Severe Storms

MD 1264 CONCERNING TORNADO WATCH 374...379...381... FOR NORTH-CENTRAL KENTUCKY...SOUTHERN INDIANA...SOUTHWEST OHIO
Mesoscale Discussion 1264 NWS Storm Prediction Center Norman OK 0447 PM CDT Sun Jun 25 2023 Areas affected...North-central Kentucky...southern Indiana...southwest Ohio Concerning...Tornado Watch 374...379...381... Valid 252147Z - 252345Z The severe weather threat for Tornado Watch 374, 379, 381 continues. SUMMARY...Tornado risk will likely increase over the next few hours with supercells moving east across portions of Tornado Watches 374, 379, and 381. DISCUSSION...Regional radar composite at 2140z shows several discrete supercells from extreme northwest KY northeast into southern Indiana, with a history of very large hail. Over the next 2 to 4 hours, the mesoscale environment will likely become more conducive for tornado development as low-level winds strengthen in association with an upper-level low over Lake Michigan. The environment remains moderately to strongly unstable and with ample deep-layer shear to support continued supercell structures. RAP-based STP values of 6 to locally 8 are forecast in the 23z-02z time frame across much of the discussion area, supporting an increased tornado risk for supercells remaining discrete while moving east-southeast. Given this favorable environment, a strong tornado will be possible. ..Bunting.. 06/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...IND...PAH... LAT...LON 38798661 39158592 39318514 39208438 38888402 38318404 37918431 37558465 37428490 37208537 37278678 37938728 38408703 38798661 Read more

MD 1263 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF NORTHEASTERN ARKANSAS...SOUTHERN MISSOURI...INTO WESTERN TENNESSEE/KENTUCKY.
Mesoscale Discussion 1263 NWS Storm Prediction Center Norman OK 0445 PM CDT Sun Jun 25 2023 Areas affected...portions of northeastern Arkansas...southern Missouri...into western Tennessee/Kentucky. Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 252145Z - 252315Z Probability of Watch Issuance...80 percent SUMMARY...New thunderstorm development and ongoing supercells capable of very large hail and damaging wind gusts are likely this evening. A Watch will likely be needed. DISCUSSION...Across portions of the mid to lower MS Valley, broad-scale ascent from an approaching upper-low and speed max was beginning to impinge on the northern fringes of a broad warm sector. Late afternoon visible satellite imagery showed cumulus towers slowly deepening along a wind shift boundary demarcating the northern extent of the warm and very moist air mass. Mid to upper 70s dewpoints and 90s F surface temperatures beneath steep mid-level lapse rates are supporting large buoyancy with 3500-4500 J/kg of MLCAPE. Atop the unstable boundary layer, 40-50 kt of effective shear observed from area VADs will support storm reorganization into supercells and linear clusters. With substantial instability and vertical shear, large to very large hail and damaging wind gusts will be likely with severe storms that form this afternoon/evening. A Severe Thunderstorm Watch is likely needed. ..Lyons/Guyer.. 06/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LMK...OHX...PAH...MEG...LZK... LAT...LON 36199117 36619018 37108876 37258825 37028688 35768769 35068892 34709022 34449100 34489123 36199117 Read more

MD 1262 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHEASTERN WY...FAR NORTHEASTERN CO...AND THE NE PANHANDLE
Mesoscale Discussion 1262 NWS Storm Prediction Center Norman OK 0438 PM CDT Sun Jun 25 2023 Areas affected...Parts of southeastern WY...far northeastern CO...and the NE Panhandle Concerning...Severe potential...Watch unlikely Valid 252138Z - 252345Z Probability of Watch Issuance...20 percent SUMMARY...An isolated strong to severe storm or two is possible this afternoon/early evening. Marginally severe hail and locally severe gusts are the primary concerns. DISCUSSION...Isolated convective initiation is underway along the higher terrain in southeastern Wyoming this afternoon -- aided by low-level upslope flow and eroding MLCINH. While weak large-scale ascent and marginal buoyancy limit confidence in storm coverage and longevity, around 50 kt of effective shear (characterized by a long/straight hodograph) will conditionally support splitting supercell structures. Isolated strong/severe gusts and marginally severe hail could accompany any persistent/organized storms that develop over southeastern WY, far northeastern CO, and the NE Panhandle through this evening. ..Weinman/Guyer.. 06/25/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BOU...CYS... LAT...LON 40630433 40820494 41400519 42070511 42370463 42330371 41590301 40890317 40630433 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 25 2023 Valid 252000Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PARTS OF THE MIDWEST/CENTRAL OH VALLEY TO THE MID/DEEP SOUTH... ...SUMMARY... Scattered to numerous severe storms are expected through tonight across a broad portion of the Midwest/Ohio Valley into the Mid and Deep South. The greatest threat for tornadoes, at least a couple of which could be strong, appears to be in central Indiana into western Ohio, and northern Kentucky vicinity through the early evening. ...Discussion... Only minor changes have been primarily due to the reduction of severe probabilities across the southwest Great Lakes. ..Smith.. 