ZCZC SPCSWOMCD ALL ACUS11 KWNS 172204 SPC MCD 172204 ORZ000-WAZ000-180000- Mesoscale Discussion 1673 NWS Storm Prediction Center Norman OK 0504 PM CDT Wed Jul 17 2024 Areas affected...northeast OR and eastern WA Concerning...Severe potential...Watch unlikely Valid 172204Z - 180000Z Probability of Watch Issuance...5 percent SUMMARY...Isolated to widely scattered dry thunderstorms will be capable of localized strong to severe gusts across parts of northeast Oregon into eastern Washington through mid-evening. The disorganized and localized nature of the threat will preclude a severe thunderstorm watch. DISCUSSION...Isolated high-based, low-topped thunderstorms are ongoing across parts of the Blue Mountains in northeast OR to the east side of the Cascades in southern WA. This activity is being aided by a minor mid-level impulse that will drift northeast across the region through this evening. Surface temperature-dew point spreads across the Columbia and Snake River Valleys are quite large from 60-65 F, with 50s spreads farther north in eastern WA across the Columbia Plateau. This is yielding a very deeply mixed thermodynamic profile which will be conducive to dry microbursts as thunderstorms gradually expand northeastward into early evening. The meager buoyancy and modest large-scale forcing for ascent should yield isolated to widely scattered convective coverage. The belt of enhanced mid/upper flow attendant to the minor impulse is consistently progged to remain on the backside of the convection to its south in eastern OR. This should inhibit appreciable organization, suggesting a spotty strong to severe gust threat. ..Grams/Gleason.. 07/17/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OTX...PDT... LAT...LON 44981891 45282025 45872075 47082076 47781970 47881897 47901846 47771745 46531718 44921827 44981891 NNNN