376 ACUS11 KWNS 222031 SWOMCD SPC MCD 222030 KYZ000-TNZ000-222230- Mesoscale Discussion 2088 NWS Storm Prediction Center Norman OK 0330 PM CDT Sat Aug 22 2026 Areas affected...portions of central and eastern Kentucky into northern middle Tennessee Concerning...Severe potential...Watch possible Valid 222030Z - 222230Z Probability of Watch Issuance...60 percent SUMMARY...The threat for at least isolated severe storms is expected to persist through this evening. Convective trends are being monitored for a possible severe thunderstorm watch. DISCUSSION...Over the past hour, thunderstorms have gradually increased in areal coverage from northeast into central KY, ahead of a cold front advancing into the northern part of the state. The inflow air mass to these storms is relatively hot and moist, leading to steep low-level lapse rates and MLCAPE ranging from around 1000 J/kg in northeast KY to as high as 2500-3000 J/kg near the confluence of the Mississippi and Ohio Rivers. Regional VWPs indicate gradually strengthening mid and upper-level winds this afternoon with deep-layer shear vectors oriented largely perpendicular to the surface front, especially over western and central KY. That is resulting in a semi-discrete storm mode with recent reports of hail up to one inch. Further strengthening of deep-layer shear is forecast through the remainder of the afternoon, potentially leading to a greater supercell and associated large-hail threat. Damaging wind potential may tend to increase by early evening, especially if some clustering of storms can occur. ..Mead/Smith.. 08/22/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RLX...MRX...JKL...ILN...LMK...OHX...PAH... LAT...LON 36878749 36948734 38378467 38518352 38288280 37598271 36858308 36118565 36138691 36348764 36878749 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  623 ACUS11 KWNS 222034 SWOMCD SPC MCD 222033 TNZ000-MSZ000-ARZ000-MOZ000-222230- Mesoscale Discussion 2089 NWS Storm Prediction Center Norman OK 0333 PM CDT Sat Aug 22 2026 Areas affected...Northeast Arkansas into western Tennessee and far northwest Mississippi Concerning...Severe Thunderstorm Watch 615... Valid 222033Z - 222230Z The severe weather threat for Severe Thunderstorm Watch 615 continues. SUMMARY...The early signs up upscale growth are noted across northeast Arkansas, hinting that the potential for severe winds is likely increasing downstream into western Tennessee and far northwest Mississippi. DISCUSSION...Over the past 40-45 minutes, reflectivity and velocity data from KLZK and KNQA have shown the early stages of semi-discrete cells merging and growing upscale into a more cohesive convective cluster. Cold pool amalgamation appears to be ongoing with embedded swaths of more intense wind now evident in KNQA velocity imagery. Downstream of this developing cluster, low-level lapse rates have steepened to 8-9 C/km as temperatures climb into the upper 90s. Additionally, the KNQA VWP is sampling 0-6 km BWD values on the order of 30-35 knots. Both of these factors will continue to favor organization and intensification of the emerging cluster (possibly into a more coherent linear structure) as it spreads southeast into western TN and far northwest MS over the next two hours. Based on recent convective trends, the downstream environment, and output from recent CAM guidance (which appear to be capturing ongoing trends well) the potential for 60-80 mph winds will likely increase as the cluster/line approaches the I-40 corridor. ..Moore.. 08/22/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MEG...LZK... LAT...LON 35058917 34658977 34509004 34439039 34569063 35429141 35589146 35699121 35939100 36139078 36229062 35578897 35318893 35058917 MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  483 ACUS11 KWNS 222049 SWOMCD SPC MCD 222049 IDZ000-UTZ000-NVZ000-222245- Mesoscale Discussion 2090 NWS Storm Prediction Center Norman OK 0349 PM CDT Sat Aug 22 2026 Areas affected...portions of northeastern Nevada into northwestern Utah and southern/eastern Idaho Concerning...Severe potential...Watch unlikely Valid 222049Z - 222245Z Probability of Watch Issuance...20 percent SUMMARY...A locally greater risk for damaging/severe wind gusts may develop across portions of the northern Great Basin through this evening. DISCUSSION...Scattered thunderstorms have developed across portions of the northern Great Basin, with a 61 mph wind gust recently recorded near Pocatello, ID. Modifying regional 18z observed soundings from BOI/LKN for current observations depicts deep, well-mixed boundary layer profiles with LCLs of 2.5-3.0+ km. Steepening low-to-mid level lapse rates below ~600 mb and modest surface dewpoints ranging from the upper 40s to lower 50s F have yielded the development of weak buoyancy (500 to locally 1000 J/kg MLCAPE) underlying enhanced southwesterly, deep-layer flow to the southwest of an upper low currently noted off the Pacific Northwest coastline. Broadly, this enhanced flow (and accompanying 25-35 kts of effective shear) along with inverted-v thermodynamic profiles should support scattered thunderstorms and a risk for isolated severe/damaging wind gusts across much of the northern Great Basin and northern Rockies. A locally greater risk for damaging/severe wind gusts (up to 60-70 mph) is expected to materialize across northeastern Nevada, northwestern Utah, and southern/eastern Idaho where recent observations and latest guidance suggest relatively greater storm coverage should intersect marginally more favorable mid-level flow and low-level moisture. While coverage of damaging/severe gusts may be locally greater within this corridor, the overall risk is expected to remain too isolated to necessitate watch issuance. ..Chalmers/Smith.. 08/22/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SLC...PIH...BOI...LKN... LAT...LON 41001245 39841382 39561480 40021537 40691555 41351551 42181528 43391448 43841414 44091370 44151300 44111231 43861183 43381147 42751161 41491207 41001245 MOST PROBABLE PEAK WIND GUST...55-70 MPH