FXUS66 KPDT 180539 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1039 PM PDT Sun May 17 2026 .KEY MESSAGES... - Scattered rain and snow showers and slight chance (10-15 percent) of thunder over Wallowa County today. Very low (5-10 percent) chance of showers and thunder elsewhere. - Mostly dry and warming conditions region-wide Monday through Saturday. && .DISCUSSION... Scattered rain and snow showers are ongoing across Wallowa County this afternoon as an upper-level trough digs southeast over the Great Basin, placing the Pacific Northwest under a cool northerly flow aloft. Through afternoon, there are low (10-15 percent) chances of thunder for Wallowa County, but have yet to observe any convection deep enough to produce lightning. Elsewhere, there are low (5-10 percent) chances of rain showers and thunder across the Washington Cascades and portions of south-central Washington and far northern Oregon. Monday through Saturday, warming temperatures and mostly dry conditions are forecast region-wide as an upper-level ridge of high pressure will likely (90-95 percent chance) build into the region from the Pacific and dominate the weather. A couple weak shortwaves passing through northwesterly flow aloft may facilitate some isolated showers for the mountains, but PoPs are low (generally 5-10 percent, except 15-35 percent for the northern Blues and Wallowa County on Monday). Breezy westerly winds are forecast through the Cascade gaps each day of the week, but not anticipating a need for any wind headlines. Thursday and Saturday have the highest chances (10-40 percent, and 20-60 percent, respectively) of reaching advisory-level winds through wind-prone areas of the lower elevations, primarily the eastern Columbia River Gorge, north- central Oregon, the foothills of the Blue Mountains, and the Kittitas Valley. The alternate, less-likely scenario (a closed low from Canada, with cool, showery weather between Wednesday and Thursday) from yesterday's discussion appears to have almost entirely dropped out of the ensemble envelope of solutions and does not appear in any cluster of ensemble solutions. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... VFR conditions will continue with sustained winds of 10-15 mph through the forecast period. No significant CIG or VIS issues at any sites. A few showers located just north of PSC and ALW will continue to dissipate going into the later evening hours. && .Preliminary Point Temps/PoPs... PDT 39 69 42 73 / 0 0 0 0 ALW 43 69 46 72 / 0 0 0 0 PSC 42 75 45 78 / 10 0 0 0 YKM 42 74 44 77 / 0 0 0 0 HRI 41 73 44 76 / 0 0 0 0 ELN 39 68 41 70 / 10 10 10 0 RDM 29 68 31 73 / 0 0 0 0 LGD 33 64 36 70 / 0 0 0 0 GCD 30 65 34 71 / 0 0 0 0 DLS 44 73 45 75 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... WA...None. OR...None. && $$ DISCUSSION...86 AVIATION...95