SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Sat Aug 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FROM THE MID-ATLANTIC INTO NORTH CAROLINA...AND ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Thunderstorms, associated with a marginal severe threat, will be possible on Monday in parts of the Mid-Atlantic, North Carolina, and from the central to the northern High Plains. ...Mid-Atlantic/North Carolina... An upper-level trough will move slowly eastward across the southern and central Appalachians on Monday, as a cold front advances southeastward toward the middle Atlantic Coast. Surface dewpoints across most of the Mid-Atlantic into North Carolina are forecast to be in the 60s F, with 70+ surface dewpoints confined to the immediate Atlantic coast. As surface temperatures warm, a pocket of instability will likely develop near and ahead of the front, and in the post-frontal airmass. Scattered thunderstorms are expected to form within these areas as surface temperatures warm during the day. Although low-level lapse rates will become steep in many areas by afternoon, deep-layer shear is forecast to remain relatively weak. The instability could still be strong enough for a marginal severe threat. Isolated strong to severe wind gusts could occur near and around peak heating. ...Central to Northern High Plains... An upper-level ridge is forecast to move across the Central High Plains and northern Plains on Monday. An axis of instability will likely develop during the day to the west of the ridge, from eastern Colorado northward into eastern Montana and western North Dakota. Although large-scale ascent will be weak along this corridor, thunderstorms are expected to form in some areas due to topographical forcing in the central and northern Rockies. More isolated storms will be possible in the lower elevations of the central and northern High Plains. Forecast soundings across the central and northern High Plains have steep low to mid-level lapse rates and sufficient deep-layer shear for a marginal severe threat. Relatively large surface temperature-dewpoint spreads could enhance downdrafts associated with high-based storms. Hail could also accompany the stronger cells, especially further west near the higher terrain. ...Ark-La-Tex... North-northwesterly mid-level flow will be in place across the Ark-La-Tex on Monday. At the surface, a quasi-stationary front is forecast from northeast Texas into Louisiana, where surface dewpoints should be in the lower 70s F. As surface temperatures warm during the day, low-level lapse rates will become steep. This combined with moderate deep-layer shear may support an isolated severe threat. Although there is some uncertainty concerning convective coverage, the forecast environment should be enough for a few marginally severe storms. ..Broyles.. 08/17/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0153 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...Synopsis... A mid-level trough will continue to meander along the West Coast while upper ridging persists across the central U.S. tomorrow (Sunday). A 500 mb speed max within the upper trough should progress northward toward the Pacific Northwest and International border, with a gradual weakening in isallobaric flow expected to the lee of the Cascades and Sierra. Nonetheless, boundary-layer mixing will promote Elevated dry and breezy conditions in terrain-favoring locations east of the Sierra into the Great Basin by afternoon, where Elevated highlights have been introduced. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHEASTERN OREGON... ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHWESTERN NEVADA... ...Synopsis... A mid-level trough will impinge on the West Coast as upper ridging amplifies over the Rockies into the Plains today. Surface cyclone development is likely to the lee of the Cascades by afternoon, promoting ample buoyancy, lift, and shear for thunderstorms, some of which may be strong. Otherwise, strong downslope and isallobaric flow across the western Great Basin ahead of the upper trough/surface low will promote widespread dry and breezy conditions capable of supporting wildfire spread. ...Along and to the lee of the Cascades - Thunderstorms... By late afternoon, multiple strong thunderstorms should develop amid strong flow aloft. Some of the storms may be high-based, with a couple of dry strikes possible. Of greater concern is the potential for erratic and strong to possibly severe gusts, which may exacerbate ongoing fire concerns, as well as with ignitions from strikes accompanying the storms. Given receptive fuels, isolated dry thunderstorm highlights have been maintained. ...Harney Basin and western Great Basin - Dry/Windy Conditions... By afternoon peak heating, RH is expected to drop into the 15-20 percent range as the boundary layer mixes. When also considering the contribution of isallobaric flow, winds may sustain above 20 mph, particularly over portions of the Harney Basin and in southwestern Nevada, where Critical highlights have been maintained. Otherwise, Elevated highlights remain over a broader area where dry and breezy conditions are expected to overlap with dry fuel beds. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sat Aug 17 2024 Valid 181200Z - 191200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CAROLINAS AND SOUTHEAST... ...SUMMARY... Scattered strong thunderstorms, associated with a severe threat, will be possible on Sunday from the Mid-Atlantic and Carolinas westward into the Southeast, and in parts of the central and northern Plains. ...Mid-Atlantic/Carolinas/Southeast An upper-level trough will move across the Ohio Valley and southern Appalachians on Sunday. At the surface, an associated cold front will approach the Mid Atlantic Seaboard, and move into the Southeast. Ahead of the front, surface dewpoints in the lower to mid 70s F, will contribute to the development of moderate instability by midday. As surface temperatures warm, thunderstorms are expected to form in the higher terrain of the southern and central Appalachians. Additional storms appear likely to develop further to the east near the front and across the moist sector ahead of the front. Current model forecasts suggest that a pocket of moderate instability, with MLCAPE potentially above 2000 J/kg, may develop in parts of the Carolinas. Forecast soundings across eastern North Carolina around 21Z show some directional shear below 850 mb, with speed shear in the mid-levels, resulting in 0-6 km shear in the 25 to 35 knot range. In addition, lapse rates are forecast to become steep, with 0-3 km lapse rates peaking near 8 C/km in the mid afternoon. This should be favorable for an isolated severe threat. The wind profile will favor multicells with isolated wind-damage potential. ...Ozarks/Lower Mississippi Valley... Northwest mid-level flow will be in place on Sunday across the lower to mid Mississippi and Tennessee Valleys. A front is forecast to move southward across the Lower Mississippi Valley and central Gulf Coast States. To the south of the front, surface dewpoints in the lower to mid 70s F will contribute to the development of moderate to strong instability. As low-level convergence increases along and ahead of the front, thunderstorms are expected to form in the early to mid afternoon. Storms will likely expand in coverage, moving southeastward across the Lower Mississippi Valley during the late afternoon. Forecast soundings at 21Z from southern Arkansas southeastward into central Mississippi have MLCAPE reaching the 2500 to 3500 J/kg range, and show 0-6 km shear in the 30 to 35 knot range. 0-3 km lapse-rates are forecast to peak near 8 C/km during the afternoon. This will be favorable for an isolated severe threat, with isolated supercells possible. However, multicell may be the prevalent storm mode. Rotating storms will have potential for isolated large hail. Severe wind gusts will be possible with any cell that can become organized. ...Central and Northern High Plains... An upper-level ridge will be in place on Sunday from the central Rockies into the northern High Plains. An axis of instability is forecast to develop to the east of the ridge from western Kansas north-northwestward into eastern Montana. Although large-scale ascent will be weak, isolated thunderstorms may form as temperatures warm during the day. Model forecasts Sunday afternoon along and near the instability axis have surface dewpoints around 60 F, steep low to mid-level lapse rates, and relatively large surface-dewpoint temperature spreads. This would be favorable for strong outflow gusts with isolated high-based storms in areas with sufficient instability. Hail will also be possible, mainly within rotating cells that come out of higher terrain, where the steepest mid-level lapse rates are forecast. ..Broyles.. 08/17/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CDT Sat Aug 17 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE OHIO VALLEY/KY...UTAH REGION...AND PARTS OF WESTERN OREGON/SOUTHWEST WASHINGTON... ...SUMMARY... Scattered severe thunderstorms are possible in parts of Kentucky and the Ohio Valley on Saturday afternoon. Isolated severe thunderstorms are also expected across the Utah region and over parts of western Oregon into southwest Washington. Wind and hail are the primary threats. ...Ohio Valley/KY... Great Lakes/Midwest trough will progress east today and extend from Lower MI-KY by 18/00z. High-level diffluent flow will be noted across the OH Valley into the Mid South which will prove favorable for scattered robust convection, especially by early afternoon as the boundary layer destabilizes with daytime heating. Strength of this feature will encourage a notable synoptic front to advance into OH/western KY by late afternoon, coincident with favorable upper diffluence. Latest model guidance suggests a considerable amount of convection will likely evolve along/ahead the wind shift, concentrated within a zone of stronger instability -- KY/southern OH. While some supercell potential does exist across this region, the majority of storms will likely be multicellular with clusters common. Wind/hail are expected with this activity. ...Utah Region... Well-defined mid-level short-wave trough is lifting north across the lower CO River Valley late this evening. With the upper ridge holding across the southern Rockies, this feature will progress across UT early in the period before shifting into eastern ID/southwest WY by late afternoon. Latest HREF model guidance actually reflects this short wave well with all members exhibiting substantial convection near the mid-level vort over southeast NV at sunrise. This activity will spread/develop northeast across UT during the day within a strongly sheared environment. Though, lapse rates will be seasonally weak given the convective coverage and cloud cover. Even so, robust organized updrafts are expected and wind should be the primary threat with these storms. ...Western OR/Southwest WA... Strong 500mb speed max will round the base of the offshore trough and translate across northern CA into eastern OR by early evening. Left exit region of this feature will aid UVV near the higher terrain and cooling/moistening mid-levels will contribute to modest buoyancy along the cyclonic side of the speed max. Forecast soundings exhibit strongly sheared profiles and isolated supercells are expected to develop, then spread north-northeast as a short-wave trough ejects into southern WA. Hail/wind are possible with these storms. ..Darrow/Squitieri.. 08/17/2024 Read more