06/25/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sun Jun 25 2023/ ...Central Great Lakes/OH Valley to the Mid/Deep South... Shortwave trough over the Upper MS Valley will shift east into Lower MI tonight. Attendant surface cyclone will similarly track east from west-central WI into west-central Lower MI. Arcing cold front will have greater eastward advancement across parts of the Midwest, with trailing portion drifting south-southeast across the Mid-South. A broad swath of severe potential remains evident ahead of this front, likely yielding scattered areas of severe storms and embedded mesoscale corridors of more numerous reports. Ongoing convection persists across southeast KY into middle/eastern TN and will probably continue along the gradually eastward-shifting, north/south-oriented MLCAPE gradient. An isolated damaging wind threat should exist downstream across the southern Appalachians. A scattered wind/hail threat may emerge within multicell clusters that can regenerate westward later this afternoon over the TN Valley and persist into this evening. Potential for more numerous severe events appears to be focused within two bimodal corridors along/ahead of the front. The first is in the vicinity of eastern IN/western OH/northern KY border. Scattered thunderstorms will increase during the next few hours in the Lake MI vicinity arcing south across IN and then southwest across the Lower OH Valley. In the wake of the morning convection in KY, trailing outflow appears to have finally stalled across western KY and far southwest IN. How far to the northeast recovery can occur in its wake is uncertain, but it is plausible that it may be able to reach the IN/OH/KY border area by late afternoon/early evening. With a plume of mid 70s surface dew points to the west of this outflow, large buoyancy with MLCAPE of 3000-3500 J/kg will become common. Despite gradual weakening of the strong mid-level jetlet attendant to the shortwave trough, the leading edge of 50+ kt 500-mb westerlies should overlay the Lower OH Valley portion of the front. This setup will likely yield the best CAPE/shear/SRH parameter space near the IN/OH/KY border area where a few intense supercells are expected, capable of producing strong tornadoes and destructive hail/wind. Quicker upscale growth into clusters/QLCS is expected with northern extent where deep-layer wind profiles will be less favorable for maintaining discrete supercell structures. This activity should eventually outpace/become pinched off from the large buoyancy plume emanating from the Lower OH Valley. A second area of potentially destructive hail and wind should emanate along the AR portion of the front. The 12Z LZK sounding had a very favorable thermodynamic profile with a mean-mixing ratio of 18 g/kg and mid-level lapse rates of 8-8.5 C/km. With 74-77 F surface dew points common to the south of the front, very large buoyancy of 3500-4000 J/kg will be prevalent by late afternoon. Scattered thunderstorms will develop across northern AR and quickly become supercells within the gradient of mid/upper west-northwesterly flow. This type of orientation semi-parallel to the front should support upscale growth during the evening. Most morning CAMs are consistent in suggesting an MCS will evolve southeast across the Lower MS Valley with an enhanced threat for damaging winds. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0133 PM CDT Sun Jun 25 2023 Valid 261200Z - 271200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF NORTHEAST ARIZONA INTO NORTHWEST NEW MEXICO... The forecast remains largely on track. Made relatively minor adjustments to account for new guidance and fuel information. There is some potential for very isolated dry thunderstorm activity in central New Mexico. Forecast soundings, however, will only be marginally supportive of lightning at best. It appears more probable that activity will produce virga and locally raise RH. ..Wendt.. 06/25/2023 .PREV DISCUSSION... /ISSUED 0202 AM CDT Sun Jun 25 2023/ ...Synopsis... Across the Southwest, mid-level ridging will begin to slide eastward under the influence of a broad trough over the southern Great Basin. Enhanced southwesterly flow will overspread portions of the Southwest Day2/Monday, bolstering surface winds atop a warm and very dry air mass. Elevated to critical fire-weather conditions appear likely over parts of AZ and NM Day2/Monday afternoon and evening. ...Southwest... As the broad upper trough begins to shift eastward Day2/Monday it will partially suppress the sub-tropical ridge centered over parts of the Southwest. This will allow enhanced mid-level flow of 40-50 kt to overspread parts of central and eastern AZ into western NM through the afternoon. A deep and well-mixed boundary layer, with RH of 5-10% from very warm temperatures, should intersect with the stronger flow aloft strengthening surface winds to 20-30 mph and higher gusts. Receptive fuels underlying the favorable meteorological conditions will allow for several hours of critical fire-weather conditions from eastern AZ into western NM Day2/Monday. ...