Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000 FXUS66 KSEW 271559 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 859 AM PDT Tue Oct 27 2020 .SYNOPSIS...Mainly dry conditions across the region this week with high pressure. The exception is near the Canadian border where there`s a chance of rain due to a front in British Columbia. A cold front will bring showers to western Washington on Friday. The weekend is looking dry with high pressure. && .SHORT TERM /TODAY THROUGH THURSDAY/...Strong high pressure remains offshore today, yielding dry conditions under northerly flow. Temperatures warming across the area today through Thursday, with Thursday on track to be the warmest day of the week as temperatures climb back into the upper 50s and low 60s. A stalled frontal system over southern B.C. tonight into Wednesday will increase POPs along the northern border and potentially along the northern slopes of the Olympics. Light rain is possible in these regions. Kristell .LONG TERM /FRIDAY THROUGH MONDAY/...Wetter weather returns on Friday as a cold front clips through western WA (average looking front). Snow levels in the Cascades will lower to around 4500-5000 feet behind this system Friday night but showers will also taper off. High pressure will rebuild over the region Saturday and Sunday for another break in the weather. A wetter, stronger system may track inland Monday or Tuesday as the ridge exits. 33 && .AVIATION...Upper ridge offshore will gradually weaken over the next 24 hours as stalled frontal boundary well to the northwest of the region sags southward. Northwest flow aloft to continue today with light flow in the low levels. The air mass remains somewhat moist below about 6000 feet and expect mostly VFR ceilings to persist across the region through the day ahead. Light surface flow will allow ceilings to lower tonight with widespread low MVFR or IFR likely on Wednesday morning. KSEA...VFR ceilings expected to persist today. Some improvement expected this afternoon, but broken to overcast 5000 to 6000 feet is likely to remain in place this afternoon. Ceilings lowering down to 1000-2000 feet around 12z Wednesday. Surface winds light southerly. 27 && .MARINE...High pressure over the waters will gradually weaken through Thursday as a frontal boundary near Haida Gwaii gradually sags southward toward northern Vancouver Island and stalls. A somewhat stronger front will arrive Friday with small craft advisory winds possible over most of the waters. Winds will ease Friday night and Saturday as high pressure rebuilds over the area. Felton && .HYDROLOGY...No river flooding expected over the next 7 days. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...None. && $$ www.weather.gov/seattle

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