Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
676 FXUS66 KPDT 302219 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 219 PM PST Sun Nov 30 2025 .KEY POINTS... 1. Cold overnight temperatures with patchy fog/freezing fog 2. Mountain snow returns Monday morning into Tuesday afternoon 3. Widespread rain and high mountain snow Thursday night through the weekend .DISCUSSION...Current satellite shows portions of the region to be clearing out with only high clouds lingering overhead. However, the eastern mountains through the Northern Blues still have a stratus deck overhead. The round of snow from last night averaged 1 in here at the office with other areas reporting a skiff to 0.5 inches of snow on the ground. Dry northerly flow has taken over today and will continue to usher in dry and cold temperatures through Monday morning. Today through Wednesday...Northerly flow will keep the region under cold and dry conditions. Low clouds have persisted over the eastern mountains and the Blues today mainly due to upslope flow. Cold air will continue to settle over the region through the overnight hours which will lead to patchy to areas of fog/freezing fog overnight into the morning through many of the valleys, basins and foothills of the Blues as well as areas along the Columbia River. Temperatures overnight will be below freezing across the entire region with all locations, except through the Gorge and isolated spots along the river, seeing temperatures below 32 degrees with well over 80% probabilities. Monday afternoon and into the evening, models show a shortwave ahead of a weak trough beginning to make its way towards the region. The shortwave will bring back snow showers to the WA Cascades and across the eastern mountains and the Northern Blues. 24 hour Raw guidance has 50-80% probabilities of 1-3 inches across the Northern Blues, Eagle Caps and higher elevations of the WA Cascades Monday night though Tuesday. Zooming in on the I-84 corridor, raw ensembles show 50-70% probabilities of near 2 inches of snow and along the I-90 corridor 30-50% probabilities of 0.5-1 inch of snow. Models show by Tuesday night the shortwave will have mostly cleared the region allowing northerly dry flow to dominate the region again. Dry and cold temperatures will dominate the region Wednesday ahead of the next incoming wave. Temperatures again will be below 32 degrees for much of the region with only the Gorge and isolated areas along the river seeing temperature at or slightly above freezing with 75- 95% probabilities. Thursday onwards...Models show another round of shortwaves making their way into the region beginning Thursday that will another round of mountain snow spreading to widespread rain across the lower elevations. Clusters do shift in phase a bit with the biggest discrepancy being in the timing of the event as well as amounts of precipitation expected. Models do show the heaviest amounts of precipitation will occur Thursday before slowly tapering off over the weekend. Snow levels will be over 4000 ft and increasing to above 6000 ft before decreasing to below 4000 ft Sunday. High elevation snow is expected, however, along the I-90 and I-84 corridors little to no fall is expected with this system with moderate confidence (60-70%). Much of the precipitation will fall as rain below 4000 ft with only slight chances (15-30%) through central/north central OR, the lower Columbia Basin of OR & WA and 30- 50% chances of 0.01-0.04 along the foothills. Highest amounts will be through the mid to upper elevations Friday. Saturday, precipitation looks to spill over along the eastern slopes of the Cascades and farther along the foothills with (50-70%) probabilities of those areas seeing between 0.01-0.05 inches of rain. Sunday will see dryer conditions across the lower elevations with only light rain across the eastern mountains with continued snow showers along the higher crests. All in all a moderate chance (60-70%) of having a wet weekend. 90 && .AVIATION...00z TAFs...Most sites will see VFR conditions this evening, save for ALW and BDN where low cigs persist, however some clearing has been observed for both sites this afternoon. Confidence remains shaky on the development of low clouds and fog overnight tonight, as colder air moving in combined with high clouds may inhibit fog development, but made mention of at least sct-bkn low cigs at a few sites since high pressure is moving in, which is generally favorable for fog and low stratus development. Otherwise, winds will remain light and terrain-driven. Another round of precip may arrive to the forecast area around the tail-end of the period. 74 && .PRELIMINARY POINT TEMPS/POPS... PDT 22 38 30 40 / 0 10 40 60 ALW 26 37 31 38 / 0 20 50 70 PSC 25 37 27 39 / 0 10 20 20 YKM 24 38 25 43 / 10 10 10 0 HRI 25 37 28 41 / 0 10 30 40 ELN 22 37 25 43 / 10 20 20 10 RDM 19 49 27 46 / 0 10 10 10 LGD 21 42 31 40 / 0 10 40 80 GCD 21 47 31 43 / 0 10 30 50 DLS 31 42 35 50 / 10 20 20 20 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...90 LONG TERM....90 AVIATION...74