ACUS11 KWNS 222205 SWOMCD SPC MCD 222204 MTZ000-IDZ000-ORZ000-WAZ000-230000- Mesoscale Discussion 2092 NWS Storm Prediction Center Norman OK 0504 PM CDT Sat Aug 22 2026 Areas affected...portions of the Columbia Basin and northern Rockies. Concerning...Severe potential...Watch unlikely Valid 222204Z - 230000Z Probability of Watch Issuance...5 percent SUMMARY...Isolated damaging gusts and perhaps some hail are possible with scattered thunderstorms across WA, northern ID and into western MT. While an isolated severe storm is possible, a WW is unlikely. DISCUSSION...As of 22 UTC, GOES WV imagery showed an arc of convection ongoing from the Columbia Basin to the northern Rockies associated with an upper low off the WA/OR coast. Diurnal heating of a modified/remnant monsoon air mass has resulted in weak buoyancy over much of the Northwest. Scattered thunderstorms have developed across the higher terrain and a weak wind shift across the western Columbia Basin. Storm coverage is forecast to increase over the next couple of hours through peak heating, coinciding with some intensification of the ongoing/anticipated storms. A belt of stronger southwesterly flow aloft is overspreading the weakly unstable air mass, supporting elongated mid and upper-level hodographs. This could result in some modest storm organization into clusters or transient supercells. Steep low and mid-level lapse rates, especially closer to the upper low over WA where mid-level temperatures are cooler, could support a few stronger updrafts capable of marginally severe hail and damaging downburst winds. While an isolated severe risk is possible from WA into northern ID and northwest MT, the weak buoyancy and limited moisture should limit overall storm organization/intensity such that a WW is unlikely. ..Lyons/Thompson.. 08/22/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TFX...PIH...MSO...BOI...OTX...PDT...SEW... LAT...LON 47941313 46741237 45141194 44021274 44451443 44911552 46581763 47031840 47151893 47141990 47202040 47412096 47752118 48602120 49022098 49142051 49131704 49081484 47941313 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN