690 FXUS66 KPDT 251835 AFDPDT Area Forecast Discussion...UPDATED AVIATION DISCUSSION. National Weather Service Pendleton OR 1135 AM PDT Thu Sep 25 2025 .AVIATION...18z TAFs...VFR conditions currently prevail area-wide and are expected to continue over the next 24-hrs. A dry cold front is starting to work into northwest WA that will eventually enter and cross the area late this afternoon. Ahead of the front, breezy W-NW winds are anticipated with some terminals starting to see winds increase, such as KPDT. These increasing winds late morning-early afternoon could be attributable to strong cross-Cascade pressure differences that is sharpening. These breezes will then be maintained as the front moves through promoting breezy winds through the evening hours. Winds should start subsiding 3-9 UTC tonight with light winds prevailing the remainder of tonight. Otherwise, increasing high clouds are expected this evening-overnight. && .PREV DISCUSSION... /issued 335 AM PDT Thu Sep 25 2025/ DISCUSSION...A weak dry cold front will pass over the region Today, creating conditions for locally driven downslope mountain gap winds and resultant impacts to fire weather. Noon to roughly midnight will be the timeframe to expect breezy to windy conditions through the Cascade Gaps and areas downstream. West winds developing from The Dalles to Hermiston could gust to around 35 mph commonly while farther north in the Kittitas valley, gusts in the 45 to 50 mph range look possible based on NBM 75th percentile members. Not counting the cooler air on Friday behind the cold front, the downsloping winds will contribute to warmer temperatures in the 80s across most of the lower elevations through Sunday. As a surface trough/dry cold front exits the region Tonight, the relaxing pressure gradients allow the winds to weaken in the windy areas and temperatures Friday become capped in the 70s across the lowers elevation and even 60s and upper 50s in some of the Eastern Mountains. Large Fire Potential (weather component) is enhanced across the Kittitas valley and Columbia Gorge/Basin areas beginning by around noon Today, and tapering off this evening. The Kittitas valley hangs onto the enhanced fire weather conditions a bit longer and winds are slower to subside in these areas as also pointed to by the wind advisory for the valley which is in effect beyond midnight. The Red Flag Warnings continue for the same areas; Fire Zones WA690 WA695 WA691 OR691 OR701 OR703. Winds and fire weather impacts will subside on Friday as high pressure develops across the region behind the exiting front. By the middle of the weekend, more cloud cover, a bump in moisture small (under 10%) chances for thunder but a more robust 40-60 % chance for showers across the eastern mountains and a 20-40% chance everywhere else in the Monday, Monday night and early Tuesday timeframe. 71/RUSSELL && .PRELIMINARY POINT TEMPS/POPS... PDT 82 46 72 46 / 0 0 0 0 ALW 82 50 72 51 / 0 0 0 0 PSC 83 46 74 45 / 0 0 0 0 YKM 82 45 75 48 / 0 0 0 0 HRI 83 47 74 46 / 0 0 0 0 ELN 73 43 71 45 / 0 0 0 0 RDM 82 35 73 38 / 0 0 0 0 LGD 84 42 71 43 / 0 0 0 0 GCD 85 40 73 44 / 0 0 0 0 DLS 78 49 78 51 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...Red Flag Warning from 1 PM this afternoon to 11 PM PDT this evening for ORZ691-701-703. WA...Red Flag Warning from 1 PM this afternoon to 11 PM PDT this evening for WAZ691. Red Flag Warning from 11 AM this morning to 11 PM PDT this evening for WAZ690-695. Wind Advisory from 11 AM this morning to 2 AM PDT Friday for WAZ026. && $$ SHORT TERM...71 LONG TERM....71 AVIATION...80