MD 1928 CONCERNING SEVERE THUNDERSTORM WATCH 629... FOR PORTIONS OF EXTREME EASTERN OKLAHOMA INTO CENTRAL ARKANSAS
Mesoscale Discussion 1928 NWS Storm Prediction Center Norman OK 1123 PM CDT Fri Aug 16 2024 Areas affected...portions of extreme eastern Oklahoma into central Arkansas Concerning...Severe Thunderstorm Watch 629... Valid 170423Z - 170600Z The severe weather threat for Severe Thunderstorm Watch 629 continues. SUMMARY...The severe threat continues across Severe Thunderstorm Watch 629. Damaging gusts remain the main threat with these storms over the next few hours. DISCUSSION...An MCS has materialized from congealing storms over the last few hours, with strong wind gusts over 50 mph recently reported. Preceding the eastern portion of the MCS is a cooler airmass, characterized by surface temperatures in the upper 70s to low 80s F. However, along the western periphery of the MCS track are warmer surface temperatures between 85-90 F, which also reside beneath the eastern periphery of a modest LLJ and accompanying WAA. As such, the portion of the MCS cold pool propagating into this airmass has the greatest chance for supporting stronger updrafts and corresponding downdrafts, which may penetrate the increasing MLCINH. Here, a few additional strong to severe gusts may occur over the next few hours. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...TSA... LAT...LON 35609511 36009344 36019253 35739224 35359230 35039274 34799328 34689389 34629436 34649475 34829518 35609511 Read more

MD 1925 CONCERNING SEVERE THUNDERSTORM WATCH 628... FOR PORTIONS OF WESTERN OKLAHOMA INTO FAR NORTHWESTERN ARKANSAS
Mesoscale Discussion 1925 NWS Storm Prediction Center Norman OK 0738 PM CDT Fri Aug 16 2024 Areas affected...Portions of western Oklahoma into far northwestern Arkansas Concerning...Severe Thunderstorm Watch 628... Valid 170038Z - 170215Z The severe weather threat for Severe Thunderstorm Watch 628 continues. SUMMARY...The severe threat continues across Severe Thunderstorm Watch 628. Severe wind and hail remain the primary threats over the next few hours. DISCUSSION...A robust uptick in convective coverage and intensity has been noted in north-central Oklahoma to southeast Kansas over the past couple of hours, where severe wind and hail have been observed. Despite weak forcing, thunderstorms have managed to initiate off of multiple converging low-level baroclinic/outflow boundaries. Furthermore, the OUN 00Z observed sounding shows near 3000 J/kg MLCAPE atop a mixed boundary layer, characterized by 30F T/Td spreads. 20-30 F spreads are also evident across eastern OK ahead of the ongoing storms, with 00Z mesoanalysis depicting over 4500 J/kg MLCAPE (given mid 70s F surface dewpoints). Meanwhile, the 00Z OUN sounding, as well as VNX, TLX, and INX VAD profilers show hodographs with modest low-level curvature and mid-level elongation, supporting supercell structures when accounting for the strong to locally extreme buoyancy in place. As such, supercells may persist into northeast OK over the next few hours with a continued severe-wind threat, though large hail is also possible. ..Squitieri.. 08/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...TSA...ICT...OUN... LAT...LON 35209990 36199857 36849753 37039542 36979429 36659377 36289372 36029411 35869555 35629666 35099774 34889843 34939930 35209990 Read more

