


Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA
Issued by NWS Seattle/Tacoma, WA
637 FXUS66 KSEW 141002 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 302 AM PDT Tue Oct 14 2025 .SYNOPSIS...Weak high pressure building into the region, combined with offshore flow, will bring cool and dry conditions to western Washington today and Wednesday. Showers will return Thursday into Friday as a weak system moves into the area. A stronger, wetter system moving into the area over the weekend will bring locally gusty winds, lowland rain, and another round of snow for the mountains. && .SHORT TERM /TODAY THROUGH THURSDAY/...Weak high pressure building back into the region, combined with offshore flow, will bring cool and dry conditions to western Washington today and again on Wednesday. Clear skies and lighter winds overnight have allowed for temperatures across portions of the interior to dip down into the mid 30s already this morning for areas across the southern Sound. A Frost Advisory remains in effect for much of the interior lowlands with overnight lows still on track to bottom out in the low to mid 30s (the coolest temperatures of the season so far). Morning temperatures on Wednesday will be cool as well, with many areas likely seeing another round of morning frost. Winds will transition back to onshore during the day on Wednesday and afternoon highs both days will be in the upper 50s to mid 60s under sunny skies. Shower chances will start to increase along the coast during the day on Thursday as a weak frontal system approaches the region. Expect showers to push further inland into the interior Thursday night into Friday as the frontal system slowly starts to make its way inland. Rainfall amounts look to remain rather light, with most areas likely only seeing a few hundredths of an inch. Morning low temperatures on Thursday will be in the upper 30s to mid 40s across the area, with afternoon highs expected to be in the upper 50s to mid 60s. .LONG TERM /FRIDAY THROUGH MONDAY/...Light showers will linger across the region on Friday, however the focus in the long term then shifts to the weekend as a stronger, wetter weather system is slated to move into western Washington. This system has the potential to bring locally gusty winds, lowland rain, and another round of snow to the mountains Saturday night into Sunday. Ensemble clusters then look to favor upper level troughing remaining over the region into Monday for an unsettled start to early next week. 14 && .AVIATION...An upper-ridge will position over BC today bringing dry northeasterly flow aloft. As a result, VFR skies are expected throughout much of the upcoming TAF period for area terminals. Must express the development of patchy valley fog this morning. KOLM is mostly likely to see impacts with a period of IFR/LIFR possible between 12-16z. As mentioned, mostly VFR through tonight. However, an additional period of patchy fog is favored to develop into early Wednesday morning as well. Northerly surface winds are expected. KSEA...Mostly clear skies throughout the TAF period. North-northeast surface wind 6 to 12 kt becoming lighter tonight into Wednesday morning. McMillian && .MARINE...High pressure over area waters through Thursday. Here we`ll see a period of light onshore flow and calmer seas compared to what we`ve experienced recently. The next system will arrive Thursday night into Friday but latest guidance indicates this disturbance won`t pack much of a punch but we could see an increase in seas. However, a more impactful front will enter around the Saturday-Sunday timeframe with a better chance for widespread advisories and warnings. Combined seas remaining around 4 to 6 feet through midweek before potentially rising above 10 ft towards the weekend. McMillian && .SEW WATCHES/WARNINGS/ADVISORIES... WA...Frost Advisory until 8 AM PDT this morning for Downtown Everett / Marysville Area-Foothills and Valleys of Central King County-Foothills and Valleys of Pierce and Southern King Counties-Foothills and Valleys of Snohomish and Northern King Counties-Foothills and Valleys of Thurston and Lewis Counties-Foothills and Valleys of the North Cascades- Lowlands of Lewis and Southern Thurston Counties-Lowlands of Western Skagit and Northwestern Snohomish Counties- Middle Chehalis River Valley-Olympia and Southern Puget Sound-Southern Hood Canal. PZ...None. && $$