Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
697 FXUS66 KPDT 292247 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 247 PM PST Sat Nov 29 2025 .DISCUSSION...Much of the forecast area is covered by a deck of low clouds this afternoon, with some patchy fog reported along the foothills of the Blues, as northwesterly flow aloft pushes a cold air mass into the PacNW. Riding this NW flow will be a shortwave trough, which threatens to bring a round of snow to primarily the Blue Mountains and foothills this evening and overnight. The region will then fall under this cold NW pattern for much of the next week. In tracking this upcoming shortwave, hi-res models seem to shift the mid and upper-level winds more northerly behind the trough axis. This has resulted in a shift of the snow forecast away from the northern Blues and more toward the southern stretch of the mountains. Should continue to note that this system remains moisture- starved due to its continental polar origin, with NAM PWATs ranging in the 0.3 to 0.5 range, so much of the dynamics driving the precip in this system will be orographic. Even then, guidance generally only depicts about an inch or two of snow accumulations along the ridgetops of the southern Blues, with a hotspot around the Strawberries. Still, such patterns do favor orographic snow along the foothills of the Blues, would could potentially impact Pendleton. But with the more northerly track of this system, confidence has decreased a little on Pendleton receiving even a half inch of snow. Such a scenario isn`t inconceivable, but forecasting message around this system generally leans toward a `dusting` of snow rather than anything particularly impactful. Transitory ridging then moves in late Sunday into Monday, bringing with it the potential for more low clouds and fog in the Basin. The next system then looks to impact the forecast area late Monday into Tuesday. Models thus far favor a more northwesterly trajectory for this system, which would result in accumulating snowfall for the northern Blues more so than the southern, but confidence is low (30%) in this system resulting in any headlines, with only a couple inches currently forecasted for Meacham, Tollgate, etc. Ensembles suggest we`ll remain locked in this NW flow pattern through at least the end of next week, with intermittent precip chances materializing as shortwaves embedded within the flow regime sweep through the PacNW. 74 && .AVIATION...00Z TAFs...RDM/PSC are IFR due to low CIGs while BDN is MVFR and PDT/ALW remain LIFR. This will persist over the next forecast period. The clouds are fighting to lift with the only sites expecting to see VFR is DLS, then BDN/RDM later in the period. DLS/YKM are all VFR for now before DLS will see lowering CIGs and VSBY as the snow showers move across the sites. PDT/ALW will see a rain/snow mix around 03Z and lasting through 07Z while PSC/DLS have a 30% probability of also seeing a rain/snow mix during the same timeframe. The only site not plagued with FG/low CIGs and low VSBY is YKM which will remain VFR through the period. CIGs and VSBY will affect the remaining TAF sites through the entirety of the period. Low confidence on the timing (30%) when CIGs and VSBY will lift and then degrade will be the challenge through the period. 90 && .PRELIMINARY POINT TEMPS/POPS... PDT 25 37 23 38 / 60 0 0 0 ALW 28 36 26 37 / 40 10 0 10 PSC 24 39 24 36 / 20 0 0 0 YKM 23 42 24 38 / 10 0 0 10 HRI 26 39 24 37 / 40 0 0 0 ELN 21 39 23 37 / 10 0 0 10 RDM 23 39 19 49 / 20 10 0 0 LGD 26 40 21 43 / 60 0 0 0 GCD 26 39 22 47 / 60 0 0 0 DLS 32 44 30 43 / 20 0 0 10 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ DISCUSSION...74 AVIATION...90