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 1232 PM CDT Sun Jun 25 2023 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MID-ATLANTIC STATES... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS NEAR THE BLACK HILLS... ...SUMMARY... Scattered severe thunderstorms are likely across the Mid-Atlantic states Monday afternoon through the evening. Damaging gusts and large hail will be the primary hazards. ...Eastern U.S.... A mid-level low over the Great Lakes and an associated trough over the Appalachians will slowly move east during the period. Moderate to strong cyclonic flow will move through the base of the trough and overspread a destabilizing warm sector east of the Appalachians. In the low levels, an effective front will push east across the upper OH Valley and Appalachians during the day with this convectively aided boundary pushing east of much of the Mid-Atlantic coast by early Tuesday morning. Scattered showers/isolated thunderstorms are forecast to be ongoing Monday morning across PA moving into southern NY and weakening by midday. In wake of this activity, strong heating from PA (where cloud breaks permit) southward into the western Carolinas will result in a moderate to strongly unstable airmass by early afternoon (1500-3000 J/kg SBCAPE). Weak capping will likely erode as scattered to numerous thunderstorms develop during the afternoon from NC north into PA. Model guidance shows 25-40 kt 500-mb flow over the Mid-Atlantic states which will aid in storm organization. Forecast hodographs shows backing of flow with height in the mid- to upper levels and will promote a fairly quick transition from a mix of cells and linear segments to a more extensive band of storms. The extensive coverage of the expected squall line and the quality of the mesoscale environment prompted an expansion in the 30-percent wind probabilities. Some model guidance shows slight low-level hodograph enlargement from parts of northeast PA into the lower Hudson Valley during the late afternoon/early evening. However, considerable uncertainty in the quality of the airmass precludes higher tornado probabilities across this region. By early to mid evening, much of the thunderstorm activity will push east of the coast across the Mid-Atlantic states with the remaining risk likely becoming more focused across NC. Farther south, more isolated storm coverage is expected over the northeast Gulf Coast with widely scattered storms expected over SC. Damaging gusts and perhaps large hail will be possible with the stronger storms. ...Northern WY into SD and northern NE... An upper-level ridge is forecast to move across the central and northern High Plains on Monday. Beneath the ridge, a narrow corridor of moderate instability is forecast to develop by afternoon. An easterly component to the low-level flow will facilitate 50s deg F dewpoints into northeast WY and western SD. Forecast soundings show steep lapse rates (7.5 deg C/km in the 700-500 mb layer) and elongated hodographs. The latest CAM solutions show widely scattered thunderstorms developing by early evening over northeast WY with some of this activity developing/moving east-southeast into southwest SD/northern NE by late evening into the overnight. Large hail/severe gusts are the primary hazards. ....Southeast OK/southern AR... Weak warm-air advection is forecast Monday night near a residual frontal zone forecast to be draped across southern AR into eastern OK. Isolated thunderstorms are possible within a very moist and conditionally unstable airmass will be in place with MUCAPE around 3000 J/kg. Strong mid to high-level northwesterly flow cresting the mid-level ridge will support storm-top venting and perhaps a localized large-hail risk. ..Smith.. 06/25/2023 Read more

MD 1244 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF SOUTHERN/EASTERN MN AND EXTREME WESTERN WI
Mesoscale Discussion 1244 NWS Storm Prediction Center Norman OK 0350 PM CDT Sat Jun 24 2023 Areas affected...Portions of southern/eastern MN and extreme western WI Concerning...Severe potential...Watch possible Valid 242050Z - 242245Z Probability of Watch Issuance...40 percent SUMMARY...An isolated severe threat may persist this afternoon. Watch issuance is possible. DISCUSSION...A supercell has recently developed across south-central MN, in a modest low-level warm advection regime in advance of an ejecting upper trough/low over the northern Plains. This thunderstorm has had a recent report of a funnel cloud. The eastern extent of any appreciable severe threat across southeastern MN will likely be constrained by a less unstable airmass into western WI. Even so, some threat for severe thunderstorms will probably persist this afternoon across parts of southern into eastern MN, as a weakly unstable airmass and 30-35 kt of deep-layer shear support some updraft rotation. Uncertainty regarding the overall magnitude of the severe threat remains high, but isolated large hail and damaging winds may occur with the more intense convection, especially if they can maintain supercellular structure. The tornado threat appears a bit lower due to marginal low-level shear. But, there may still be enough 0-1 km SRH to support a brief tornado. Observational trends will be closely monitored for possible watch issuance over the next couple of hours. ..Gleason/Grams.. 06/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ARX...MPX... LAT...LON 43879430 45029375 45269313 44929251 44469254 43679289 43549367 43649419 43879430 Read more

