern High Plains. Recent surface observations show a warm front draped across north-central into east TX. Most 12Z guidance continues to suggest that this warm front will attempt to lift northward this afternoon as the upper trough/low ejects slowly eastward across the southern Plains. A surface dryline is also forecast to mix eastward across parts of west into central TX, and provide a focus for robust convective development this afternoon. Convective evolution across north/central TX this afternoon will be somewhat complicated by the ongoing convection near the Red River. These thunderstorms will probably tend to limit the northward advance of the warm front. Still, moderate to locally strong instability appears likely to develop by peak heating this afternoon south of the warm front and east of the dryline as steep mid-level lapse rates/an EML overspread the warm sector, and as surface dewpoints generally increase into the mid to upper 60s. Current expectations are for multiple surface-based supercells to initiate along/near composite the outflow/warm front/dryline intersection early this afternoon, probably no later than 19-20Z. Given the presence of steep mid-level lapse rates and 40-50 kt of deep-layer shear, this initially semi-discrete convection will pose a threat for very large hail (2-3+ inch diameter) as it spreads east-southeastward this afternoon across north TX. The threat for a few tornadoes will also exist, as low-level flow will strongly veer from east-southeasterly at low levels to westerly at mid levels, enhancing the low-level hodograph and effective SRH. Strong tornado potential should remain focused with any supercell that can remain anchored along the warm front. The initially semi-discrete supercells will likely grow upscale into a bowing complex/MCS by early evening. As this mode transition occurs, the threat for severe/damaging winds will increase, with some potential for significant (75+ mph) gusts across north-central into east TX. 12Z guidance shows this MCS continuing into LA and parts of central/southeast TX this evening/overnight. While some decrease in updraft intensity may eventually occur, there will probably be a continued threat for scattered damaging winds given a reservoir of favorable buoyancy. Some chance for a couple of supercells may also exist over central TX this afternoon, driven by modest low-level warm advection. If robust thunderstorms can form, they would pose a threat for all severe hazards, including very large hail. Have therefore expanded the Slight Risk southward to include more of central/southeast TX to account for this severe potential. An isolated severe threat should also persist tonight into portions of the lower MS Valley, as generally linear convection spreads eastward from TX. ...Florida... Based on recent visible satellite imagery, mostly clear/sunny conditions are present over the FL Peninsula. The eastern extent of a remnant EML, shown in the fairly steep 700-500 mb lapse rates on the 12Z TBW/15Z XMR soundings, has overspread much of the FL Peninsula. Robust diurnal heating of a rich low-level airmass will contribute to a moderately to strongly unstable airmass, with MLCAPE generally around 2000-2500+ J/kg. Even with low-level winds expected to remain fairly weak, enhanced mid/upper-level flow will foster 40-50 kt of effective bulk shear and updraft organization. Compared to the past two days, it appears likely that multiple supercells capable of producing both very large hail and strong/damaging winds will develop this afternoon over the northern/central FL Peninsula along both sea breezes and residual outflow boundaries, and subsequently spread southward through the early evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0149 PM CDT Wed Apr 26 2023 Valid 271200Z - 281200Z The previous forecast (see below) remains on track, and no changes were needed with this update. ..Weinman.. 04/26/2023 .PREV DISCUSSION... /ISSUED 0145 AM CDT Wed Apr 26 2023/ ...Synopsis... Moderate northwesterly flow will remain across New Mexico on Thursday and deep mixing is anticipated. This will lead to dry and breezy conditions during the afternoon and early evening hours. Winds of 15 to 20 mph are expected with relative humidity of 8 to 12 percent within the Elevated area across northwest and central New Mexico. Much stronger winds are expected farther northwest across the Great Basin where relative humidity will also be in the teens. However, fuels are still moist across most of this region, and therefore, no fire weather headlines are justified. ...