MD 1926 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF NORTHWESTERN ARKANSAS
Mesoscale Discussion 1926 NWS Storm Prediction Center Norman OK 0845 PM CDT Fri Aug 16 2024 Areas affected...portions of northwestern Arkansas Concerning...Severe potential...Watch likely Valid 170145Z - 170245Z Probability of Watch Issuance...95 percent SUMMARY...The severe threat is increasing across portions of northwestern AR. Severe gusts are the main threat, though a few instances of large hail are also possible. A WW will be needed soon to address the impending severe threat. DISCUSSION...A robust multicellular cluster (perhaps with embedded transient supercells) continues to rapidly propagate to the southeast. Multiple instances of 70-80 mph gusts and wind damage have been reported with this cluster, and MRMS MESH suggests that at least some marginally severe hail may be falling in the stronger storm cores. Preceding these storms is a thermodynamic airmass characterized by 2000-3000 J/kg MLCAPE amid only slowly increasing MLCINH. Effective bulk shear values are likely exceeding 30 kts per 00Z mesoanalysis, which is sufficient for continued storm organization and intensity given the aforementioned buoyancy. Though MLCINH should ultimately tame severe potential later tonight, at least some concentrated severe wind/hail threat may still materialize over the next couple of hours. A WW issuance will be needed soon to address the near-term severe threat. ..Squitieri/Edwards.. 08/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...TSA... LAT...LON 35459441 36189344 36449288 36229238 35719219 35369230 35039262 34929309 34939366 34999419 35459441 Read more

WW 0628 Status Updates
STATUS REPORT ON WW 628 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SE END TO 20 NE END TO 35 SSE ICT. ..SQUITIERI..08/17/24 ATTN...WFO...TSA...SGF...OUN... STATUS REPORT FOR WS 628 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-015-087-143-170340- AR . ARKANSAS COUNTIES INCLUDED ARE BENTON CARROLL MADISON WASHINGTON MOC009-119-145-170340- MO . MISSOURI COUNTIES INCLUDED ARE BARRY MCDONALD NEWTON OKC001-021-035-037-041-071-097-103-105-113-115-117-119-131-143- 145-147-170340- OK . OKLAHOMA COUNTIES INCLUDED ARE ADAIR CHEROKEE CRAIG CREEK DELAWARE KAY Read more

WW 0628 Status Updates
STATUS REPORT ON WW 628 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SE END TO 20 NE END TO 35 SSE ICT. ..SQUITIERI..08/17/24 ATTN...WFO...TSA...SGF...OUN... STATUS REPORT FOR WS 628 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-015-087-143-170340- AR . ARKANSAS COUNTIES INCLUDED ARE BENTON CARROLL MADISON WASHINGTON MOC009-119-145-170340- MO . MISSOURI COUNTIES INCLUDED ARE BARRY MCDONALD NEWTON OKC001-021-035-037-041-071-097-103-105-113-115-117-119-131-143- 145-147-170340- OK . OKLAHOMA COUNTIES INCLUDED ARE ADAIR CHEROKEE CRAIG CREEK DELAWARE KAY Read more

