Area Forecast Discussion
Issued by NWS Pendleton, OR
Issued by NWS Pendleton, OR
677 FXUS66 KPDT 151705 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 1005 AM PDT Sun Jun 15 2025 Updated Aviation Discussion .AVIATION...18z TAFs...VFR conditions expected. Skies will be mostly clear during the day, with light, terrain-driven winds less than 10 kts, except at DLS where winds could gust up to 20 kts at times in the afternoon. High clouds will build back in this evening, becoming ovc overnight. Evans/74 && PREV DISCUSSION... /issued 1255 PM PDT Sat Jun 14 2025/ SHORT TERM...Today through Monday...An upper-level low centered off the Gulf of Alaska will keep the PacNW locked into a SW flow pattern aloft for much of the next week, as building high pressure to our southeast keeps this pattern stagnant. This will allow breezy winds to remain relatively persistent through the Cascade Gaps and into the Basin through the next several days. Skies are mostly clear early this afternoon as mid-level flow and thus moisture transport is weak, but this will change later this evening as the aforementioned low circulates a weak shortwave through the forecast area, providing for more cloud cover over primarily the southern and eastern portions of the forecast area. CAMs tap into some slight chances for orographic showers across mainly the Wallowas Sunday afternoon, but given this oncoming cloud cover and unfavorable forecast soundings as far as instability is concerned, not expecting much in the way of moisture tomorrow. Slightly better rain chances materialize for Monday as a more organized shortwave moves through the PacNW, however our forecast area looks to largely be caught up in the dry slot of this system. A few CAMs (namely the NAMNEST) tap into some moisture along the eastern mountains, and the NAM picks up on better instability, but am not feeling more confident than 20% for shower and storm chances across the eastern mountains Monday afternoon based on what CAMs are currently showing. Evans/74 LONG TERM...Tuesday through Saturday...Ensemble guidance keeps this Alaskan low in place until around late Thursday into Friday. In the days preceding, however, winds will amplify along its southern flank, thus making for windy conditions through the Cascade Gaps and into the Basin for much of the period. NBM probabilistic guidance suggests a 40-50% for wind gusts to exceed 40 mph through the Gorge and Kittitas Valley each day Tuesday through Saturday, which will make for elevated wildfire spread risks, even as cooler air filters into the forecast area all the while and allows for better RH recoveries. PoPs also start to become relatively persistent from the midweek onward for the WA Cascades as this amplified flow supports at least light shower activity at crest level. Ensembles do generally agree that this low will finally push onshore by the end of the work week, making for, again, windy conditions, but also more widespread rain chances and cool conditions, with NBM temps suggesting widespread 70s and even 60s by the start of next weekend. So while the forecast area will get little in the way of relief as far as winds are concerned, the overall cooling trend does provide some form of promise for ongoing wildfire fighting efforts. Evans/74 && .PRELIMINARY POINT TEMPS/POPS... PDT 84 54 86 52 / 0 0 0 0 ALW 83 57 85 56 / 0 0 0 0 PSC 87 52 89 53 / 0 0 0 0 YKM 86 54 88 51 / 0 0 0 0 HRI 87 53 89 54 / 0 0 0 0 ELN 84 52 83 52 / 0 0 0 0 RDM 82 45 80 39 / 0 0 0 0 LGD 81 52 81 47 / 0 0 10 0 GCD 83 52 82 45 / 0 0 20 0 DLS 84 55 82 53 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ SHORT TERM...74 LONG TERM....74 AVIATION...74