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 1226 PM CDT Wed Apr 26 2023 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF DEEP SOUTH TEXAS AND PORTIONS OF SOUTHERN LOUISIANA INTO SOUTHWESTERN GEORGIA AND THE FLORIDA PANHANDLE... ...SUMMARY... Scattered severe storms are expected along much of the Gulf Coast Thursday, from portions of southern Texas and southern Louisiana into the Florida Panhandle. Damaging gusts, large hail, and a few tornadoes will all be possible. ...Synopsis... A mid-level trough will sweep across the Southeast U.S. as a second upper trough amplifies over the central Rockies tomorrow/Thursday. Modest surface-low intensification is likely by late morning to early afternoon across the Lower MS Valley, which should encourage an increase in low-level moisture advection, buoyancy and flow/shear along the Gulf Coast. In addition to an increase in convective coverage, strong to severe thunderstorm development is likely, with all severe hazards possible. Across the central Rockies into the central High Plains, deep-layer ascent with the deepening upper trough will encourage enough lift within a marginally buoyant airmass to promote at least scattered thunderstorms, some of which may become strong to locally severe. ...Gulf Coast Region... Strong to potentially severe thunderstorms should be ongoing at the start of the period across far eastern TX into LA ahead of a cold front sweeping southward across the Southern Plains. As the surface low gradually intensifies and drifts from the Lower MS Valley to the TN Valley during the late morning/afternoon hours, the cold front should continue to sag south/eastward. Increasing surface-850 mb flow, moisture and convergence ahead of the storms should support an increase of MLCAPE to 1000 J/kg along with convective coverage and intensity by late morning/early afternoon. Several storms should merge into a QLCS, with the possibility of a few discrete storms also developing ahead of the line. Damaging gusts should be the main threat with the QLCS, though a few tornadoes may also occur given modest low-level hodograph curvature. The latest high-resolution guidance consensus also depicts a couple of isolated splitting supercell structures initiating off of the trailing cold front across deep south TX during the late morning/early afternoon. Before moving offshore, the supercells may produce damaging gusts and large hail. 8+ C/km lapse rates atop near 70 F surface dewpoints will support 2000-3000 J/kg MLCAPE amid elongated, straight hodographs. As such, an instance or two of 2+ inch diameter hail cannot be ruled out. Lastly, guidance consensus also depicts discrete storms (perhaps transient supercells) initiating off of a sea-breeze boundary across northeast FL during the afternoon. 2000+ J/kg MLCAPE amid elongated hodographs suggest that isolated damaging gusts and large hail may accompany one or two of the stronger storms. ...Lower MS Valley... As the primary round of thunderstorms progresses along the Gulf Coast through the afternoon, a second cluster of strong storms is expected to develop closer to the surface low, beneath the core of a 500 mb jet streak. Colder temperatures and increasing speed shear above 700 mb will support 7.5+ C/km mid-level lapse rates amid elongated, straight hodographs. As such, a few storms should become organized enough to support an isolated severe threat through the afternoon, with large hail and damaging gusts the main threats. ...Central Rockies/Central High Plains... By mid afternoon, bands of low-topped thunderstorms are expected to develop behind the cold front as cold temperatures aloft/8+ C/km mid-level lapse rates overspreads a dry, deeply mixed boundary layer. Forecast soundings in this dry post-cold-frontal regime depict very thin, meager CAPE profiles. Nonetheless, 30-40 F surface temperature/dewpoint spreads and associated boundary-layer lapse rates approaching 9 C/km may encourage efficient evaporative cooling in the stronger storms to support isolated strong surface winds gusts, one or two of which may reach severe limits. ..Squitieri.. 04/26/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1143 AM CDT Wed Apr 26 2023 Valid 261700Z - 271200Z Only minor changes were made to the Elevated highlights based on the latest observational data. For details, see the previous discussion below. ..Weinman.. 04/26/2023 .PREV DISCUSSION... /ISSUED 0144 AM CDT Wed Apr 26 2023/ ...Synopsis... A mid-level trough will shift southeastward from southern Colorado to the southern Plains today. West of this trough, moderate northwesterly flow will be present across the Southwest. This will overspread a deeply mixed boundary layer across southeast New Mexico with a few hours of elevated to potentially critical fire weather conditions, before a southward-surging cold front arrives in the area with much colder temperatures. Elsewhere, cool and or moist conditions will preclude fire weather concerns. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0166 Status Updates
STATUS FOR WATCH 0166 HAS NOT BEEN ISSUED YET Read more

WW 166 SEVERE TSTM OK TX 252130Z - 260400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 166 NWS Storm Prediction Center Norman OK 430 PM CDT Tue Apr 25 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Oklahoma Panhandle Northwest Texas and Panhandle * Effective this Tuesday afternoon and evening from 430 PM until 1100 PM CDT. * Primary threats include... Isolated very large hail events to 2 inches in diameter possible Isolated damaging wind gusts to 70 mph possible A tornado or two possible SUMMARY...A few supercells should develop east-southeast across the Panhandles into northwest Texas this evening. The severe thunderstorm watch area is approximately along and 65 statute miles east and west of a line from 30 miles west northwest of Guymon OK to 65 miles southeast of Lubbock TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). 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 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean storm motion vector 29025. ...Grams Read more

No watches are valid as of Tue Apr 25 21:29:02 UTC 2023.

