


Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
931 FXUS66 KPDT 182042 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 142 PM PDT Wed Jun 18 2025 .SHORT TERM...today through Saturday morning...Radar depicts clear skies across our CWA, however its a different story with stratus covering most of the area west of the Cascades. This has caused some temperature gradient between the regions, and as a result has enhanced the winds near the gap in the Cascades. Nothing to suggest Wind Advisory at this time since intensity and/or area coverage doesn`t suffice to issue a highlight. The rest of the short term will be characterized as the trough system moving from the Pacific into our region. Moisture advection and increased vorticity values in the mid-levels will result in some slight chance of thunderstorms across the Eastern Mountains Friday morning. Area coverage of light precip becomes widespread by Friday afternoon into Friday evening as that system moves closer to the region. Most areas will experience <.10" of precip (>85% chance) with higher values located in the higher peaks Snow levels will drop to around 5500-6000 feet, resulting in some light mountain snow for portions of the mountain regions. Not expected to reach a critical amount of QPF regarding mountain snow (<.10") and any is expected to last no more than a few hours. A brief break in precip (especially across portions of the BAsin) is expected in the early moorings Saturday as the mid-level system passes through the region. .LONG TERM...Saturday morning through Wednesday...Following the system from Saturday morning, it will pass to the east heading into the later part of the weekend. As the system moves east, wrap-around precip will again bring light rain chances. Chances for some light mountain snow returns late Saturday morning/afternoon with snow levels dropping to 5000-5500 feet (65-75% chance), reserving the chances to the higher peaks in the mountain regions. Precip chances decrease significantly region wide heading from Sunday evening onwards as the trough continues to push east and have less influence on the overall weather pattern. This is thanks to the mid-level pattern becoming more zonal orientated, cutting off moisture advection. Temperatures will start a warming trend Monday onwards thanks to clearing skies and lack of precipitation. Will need to monitor how intense temperatures will become moving forward, but NBM currently advertises highs in the 90s across much of the Basin by Wednesday. Confidence is currently low to medium if temperatures reach this high. && .AVIATION...18Z TAFs...VFR conditions are expected to remain for the entire period. No precip expected, however winds do remain the primary threat as we head into the next 24 hours for many of the sites. Sites near the Cascade gaps (DLS) and PDT will see continuous gusty winds up to 25 knots for the majority of the period, while the rest of the sites will see winds pick up at around 21Z. Winds will trend down as peak speeds occur in the late afternoon, then gradually decrease to 5-12 knots by the tail end of the period. && .PRELIMINARY POINT TEMPS/POPS... PDT 49 78 53 69 / 0 0 10 10 ALW 53 77 56 67 / 0 0 10 20 PSC 49 80 54 74 / 0 0 0 10 YKM 48 80 54 72 / 0 0 0 20 HRI 49 80 55 71 / 0 0 0 10 ELN 47 78 51 66 / 0 0 0 20 RDM 38 75 40 60 / 0 0 0 30 LGD 47 76 50 62 / 0 0 20 30 GCD 46 81 48 63 / 0 0 20 20 DLS 51 76 54 66 / 0 0 0 20 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...&& $$ SHORT TERM...95 LONG TERM....95 AVIATION...95