textproduct: Seattle/Tacoma

UPDATE

Satellite imagery shows a little fog left along the Chehalis river going into Grays Harbor otherwise mostly clear skies over Western Washington this morning. Temperatures with the sunny skies are already in the 50s with a few locations near 60 at 9 am/16z. Forecast on track with a pair of sunny and warm days in store today and Friday. Highs in the mid to upper 60s along the coast and upper 60s to upper 70s inland. Transition to onshore flow over the weekend will cool things down with the next system due into Western Washington Memorial Day. No update this morning. Previous discussion follows with updated aviation and marine sections. Felton

SHORT TERM /TODAY THROUGH SATURDAY/

Broad upper-level troughing resides over western CONUS while an upper-ridge is nosing into BC and W WA. Mostly clear skies across the CWA this morning aside from marine stratus along sections of the coast and southwest interior. This activity along with patchy river valley fog will continue before burning off as the morning progress. Mostly sunny skies today as large- scale subsidence ensues. High temperatures are forecast to be above average - in the 70s across the interior with near 80 F throughout the Chehalis River valley. Coastal areas to remain in the 60s. Overnight lows will fall into the 40s and lower 50s.

Upper-ridging will flatten on Friday as zonal flow switches into gear on Saturday. Temperatures will warm into into the 70s again for both Friday and Saturday but low-level onshore flow will also begin to strengthen. Coastal areas will see afternoon highs in the 60s with lows in the 40s and lower 50s area-wide.

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

Deterministic guidance continue to hold off rain over the interior until late Monday. However, ensembles are more progressive with an earlier arrival of the front late Sunday. This is in the current forecast with a chance of rain Sunday night and rain spreading over the area on Memorial Day. Upper- troughing on Monday/Tuesday before another ridge noses into the region towards midweek.

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AVIATION

High pressure will bring dry and stable conditions to western WA today. The flow aloft is northerly. Fog/stratus is dissipating at HQM this morning should lift before 18Z this morning. VFR conditions should prevail for most through the rest of the TAF period. Another round of stratus along the coast will likely bring IFR conditions to the coast and may push a bit farther inland, but it should stay west of the Puget Sound interior terminals. Higher likelihood of occurrence at terminals such as OLM, PWT, and CLM (30- 50% probabilities). Winds remain N/NW 5-10 kt today, becoming light NE overnight.

KSEA...VFR conditions prevail through the TAF period. Winds N/NW 5- 10 kt today, becoming light (<5 kt) NE overnight.

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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. Stronger onshore flow Saturday evening does have the potential to produce gales through the Strait. A low pressure system Monday will likely produce widespread Small Craft conditions through the area waters.

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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 from 5 PM this afternoon to 5 AM PDT Friday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 2 PM this afternoon to 11 AM PDT Friday 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.