MD 0614 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHWEST OKLAHOMA...WESTERN NORTH TEXAS...PARTS OF SOUTH PLAINS
Mesoscale Discussion 0614 NWS Storm Prediction Center Norman OK 0343 PM CDT Tue Apr 25 2023 Areas affected...Southwest Oklahoma...western North Texas...Parts of South Plains Concerning...Severe potential...Watch possible Valid 252043Z - 252245Z Probability of Watch Issuance...60 percent SUMMARY...Observational trends in southwest Oklahoma into parts of the South Plains suggest increased confidence in storm development this afternoon. Large/very-large hail and damaging winds would be the primary threats. A watch is possible depending on convective trends over the next two hours. DISCUSSION...While cloud cover has been present much of the day in the western North Texas vicinity, some erosion has occurred along/near the warm front and near the Snyder, TX vicinity this afternoon. This has allowed temperatures to warm more than guidance had been suggesting. Recent visible satellite trends in southwest Oklahoma show deepening cumulus along the warm front near Altus. With some high resolution guidance (including the WoFS) indicating potential storm development, there is increased confidence in the potential for a supercell or two to develop. MLCAPE nearing 1000 J/kg and effective shear around 40 kts will support a threat for large/very-large hail as well as damaging wind gusts. Farther south, near Snyder, there is less confidence in development. However, temperatures will continue to warm and the West Texas Mesonet data available shows convergence along the differential heating boundary. A similar threat for large/very-large hail and damaging winds would exist here as well. Additional supercells are also possible as the dryline sharpens farther to the west. The current environment would suggest the tornado threat would remain relatively low this afternoon. Should discrete activity be sustained into early evening, some increase in tornado potential would occur with the strengthening of the low-level jet. A watch is possible this afternoon depending on convective trends over the next 1-2 hours. ..Wendt/Gleason.. 04/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN...SJT...LUB...AMA...MAF... LAT...LON 32610116 33130144 33860165 34890151 35180062 35150002 35039925 34769885 33939871 32409991 32290042 32330076 32610116 Read more

MD 0613 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN HIGH PLAINS
Mesoscale Discussion 0613 NWS Storm Prediction Center Norman OK 0301 PM CDT Tue Apr 25 2023 Areas affected...Southern High Plains Concerning...Severe potential...Watch unlikely Valid 252001Z - 252200Z Probability of Watch Issuance...20 percent SUMMARY...Widely scattered storms may produce isolated large hail and damaging winds. Limited moisture/buoyancy should keep storm intensity marginal. A watch appears unlikely at this time. DISCUSSION...As the upper-level trough approaches the southern High Plains this afternoon, convection along a surface trough/developing dryline has continued to slowly deepen. Moisture is very limited within the region as dewpoints are in the upper 30s F to mid 40s F. Lapse rates at low/mid-levels are steep enough to support isolated large hail and damaging winds despite the modest MLCAPE (near 500 J/kg). Storm intensity is expected to remain marginal until this activity encounters greater low-level moisture to the east. A watch is not currently expected. ..Wendt/Gleason.. 04/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LUB...AMA...PUB...ABQ... LAT...LON 34230377 37030429 37610401 37690312 36170214 35180196 34400256 34030325 34230377 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Apr 25 2023 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF TEXAS AND SOUTHWEST OKLAHOMA... ...SUMMARY... Severe thunderstorms are possible mainly late this afternoon into tonight over parts of the southern Plains, with a risk for large to very large hail, damaging winds, and perhaps a couple of tornadoes. ...20Z Update... ...Southern Plains... Recent surface analysis reveals a developing lee low over northeast NM, with a strengthening warm front extending southeastward across the OK/TX Panhandles and into southwest OK then eastward along the Red River. Convective initiation has already occurred in the vicinity of the lee low, with these storms expected to move eastward in the TX/OK Panhandles over the next few hours. Low-level moisture is meager but cold temperatures aloft will still support modest buoyancy and a few stronger storms. Mid 50s dewpoints have reached southwest OK, with the expectation that convective initiation will eventually occur in this region this afternoon/evening. Surface temperatures are cool, but mid-level lapse rates are steep enough to support isolated severe thunderstorms capable of hail. As mentioned in the previous outlook, initiation farther south in southwest TX remain uncertain due to strong capping. The cloud cover has now dissipated and the surface temperature at SJT has climbed to 78, which is 6 degrees warmer than recent RAP forecast soundings. Additional warming is likely, but the boundary layer will further mix as well. Given the EML and moderate mid-level flow, a conditional risk for very large hail exists. ...Florida... Thunderstorms are expected to continue across FL for the next few hours until nocturnal stabilization sets in. Environmental conditions support storms capable of isolated hail and/or a few stronger gusts. Refer to MCD #612 for additional information. ..Mosier.. 