Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000 FXUS66 KSEW 251616 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 915 AM PDT Mon Sep 25 2017 .SYNOPSIS...
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A weak front will break up over the area this afternoon. A ridge with warm dry air and low level offshore flow will shift over the region by Wednesday. A front is likely to reach the area Friday.
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&& .SHORT TERM...
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A weak front is moving over the area today and it has been a drippy morning with some rain at times--mainly from Seattle north. The front will break up this afternoon and precip on the radar ought to dry up. A ridge will build into the region through Tuesday and Wednesday with dry warm air and low level offshore flow by Wed. .LONG TERM...Onshore flow will develop Thursday night ahead of a front that might should reach the area on Friday for some rain. Saturday could be a little drippy with clouds and a few showers, maybe a PSCZ. Saturday night and Sunday could be dry and then a stronger frontal system is shown by the 06z GFS reaching the area Sunday night and Monday with some heavy rain and a deep low.
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&& .AVIATION...
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Northerly flow aloft will continue. A weak frontal system moving across western Canada will result in light low level southerly flow and light precipitation today. Expect areas of MVFR CIGs/VSBYs during the day. The mtns will be obscd. KSEA...In general, expect VFR conditions through this evening. There will probably be occasional MVFR CIGs this afternoon. MVFR CIGs are more likely late tonight or early Tuesday. Light southerly winds will become light and variable tonight.
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&& .MARINE...
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A weak frontal system passing north of the WA coastal waters today will result in southerly flow across the area. The flow will become northerly on Tuesday, and then offshore or easterly on Tuesday. Onshore flow will return late Thursday.
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&& .SEW WATCHES/WARNINGS/ADVISORIES...
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WA...None. PZ...Small Craft Advisory until 6 PM PDT this evening for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm- Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm.
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&& $$ www.weather.gov/seattle An illustrated version of this forecast discussion can be seen at www.wrh.noaa.gov/sew/gafd/latest_webafd.html

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