WW 0370 Status Updates
STATUS REPORT ON WW 370 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SW LWD TO 5 NE FRM. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1243 ..WENDT..06/24/23 ATTN...WFO...DMX...DVN...ARX... STATUS REPORT FOR WT 370 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC007-011-013-015-017-019-023-033-037-039-049-051-053-065-067- 069-075-079-081-083-089-091-095-099-101-103-107-109-113-117-121- 123-125-127-131-135-153-157-169-171-177-179-181-183-185-187-189- 191-195-197-242140- IA . IOWA COUNTIES INCLUDED ARE APPANOOSE BENTON BLACK HAWK BOONE BREMER BUCHANAN BUTLER CERRO GORDO CHICKASAW CLARKE DALLAS DAVIS DECATUR FAYETTE FLOYD FRANKLIN GRUNDY HAMILTON HANCOCK HARDIN HOWARD HUMBOLDT IOWA JASPER JEFFERSON JOHNSON KEOKUK KOSSUTH LINN LUCAS MADISON MAHASKA MARION MARSHALL MITCHELL MONROE POLK POWESHIEK STORY TAMA VAN BUREN WAPELLO WARREN WASHINGTON WAYNE Read more

WW 370 TORNADO IA 241835Z - 250000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 370 NWS Storm Prediction Center Norman OK 135 PM CDT Sat Jun 24 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central to eastern Iowa * Effective this Saturday afternoon and evening from 135 PM until 700 PM CDT. * Primary threats include... A couple tornadoes possible Scattered large hail and isolated very large hail events to 2.5 inches in diameter likely Scattered damaging wind gusts to 70 mph possible SUMMARY...A few supercells should develop across central Iowa and spread into eastern Iowa later this afternoon. Wind profiles will be most favorable for large hail and tornadoes through late afternoon. The tornado watch area is approximately along and 60 statute miles east and west of a line from 25 miles north northeast of Mason City IA to 45 miles southwest of Ottumwa IA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24030. ...Grams Read more

WW 0371 Status Updates
STATUS FOR WATCH 0371 HAS NOT BEEN ISSUED YET Read more

WW 371 TORNADO MN ND 242040Z - 250000Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 371 NWS Storm Prediction Center Norman OK 340 PM CDT Sat Jun 24 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northwest to west-central Minnesota Southeast North Dakota * Effective this Saturday afternoon and evening from 340 PM until 700 PM CDT. * Primary threats include... A couple tornadoes possible SUMMARY...A few low-topped supercells may persist through early evening with a continued threat for brief tornadoes. The tornado watch area is approximately along and 55 statute miles north and south of a line from 25 miles west of Fargo ND to 20 miles south of Bemidji MN. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). 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 370... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 50 knots. A few cumulonimbi with maximum tops to 350. Mean storm motion vector 16020. ...Grams Read more

MD 1243 CONCERNING TORNADO WATCH 370... FOR PARTS OF CENTRAL AND EASTERN IOWA
Mesoscale Discussion 1243 NWS Storm Prediction Center Norman OK 0339 PM CDT Sat Jun 24 2023 Areas affected...Parts of central and eastern Iowa Concerning...Tornado Watch 370... Valid 242039Z - 242245Z The severe weather threat for Tornado Watch 370 continues. SUMMARY...The threat for large hail, tornadoes, and damaging winds will continue this afternoon. The main risk will be in parts of southeastern Iowa in the next 1-2 hours. DISCUSSION...Winds in southwestern Iowa have veered to southwesterly. This trend continues to expand into parts of central Iowa as well. Where this has occurred, the tornado threat has decreased. Convection continues into northeast Iowa this afternoon. However, anvil debris and only partially modified outflow have kept buoyancy less than in southern/southeastern Iowa. Large hail and a brief tornado remain possible with the strongest storms. The primary area of tornado risk for the next 1-2 hours will likely exist with storms in south-central/southeastern Iowa. Here, buoyancy, storm mode, and low-level shear remain favorable. As storms progress farther into eastern Iowa, they will encounter decreasing moisture and increasing temperatures. While the tornado threat will decrease with eastward extent, large hail and damaging winds could still occur. ..Wendt.. 