04/25/2023 .PREV DISCUSSION... /ISSUED 1124 AM CDT Tue Apr 25 2023/ ...Southern Plains... An upper trough/low centered over the Great Basin and central Rockies this morning will advance south-southeastward towards the Four Corners by this evening, and will eventually reach the southern High Plains late tonight. A subtle, southern-stream perturbation over northern Mexico will move eastward across west/central TX through the day. At the surface, weak cyclogenesis should occur across eastern NM this afternoon/evening. Low-level moisture, characterized by generally low 50s to low 60s surface dewpoints, will continue streaming northward today along/south of a warm front and east of a dryline. Convective potential and evolution across the warm sector this afternoon through tonight remains unclear owing to weak/nebulous large-scale ascent. Still, the best signal for thunderstorm initiation appears to be across the higher terrain of southeastern CO and northeastern NM this afternoon with weak low-level upslope flow occurring and ascent from the approaching upper trough. This activity should spread generally southeastward across the OK/TX Panhandles and eventually northwest TX. Although low-level moisture will remain rather limited, the presence of steep mid-level lapse rates and 30-40 kt of deep-layer shear should prove sufficient for thunderstorm organization, including the potential for multiple supercells posing a threat for mainly large hail. Confidence in greater coverage of intense convection has increased enough to expand the Slight Risk farther northwest into parts of the TX Panhandle. These thunderstorms should continue east-southeastward towards northwest TX and southwestern OK this evening/tonight. The activity in OK will probably tend to become elevated to the north of the warm front, but it may still pose some threat for hail. Gusty winds will be possible with any clusters that can persist with eastward extent tonight from northwest into central TX. The prospect for convective initiation along the dryline this afternoon from northwest to central TX still appears rather conditional, as a pronounced cap noted on 12Z soundings from MAF and DRT will be slow to erode and potentially difficult to breach. Widespread low-level cloud cover noted on morning visible satellite imagery east of the dryline will need to mix out to some extent to generate sufficient diurnal heating to support parcels being lifted near/to their LFCs. A somewhat better chance for surface-based convective development may be across northwest into western north TX, where some cloud breaks and filtered daytime heating have already been observed. If thunderstorms can form and be sustained across this region, they will likely be supercells and pose a threat for large to very large hail initially given the presence of moderate instability, steep mid-level lapse rates, and sufficient effective bulk shear. As a southerly low-level jet modestly strengthens this evening, there may also be a narrow, 2-4 hour window (from roughly 22-02Z) for a couple of tornadoes with any supercell that can remain surface based. The possibility of open warm sector development this afternoon also remains apparent over portions of coastal/southeast TX. If this activity forms, it would likely be tied to weak low-level warm advection and daytime heating on the southern fringe of persistent cloud cover. Any thunderstorms that can persist in this regime may pose a threat for large hail and damaging winds. Based on signals in 12Z guidance on where this convection may develop, have expanded the Slight Risk a little southeastward towards the middle TX Coast. ...Florida... Generally zonal flow aloft will persist over the FL Peninsula today. With robust diurnal heating expected, scattered thunderstorms should once again develop along both the Atlantic and Gulf Coast sea breezes this afternoon, and to the south of a remnant front draped across the north/central FL Peninsula. While low-level winds will remain weak, strengthening west-southwesterly flow at mid/upper levels should support around 30-35 kt of deep-layer shear. This should be sufficient for some updraft organization, including the potential for a mix of multicells and perhaps marginal supercell structures. With seasonably cool mid-level temperatures present, some of these thunderstorms could pose an isolated threat for severe hail and damaging wind gusts this afternoon and early evening. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0256 PM CDT Tue Apr 25 2023 Valid 252000Z - 261200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF TEXAS AND SOUTHWEST OKLAHOMA... ...SUMMARY... Severe thunderstorms are possible mainly late this afternoon into tonight over parts of the southern Plains, with a risk for large to very large hail, damaging winds, and perhaps a couple of tornadoes. ...20Z Update... ...Southern Plains... Recent surface analysis reveals a developing lee low over northeast NM, with a strengthening warm front extending southeastward across the OK/TX Panhandles and into southwest OK then eastward along the Red River. Convective initiation has already occurred in the vicinity of the lee low, with these storms expected to move eastward in the TX/OK Panhandles over the next few hours. Low-level moisture is meager but cold temperatures aloft will still support modest buoyancy and a few stronger