WW 628 SEVERE TSTM AR MO OK 162035Z - 170400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 628 NWS Storm Prediction Center Norman OK 335 PM CDT Fri Aug 16 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Northwest Arkansas Extreme southwest Missouri Northern Oklahoma * Effective this Friday afternoon and evening from 335 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 75 mph possible Scattered large hail likely with isolated very large hail events to 2.5 inches in diameter possible SUMMARY...Multiple areas of thunderstorm development are possible along and south of the Kansas/Oklahoma border through late evening, in a storm environment favoring organized clusters and supercells. The more intense storms will be capable of producing very large hail up to 2.5 inches in diameter, as well as severe outflow winds up to 75 mph. The severe thunderstorm watch area is approximately along and 35 statute miles north and south of a line from 40 miles west southwest of Alva OK to 30 miles south southeast of Monett MO. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 627... AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 600. Mean storm motion vector 30025. ...Thompson Read more

WW 0629 Status Updates
STATUS FOR WATCH 0629 HAS NOT BEEN ISSUED YET Read more

WW 0629 Status Updates
STATUS FOR WATCH 0629 HAS NOT BEEN ISSUED YET Read more

WW 629 SEVERE TSTM AR 170200Z - 170700Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 629 NWS Storm Prediction Center Norman OK 900 PM CDT Fri Aug 16 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of West-central to north-central Arkansas * Effective this Friday night and Saturday morning from 900 PM until 200 AM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Isolated very large hail events to 2 inches in diameter possible SUMMARY...A complex of severe thunderstorms -- with a history of severe as recently as a 56-kt gust at NW AR Regional (XNA) at 141Z -- is expected to pose a continuing severe-wind and hail threat southeastward into more of AR this evening. Some expansion or shift in motion toward southward also is possible. The severe thunderstorm watch area is approximately along and 40 statute miles north and south of a line from 10 miles south of Fort Smith AR to 55 miles northeast of Russellville AR. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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 628... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 600. Mean storm motion vector 32035. ...Edwards Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Fri Aug 16 2024 Valid 170100Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN PLAINS/SOUTHEAST KANSAS INTO NORTHERN ARKANSAS... ...SUMMARY... Scattered severe thunderstorms remain possible this evening across portions of the southern Plains/southeast Kansas into northwest Arkansas. Damaging gusts and hail are the primary threats. ...01z Update... Low-amplitude short-wave trough is currently evident in satellite imagery, extending from southeast KS-northeast TX Panhandle. This feature is digging southeast within mean northwesterly flow along the back side of the Great Lakes/OH Valley trough. Synoptic front that advanced into this region arcs across MO-southern KS-northern TX Panhandle. This boundary is serving as a focus for scattered robust convection, mostly concentrated across southeast KS/extreme northeast OK along the northern fringe of a most buoyant airmass. Surface temperatures remain in the 90s to near 100F south of the boundary across much of OK into the TX south Plains. 00z sounding from OUN exhibits MLCAPE on the order of 3000 J/kg with 30kt 0-6km bulk shear. Latest VWP data depicts 1km flow around 15kt across northeast OK, but models suggest LLJ will increase over the next several hours into northeast OK where values may exceed 30kt. This will favor a southeast-moving complex of storms into northern AR later this evening. Damaging gusts and hail remain the primary threats. ..Darrow.. 08/17/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Fri Aug 16 2024 Valid 170100Z - 171200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN PLAINS/SOUTHEAST KANSAS INTO NORTHERN ARKANSAS... ...SUMMARY... Scattered severe thunderstorms remain possible this evening across portions of the southern Plains/southeast Kansas into northwest Arkansas. Damaging gusts and hail are the primary threats. ...01z Update... Low-amplitude short-wave trough is currently evident in satellite imagery, extending from southeast KS-northeast TX Panhandle. This feature is digging southeast within mean northwesterly flow along the back side of the Great Lakes/OH Valley trough. Synoptic front that advanced into this region arcs across MO-southern KS-northern TX Panhandle. This boundary is serving as a focus for scattered robust convection, mostly concentrated across southeast KS/extreme northeast OK along the northern fringe of a most buoyant airmass. Surface temperatures remain in the 90s to near 100F south of the boundary across much of OK into the TX south Plains. 00z sounding from OUN exhibits MLCAPE on the order of 3000 J/kg with 30kt 0-6km bulk shear. Latest VWP data depicts 1km flow around 15kt across northeast OK, but models suggest LLJ will increase over the next several hours into northeast OK where values may exceed 30kt. This will favor a southeast-moving complex of storms into northern AR later this evening. Damaging gusts and hail remain the primary threats. ..Darrow.. 08/17/2024 Read more

