textproduct: Seattle/Tacoma

SYNOPSIS

High pressure aloft will begin to rebuild across Western Washington on Wednesday and remain in place into Friday for a return to some sunshine and warmer temperatures. The ridge will weaken over the upcoming holiday weekend for a cooling trend and a chance of rain by Memorial Day.

SHORT TERM /TODAY THROUGH FRIDAY/

Broad upper-level troughing resides over western CONUS while a ridge continues to remain just offshore the PNW. Mid-high level cloud coverage is streaming overhead under northwest flow as the ridge axis stretches well into northern BC. Low stratus has developed again this morning across the coast, southwest interior and Puget Sound. It'll become more widespread as the morning progress before giving way to high clouds and filtered sunshine during the afternoon. High temperatures are forecast to be around average - in the 60s across the interior with lower 70s throughout the Chehalis River valley. Overnight lows will fall into the 40s.

Upper-ridging is likely to amplify on Thursday before flattening on Friday. Temperatures will warm readily into the 70s to near 80 F across the interior for both Thursday and Friday. Coastal areas will see afternoon highs in the 60s with lows in the 40s area- wide.

LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/

Zonal flow aloft by Friday night along with more onshore flow towards the weekend. This should not only bring cooler temperatures, but also increase the chance for widespread PoPs into early next week. Sunday should feature additional cooling and cloud cover with precip chances increasing areawide Sunday night into Memorial Day.

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AVIATION

High pressure is anchored offshore with N/NW flow over western WA today. The low level flow remains onshore. There are pockets of MVFR ceilings along the coast and in the interior this morning. The trend is for improving conditions and VFR by 18-21z in the interior and 21-00z along the coast. Low clouds will reform along the coast overnight. 33

KSEA...MVFR conditions this morning with improving conditions 18-21z. Light/variable wind becoming N/NW to 10 kt this afternoon. VFR conditions tonight. 33

MARINE

Onshore flow will prevail this week with high pressure offshore and lower pressure inland. Expect diurnal westerly pushes through the Strait of Juan de Fuca with highest wind and waves during the late afternoon and evening hours. A system Friday will bring elevated winds and seas over the Coastal Waters. 33

HYDROLOGY

The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated during this time as needed.

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 5 AM PDT early this morning for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 5 PM this afternoon to 11 PM PDT this evening for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory until 11 AM PDT this morning 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.