storms. Mid 50s dewpoints have reached southwest OK, with the expectation that convective initiation will eventually occur in this region this afternoon/evening. Surface temperatures are cool, but mid-level lapse rates are steep enough to support isolated severe thunderstorms capable of hail. As mentioned in the previous outlook, initiation farther south in southwest TX remain uncertain due to strong capping. The cloud cover has now dissipated and the surface temperature at SJT has climbed to 78, which is 6 degrees warmer than recent RAP forecast soundings. Additional warming is likely, but the boundary layer will further mix as well. Given the EML and moderate mid-level flow, a conditional risk for very large hail exists. ...Florida... Thunderstorms are expected to continue across FL for the next few hours until nocturnal stabilization sets in. Environmental conditions support storms capable of isolated hail and/or a few stronger gusts. Refer to MCD #612 for additional information. ..Mosier.. 04/25/2023 .PREV DISCUSSION... /ISSUED 1124 AM CDT Tue Apr 25 2023/ ...Southern Plains... An upper trough/low centered over the Great Basin and central Rockies this morning will advance south-southeastward towards the Four Corners by this evening, and will eventually reach the southern High Plains late tonight. A subtle, southern-stream perturbation over northern Mexico will move eastward across west/central TX through the day. At the surface, weak cyclogenesis should occur across eastern NM this afternoon/evening. Low-level moisture, characterized by generally low 50s to low 60s surface dewpoints, will continue streaming northward today along/south of a warm front and east of a dryline. Convective potential and evolution across the warm sector this afternoon through tonight remains unclear owing to weak/nebulous large-scale ascent. Still, the best signal for thunderstorm initiation appears to be across the higher terrain of southeastern CO and northeastern NM this afternoon with weak low-level upslope flow occurring and ascent from the approaching upper trough. This activity should spread generally southeastward across the OK/TX Panhandles and eventually northwest TX. Although low-level moisture will remain rather limited, the presence of steep mid-level lapse rates and 30-40 kt of deep-layer shear should prove sufficient for thunderstorm organization, including the potential for multiple supercells posing a threat for mainly large hail. Confidence in greater coverage of intense convection has increased enough to expand the Slight Risk farther northwest into parts of the TX Panhandle. These thunderstorms should continue east-southeastward towards northwest TX and southwestern OK this evening/tonight. The activity in OK will probably tend to become elevated to the north of the warm front, but it may still pose some threat for hail. Gusty winds will be possible with any clusters that can persist with eastward extent tonight from northwest into central TX. The prospect for convective initiation along the dryline this afternoon from northwest to central TX still appears rather conditional, as a pronounced cap noted on 12Z soundings from MAF and DRT will be slow to erode and potentially difficult to breach. Widespread low-level cloud cover noted on morning visible satellite imagery east of the dryline will need to mix out to some extent to generate sufficient diurnal heating to support parcels being lifted near/to their LFCs. A somewhat better chance for surface-based convective development may be across northwest into western north TX, where some cloud breaks and filtered daytime heating have already been observed. If thunderstorms can form and be sustained across this region, they will likely be supercells and pose a threat for large to very large hail initially given the presence of moderate instability, steep mid-level lapse rates, and sufficient effective bulk shear. As a southerly low-level jet modestly strengthens this evening, there may also be a narrow, 2-4 hour window (from roughly 22-02Z) for a couple of tornadoes with any supercell that can remain surface based. The possibility of open warm sector development this afternoon also remains apparent over portions of coastal/southeast TX. If this activity forms, it would likely be tied to weak low-level warm advection and daytime heating on the southern fringe of persistent cloud cover. Any thunderstorms that can persist in this regime may pose a threat for large hail and damaging winds. Based on signals in 12Z guidance on where this convection may develop, have expanded the Slight Risk a little southeastward towards the middle TX Coast. ...Florida... Generally zonal flow aloft will persist over the FL Peninsula today. With robust diurnal heating expected, scattered thunderstorms should once again develop along both the Atlantic and Gulf Coast sea breezes this afternoon, and to the south of a remnant front draped across the north/central FL Peninsula. While low-level winds will remain weak, strengthening west-southwesterly flow at mid/upper levels should support around 30-35 kt of deep-layer shear. This should be sufficient for some updraft organization, including the potential for a mix of multicells and perhaps marginal supercell structures. With seasonably cool mid-level temperatures present, some of these thunderstorms could pose an isolated threat for severe hail and damaging wind gusts this afternoon and early evening. Read more