MD 1923 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHEASTERN WISCONSIN AND NORTHERN ILLINOIS
Mesoscale Discussion 1923 NWS Storm Prediction Center Norman OK 0531 PM CDT Fri Aug 16 2024 Areas affected...southeastern Wisconsin and northern Illinois Concerning...Severe potential...Watch unlikely Valid 162231Z - 170030Z Probability of Watch Issuance...5 percent SUMMARY...Gusty winds locally -- with potential for a gust or two near severe levels -- can be expected over the next couple of hours across a portion of far southeastern Wisconsin and into northern Illinois. WW issuance is not expected, due to anticipated marginal/isolated nature of the risk. DISCUSSION...Latest radar loop shows that a semi-organized band of storms has developed over northwestern Illinois, ahead of a subtle, eastward-moving mid-level vort max embedded within the cyclonic flow surrounding the western Lake Superior upper low. A narrow axis of 1500 J/kg mixed-layer CAPE is indicated just ahead of the band of storms, which suggests continuation -- and possible/slight strengthening over the next 1 to 2 hours. The latest VWP from the KLOT (Chicago, IL) WSR-88D shows flow weakly veering from west-southwesterly to west-northwesterly with height, and increasing to around 35 kt at mid levels. This should allow storms to progress into the Chicago -- and possibly Milwaukee -- vicinity, accompanied by gusty winds. While a couple of gusts could near or reach severe levels, risk should remain sparse and marginal, and thus insufficient to warrant WW consideration. ..Goss/Edwards.. 08/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...MKX...DVN... LAT...LON 41899033 42458943 43088879 42888810 41938760 41438790 41418935 41899033 Read more

MD 1924 CONCERNING SEVERE THUNDERSTORM WATCH 628... FOR CENTRAL AND NORTHERN OKLAHOMA INTO FAR NORTHWEST ARKANSAS
Mesoscale Discussion 1924 NWS Storm Prediction Center Norman OK 0600 PM CDT Fri Aug 16 2024 Areas affected...Central and northern Oklahoma into far northwest Arkansas Concerning...Severe Thunderstorm Watch 628... Valid 162300Z - 170030Z The severe weather threat for Severe Thunderstorm Watch 628 continues. SUMMARY...The severe threat continues across Severe Thunderstorm Watch 628. At least a few instances of severe wind or hail may accompany the stronger storms over the next few hours. DISCUSSION...Multicell clusters and transient supercells have percolated in intensity from far western OK into far northwestern AR over the past few hours. At the moment, a couple of strong thunderstorm clusters are ongoing along diffuse baroclinic boundaries, were surface temperatures are in the upper 90s to low 100s F, contributing to 8.5-9.5 C/km boundary-layer lapse rates. As such, the more intense, persistent updrafts may support a large-hail threat until they become outflow dominant, when severe gusts become the main concern. However, deep-layer ascent/shear remain weak, so thunderstorms may continue to struggle to maintain intensity, with the severe threat perhaps becoming gradually more isolated through the evening. ..Squitieri.. 08/16/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...TSA...ICT...OUN...AMA... LAT...LON 35790001 36779902 37039498 36729390 36239357 35889366 35669546 35249766 35169872 35169943 35199997 35790001 Read more