Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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356 FXUS66 KSEW 262210 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 310 PM PDT Fri Jul 26 2024 .SYNOPSIS...
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A weak upper level trough remains through the weekend. A passing front Monday will bring widespread rain chances to the area, with showers lingering into Tuesday as the upper trough moves through. Weak high pressure aloft begins to build again toward midweek.
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&& .SHORT TERM /TONIGHT THROUGH MONDAY/...
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Weak upper level troughing over the region this weekend for generally mild conditions. Temperatures will be close to late July normals. There is a slight chance of showers in the North Cascades (near the crest) Saturday afternoon, otherwise the remainder of western WA will be dry. A deeper trough taps into some moisture over the Pacific on Monday for wetter and cooler conditions. Much of western WA will see measurable rain with this system. Up in the mountains, there`s a 50-70% chance of seeing wetting rains (at least 0.25"). Temperatures will be cooler and in the 60s. 33 .LONG TERM /TUESDAY THROUGH FRIDAY/...Showers linger on Tuesday as the upper level trough exits east toward Idaho/Montana. Heights will build and we`ll see a little warming (but still a few degrees shy of normal). Dry and warmer weather returns mid-week onwards with broad upper level ridging over the western CONUS. Temperatures on Thursday and Friday will reach the 80s again (across the interior lowlands) with pockets of Moderate HeatRisk. NW flow will keep the coast cooler and in the 60s and 70s. 33
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&& .AVIATION...
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Northwest flow aloft as subtle ridging resides offshore along with troughing nearby. VFR across the area as terminals are under mostly clear skies. Tonight, marine stratus looks to march inland again but widespread intrusion isn`t expected. However, sites like KSHN, KOLM, etc. could see MVFR to potentially LIFR cigs along with KHQM into Saturday morning. Stratus will burn off towards the coast by the afternoon but could still remain around Hoquiam. KSEA...VFR expected for the remainder of the day and into Saturday. Surface winds north-northwest 6 to 10 kt this afternoon before decreasing and veering overnight into Saturday morning. McMillian
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&& .MARINE...
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Low-level onshore flow persists with high pressure over the coastal waters of the Pacific and lower pressure inland. Benign conditions over the marine zones today. A westerly push through the strait is certain this evening with a brief 30-40% chance of SCA level gusts for a few hours. However, not long enough for an advisory issuance. The next best chance appears to be Saturday night into Sunday morning for the east and central strait. Marine stratus will persist in varying coverage for the next several days with visibility restrictions a possibility over the zones. A frontal system will move through the region early next week. At this time the threat for widespread breezy winds impacting small craft is low. McMillian
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&& .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$