06/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DVN...ARX...DMX... LAT...LON 40899301 41559347 42879361 43329320 43449221 43239181 42519169 41399186 41089188 40879243 40899301 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0312 PM CDT Sat Jun 24 2023 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE MID-ATLANTIC STATES AND CAROLINAS... AMENDED FOR EXPANSION/UPGRADING OF SEVERE PROBABILITIES IN THE MID-ATLANTIC AND SOUTHEAST ...SUMMARY... A severe threat is expected to develop on Monday from the Carolinas into the Mid-Atlantic, where damaging winds and hail will be possible. An isolated severe threat will also be possible in the northern High Plains. ...Amended discussion for the Eastern U.S.... A mid to upper-level low will meander slowly eastward over the central Great Lakes during the period. An associated trough initially over the OH Valley/southern Appalachians is forecast to gradually shift eastward into the central Appalachians/Carolinas. A belt of moderate southwesterly 500-mb flow (25-40 kt) will overspread a destabilizing warm sector ahead of a front/composite outflow over the Appalachians. Strong heating ahead of the front and very moist low levels (66-74 deg F surface dewpoints) will likely result in a moderate to very unstable airmass from the Southeast northward into the Mid-Atlantic states. Several linear clusters of intensifying thunderstorms are forecast to develop by early afternoon in the immediate lee of the higher terrain. Further upscale growth into a more expansive band of linear segments is expected by late afternoon/early evening from the Mid-Atlantic states southward into the Carolinas. Damaging gusts appear to be the primary hazard due to 50-70 mph gusts. Isolated large hail may accompany the stronger cores. Have added 5-percent severe probabilities across the northeast Gulf Coast for the possibility of 1) at least isolated strong/severe thunderstorms pushing off the coast during the morning, and 2) diurnal storms rejuvenating on the composite outflow/front as it may provide a focus for additional storms. ---Previous Discussion--- ...Eastern U.S... An upper-level low is forecast to move through the Great Lakes region on Monday, as an associated trough moves into the southern Appalachians. At the surface, a front will move into the Appalachians as a pre-frontal trough develops from the Carolinas into the Mid-Atlantic. Moderate to strong instability is expected by afternoon along and near the surface trough. Convection will initiate in the higher terrain of the Appalachians and spread eastward into the Piedmont. It appears that an isolated severe threat will develop with storms that move into the stronger instability during the late afternoon from eastern Pennsylvania southward into the Carolinas. The greatest severe threat could be from southern Virginia into central North Carolina, where model forecasts suggest the combination of instability and shear will be maximized. Storms that form in this more favorable zone could have a threat for wind damage and hail, mainly during the late afternoon and early evening. ...Northern High Plains... An upper-level ridge will remain over the High Plains on Monday. At the surface, a narrow corridor of maximized low-level moisture is forecast across the central and northern High Plains. As instability increases during the day, isolated to scattered thunderstorms will likely develop. The strongest storms may form from eastern Wyoming southeastward into western Nebraska, along and near the instability axis. NAM forecast soundings by late afternoon near Scottsbluff, Nebraska have MLCAPE near 1500 J/kg and 0-6 km shear of 50 to 60 knots. This, combined with 700-500 mb lapse rates approaching 8 C/km should be sufficient for an isolated severe threat. The large temperature-dewpoint spreads are expected to result in high storm bases. The storms could be associated with strong wind gusts and hail. ..Smith.. 06/24/2023 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0302 PM CDT Sat Jun 24 2023 Valid 242000Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE UPPER MIDWEST TO THE MID-MS VALLEY... ...SUMMARY... Scattered severe thunderstorms are forecast across portions of Minnesota and Iowa into the Mid-Mississippi Valley through this evening. A couple of tornadoes, large hail, and damaging winds are all possible. ...20Z Update... The outlook generally remains on track, and only minor adjustments were made with this update. In particular, the Slight risk in Iowa was expanded slightly westward into far northwest Iowa to account for potential redevelopment of an isolated supercell or two this evening, which would pose a risk of large hail. Elsewhere, only minor modifications were made based on the latest observations. For details, see the previous discussion, along with WW370. ..Weinman/Grams.. 06/24/2023 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Jun 24 2023/ ...Upper Midwest to Mid-MS Valley... Remnants of a decaying MCS persist in eastern IA with residual cloud cover and convective redevelopment in its wake across central into southwest IA. More pronounced insolation has occurred over northwest IA and parts of eastern NE. This will likely yield a moderately unstable air mass with MLCAPE approaching 2500 J/kg in a few hours. Morning guidance is insistent on surface-based thunderstorm development occurring by early afternoon, which appears a bit too soon given the lingering morning convection/cloudiness, but is plausible owing to modest mid-level lapse rates/EML. As such, confidence is below-average with regard to timing and evolution of this afternoon's severe threat. Downstream of a 60-65 kt 500-mb westerly jetlet centered on NE, deep-layer shear will support potential for several supercells. A few-hour window for a couple of these to produce tornadoes may overlap along the residual outflow boundary before convection likely consolidates into clusters and low-level winds become more veered into the evening. East to southeast-moving clusters may develop into a semi-organized MCS during the evening and yield a strong to isolated severe wind threat across the Mid-MS Valley. This activity should gradually weaken tonight after eventually outpacing greater instability/buoyancy to its west. A separate area of lower-topped tornado potential is evident in northwest/north-central MN along the surface warm front that will extend east of the primary cyclone centered near the northeast SD/southeast ND border area. Backed surface winds that veer with height will support enlarged low-level hodograph curvature. In conjunction with low LCLs, these factors may support a threat for brief tornadoes during the late afternoon to early evening. ...West TX to the Ozark Plateau... Isolated to scattered high-based thunderstorms will develop during the late afternoon to early evening across at least west TX, and perhaps across parts of OK this evening into tonight. With a stout mid-level anticyclone centered along the Trans-Pecos portion of the Rio Grande, deep-layer shear will be progressively stronger with northeast extent towards the Ozark Plateau. Sporadic severe gusts from microbursts will be the main threat in TX, with a conditional threat for isolated severe wind/hail into the Ozark Plateau. ...LA vicinity... Despite weak low-level shear, a belt of modest mid-level northerlies will support potential for an isolated severe wind and hail threat as isolated to scattered thunderstorms develop this afternoon within the boundary-layer moisture/buoyancy gradient between LA/MS. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0149 PM CDT Sat Jun 24 2023 Valid 251200Z - 261200Z The previous forecast remains on track. ... Eastern Arizona and Western New Mexico ... A critically dry airmass will remain in place on Sunday. Deep mixing during the afternoon will result in near critical wind speeds (20 mph) across portions of this area. However, at this time, the greatest confidence in achieving critical wind speeds will be over less receptive fuels than other areas. As such, have not introduced a critical delineation, but will reevaluate with subsequent forecasts. ..Marsh.. 06/24/2023 .PREV DISCUSSION... /ISSUED 0159 AM CDT Sat Jun 24 2023/ ...Synopsis... A broad mid-level trough is forecast to shift eastward and impinge on the enhanced sub-tropical ridge over portions of the Southwest Day2/Sunday. While height gradients aloft will increase in response to the approaching trough, the stronger flow aloft should remain displaced to the west of the driest air mass. Still, some enhancement of surface winds is expected over eastern AZ and western NM, with model soundings showing boundary-layer winds of 15-20 mph likely through the day. Deep mixing, and another day of warm temperatures, will also support low afternoon RH values in the single digits to teens. Favorable meteorological conditions for elevated to locally critical fire-weather conditions are expected through much of the day over portions of western NM where fuels remain quite dry. Less confidence in receptive fuels exists farther west into AZ. However, a few hours of elevated fire-weather conditions are also possible given the dry and breezy conditions expected. ...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 1239 PM CDT Sat Jun 24 2023 Valid 251200Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MIDDLE TENNESSEE...CENTRAL AND EASTERN KENTUCKY...SOUTHWEST OHIO... ...SUMMARY... Scattered severe thunderstorms are likely from the Ohio Valley and potentially southwestward into the Mid South and into Mississippi and Alabama. Severe gusts resulting in wind damage and large to very large hail will be possible on Sunday. A couple of tornadoes are possible in the Ohio Valley. ...OH Valley into the Mid South and MS/AL... A mid-level low/associated trough over the upper to mid MS Valley will move east-southeast into the central Great Lakes by early Monday morning. A belt of strong 500-mb flow will move through the base of the trough over the mid MS Valley into the OH Valley and portions of the TN Valley. Large model variability is resulting in considerable uncertainty for this forecast with ongoing showers/thunderstorms expected Sunday morning from potentially the southwestern Great Lakes southward into the Mid South. With those caveats/concerns mentioned, a large reservoir of rich low-level moisture will reside from the lower MS Valley northward into the OH Valley in absence of any convective overturning during the morning. More aggressive model solutions for destabilization show the development of a very unstable to extremely unstable airmass developing from AR eastward through the Mid South and northward into the OH Valley. It seems likely some of this broad region will have a thunderstorm cluster with associated wind/hail risk deplete some of the potential instability. However, areas located on the periphery of the potential thunderstorm clusters/MCSs near residual outflow or on the front, will be favored areas for additional thunderstorms and a severe risk. It seems most probable that a concentrated area of wind-damage potential may reside over parts of the OH Valley southward into middle TN where the mid-level speed max is forecast to overspread the warm sector. Have aggressively expanded 5 and 15-percent wind probabilities into the upper OH Valley, MS/AL and into AR to account for both spatial uncertainty and the depiction by the last 6 model runs of the deterministic ECMWF and the latest HREF ensemble sshow several linear clusters moving across these corridors. By the mid evening, a gradual subsiding and confining of the severe risk is expected with the greatest risk perhaps shifting into parts of the lower MS Valley. ...Southeast WY... Strong heating amidst a weak upslope regime may foster a few thunderstorms during the afternoon over southeast WY near the Cheyenne Ridge. Strong mid- to high-level westerly flow strengthening with height will favor some organization with the stronger updrafts. An isolated risk for hail/wind may accompany the stronger cores for a few hours during the late afternoon/early evening before this activity subsides. ...Western ID and eastern OR... A mid-level low over the interior Pacific NW and strong heating will promote scattered thunderstorms developing during the day across the interior NW and northern Intermountain regions. Very steep low to mid-level lapse rates and adequate moisture will probably result in around 500 J/kg MLCAPE. Severe gusts with the stronger downdrafts may occur with the more robust convection during the late afternoon into the mid evening hours. ..Smith.. 06/24/2023 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook AMEND 1 NWS Storm Prediction Center Norman OK 0457 PM CDT Fri Jun 23 2023 Valid 232000Z - 241200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTH-CENTRAL HIGH PLAINS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN PLAINS... AMENDED FOR INCREASING SEVERE PROBABILITIES OVER PARTS OF NORTH TEXAS ...SUMMARY... Scattered severe thunderstorms, capable of producing large hail and strong/damaging wind gusts and a tornado or two, are expected across the North-central High Plains, with other severe storms across the southern Plains today and tonight. ...Amended discussion... Have increased hail/wind probabilities over parts of north TX due to the ongoing/developing severe clusters to the north and southeast of the greater DFW Metroplex vicinity. ...Discussion... Only a few minor modifications of the previous outlook. 1) Added 2-percent tornado probabilities from northeast CO southward through CO/KS into the TX Panhandle. 2) Enlarged the significant hail area over the southern High Plains. 3) Adjusted the Enhanced Risk (30-percent hail) westward to the ongoing severe thunderstorm activity over central WY. 4) Spatial enlarging of the 5-percent wind probabilities over eastern OK. ..Smith.. 06/23/2023 .PREV DISCUSSION... /ISSUED 1156 AM CDT Fri Jun 23 2023/ ...North-central Plains... No changes for this region aside from Marginal-related spatial adjustments across Wyoming. The most concentrated, well-organized severe threat still appears to be over parts of the High Plains from southeastern Montana to western Nebraska this afternoon and evening. Scattered thunderstorms should evolve upscale from initial multicell and supercell development near the Bighorn and Laramie Ranges, with an early multimodal threat transitioning toward severe wind (locally 65+ kt gusts possible) with time this evening and overnight. A relatively narrow corridor of favorable airmass heating, warm-advection-related recovery, and upslope flow into higher terrain will support afternoon/evening severe potential. Activity should develop over and near the Wyoming ranges this afternoon as strengthening large-scale ascent and deep-layer shear spread over the region ahead of the ejecting shortwave trough, conterminous with favorably, diabatically minimized MLCINH. Initial mixed-mode convection will offer all severe hazards, with tornadoes and significant hail being a threat from any sustained supercell(s). Steep low/middle-level lapse rates and favorable boundary-layer moisture will contribute to peak/preconvective MLCAPE ranging from near 3000 J/kg over the northeastern Colorado/southwestern Nebraska to 1000-2000 J/kg in a small part of northeastern Wyoming and southeastern Montana. Lengthening and well-curved hodographs are forecast to develop as low-level cyclogenesis proceeds, in support of the hail/tornado threat. One or two MCSs should evolve this evening, accessing theta-e advection and moisture transport related to a 40-45 kt LLJ, with aggregation of cold pools rendering an increasingly widespread threat for damaging and severe gusts. The severe risk should continue eastward across Nebraska/South Dakota much of the night. ...Southern Plains including West/North Texas and Oklahoma... A cluster of strong/severe storms is ongoing across west-central Oklahoma at late morning. These storms continue to exhibit upscale-growing trends aside from a morning history of isolated severe-caliber wind gusts. The potential for wind damage and isolated hail may persist east-southeastward across southern/central Oklahoma and nearby north Texas this afternoon. Otherwise, farther west, widely scattered thunderstorms are expected to redevelop by mid/late afternoon near the dryline/lee trough across far west/northwest Texas including the Texas South Plains. These initially high-based storms will progress eastward, with some of these storms potentially interacting with the outflow-reinforced baroclinic zone via the early day storms. Storms will gradually encounter greater low-level moisture as they move eastward, with surface dewpoints into the 60s and lower 70s F, with 2500-3500 J/kg MLCAPE near and east of the Caprock. Though near-surface flow will be modest, strong veering with height will enable enough deep-layer shear (effective values around 35-40 kt) for a blend of early multicell and supercell modes, offering both large hail and severe-caliber wind gusts. A gradual coalescence of cold pools from multiple storms is probable, with a severe risk probably continuing eastward this evening into the overnight across north Texas and possibly southern Oklahoma. ...Eastern Colorado/western Kansas... Severe risk adjustments have been made across the region given trends in short-term observations/guidance. Concern exists for a viable potential for intense storm development, even if somewhat isolated, by mid/late afternoon, within a supercell-favorable environment including steep lapse rates, strong buoyancy and 40+ kt effective shear. ...Mid-Atlantic States/Delmarva... Ahead of the upper low centered over Ohio/Lower Great Lakes, a moist environment with moderately enhanced low-level southerly winds may support a few stronger/locally severe storms this afternoon across the region. Read more

WW 0364 Status Updates
STATUS FOR WATCH 0364 HAS NOT BEEN ISSUED YET Read more

WW 364 SEVERE TSTM TX 232155Z - 240300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 364 NWS Storm Prediction Center Norman OK 455 PM CDT Fri Jun 23 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of North central into east central Texas * Effective this Friday afternoon and evening from 455 PM until 1000 PM CDT. * Primary threats include... Scattered damaging wind gusts to 70 mph possible Isolated very large hail events to 2 inches in diameter possible SUMMARY...Clusters of storms, including embedded supercells, are expected to persist while spreading southward through the evening. The more intense storms will be capable of producing damaging gusts of 60-70 mph and isolated large hail of 1-2 inches in diameter. The severe thunderstorm watch area is approximately along and 35 statute miles east and west of a line from 25 miles north northeast of Dallas TX to 50 miles southeast of Corsicana TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 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 362...WW 363... 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 600. Mean storm motion vector 35025. ...Thompson Read more

MD 1223 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF CENTRAL AND SOUTHERN FLORIDA
Mesoscale Discussion 1223 NWS Storm Prediction Center Norman OK 0429 PM CDT Fri Jun 23 2023 Areas affected...Parts of central and southern Florida Concerning...Severe potential...Watch unlikely Valid 232129Z - 232330Z Probability of Watch Issuance...5 percent SUMMARY...A couple loosely organized storms capable of wind damage and marginal hail are possible this afternoon. DISCUSSION...Isolated to widely scattered thunderstorms are ongoing across parts of central and southern Florida this afternoon, generally focused along a southwest/northeast-oriented confluence band and sea breeze boundaries. Given continued diurnal destabilization of a moist air mass (lower/middle 70s dewpoints) beneath steeper-than-average midlevel lapse rates, storms could continue to strengthen through the afternoon. And, 30 kt of midlevel flow (sampled by the MLB VWP) could aid in some updraft organization. As storms generally spread northeastward toward the coast, locally damaging gusts and marginal hail could accompany any loosely organized clusters this afternoon. The threat should generally remain localized and marginal. ..Weinman/Thompson.. 06/23/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MFL...MLB...TBW... LAT...LON 26928046 26528072 26228109 26348162 27208166 27638169 28268178 28768136 28758070 28158040 27408025 26928046 Read more