textproduct: Seattle/Tacoma

SYNOPSIS

Showers will linger into this evening then taper off completely for most areas. Precipitation will spread back into portions of the area Saturday morning and and again early Sunday. Another system is expected to reach the area Monday followed by drying and a return to unseasonably warm temperatures midweek potentially through Friday.

SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/

Wet and mild pattern continuing for the next couple of days. Lingering showers behind todays cold front will taper off during the evening with generally dry conditions for all but the mountains. This will be aided by an upper level ridge building over the area. A second system will brush the area Saturday morning, bringing rain for the coast and a period of lighter rain to much of the interior as the warm front moves to the north into British Columbia by midday. The afternoon looks to be generally dry - and fully in the warm sector such that high temperatures will reach into the mid to upper 50s and even lower 60s away from the water.

Rain returns to the coast Saturday evening ahead of a cold front which will work onshore and through the interior by midmorning. This will bring a bit heavier precipitation - on the order of 1/3 to 1/2 in to the coast and around a 1/4 in form much of the interior. Expect some gusty winds with the cold front on the order of 25 to 25 mph. Ensembles continue to consistently highlight a weak upper level shortwave clipping the area later Sunday afternoon/evening with about 20% of the grand ensemble trending a little bit stronger with this shortwave than the ensemble mean. This and a bit of cooler air aloft may bring a bit of instability late in the afternoon and evening to the coast and northern Olympic Peninsula where there looks to be around a 20% chance of thunder. Snow levels Sunday will start of in the 4500 to 5500 foot range with somewhat cooler air aloft helping then dip to around 4000 feet Sunday evening.

A period of elevated astronomical tides this weekend into early next week will keep the door open for the potential for minor coastal flooding. the best potential looks to be for the high tides Sunday primarily for sensitive areas along the coast, Puget Sound and Salish Sea.

LONG TERM /MONDAY THROUGH FRIDAY/

Medium range ensembles continue to consistently show another system brushing the area Monday on its way into British Columbia. Beyond monday the grand ensemble very consistently highlighting a 570 dm ridge settling along the West Coast into British columbia with the only significant variability in shortwaves riding over the ridge into into northern British Columbia or even well downstream. This pattern looks to continue through Thursday with ensemble clusters starting to indicate a shift Friday with nearly half of the grand ensemble members showing a chance of an upper level shortwave at least brushing the area late in the week. There remains relatively high confidence in generally dry conditions and unseasonably warm temperatures Tuesday through Thursday. As is often the case in these kinds of patterns there may also be periods of morning fog particularly in the more prone and shelter areas.

AVIATION

West to southwest flow aloft will continue into tonight as a frontal system exits and a weak shortwave upper ridge moves over the area. MVFR and localized IFR conditions will prevail into Saturday morning. Another warm front lifting northward across the area will produce a little light rain on Saturday.

KSEA...General MVFR conditions are expected to persist through Saturday morning. A general trend toward VFR ceilings is expected Saturday afternoon as a warm front exits the area. Surface winds southerly 7 to 10 knots this afternoon with a few brief higher gusts backing to east/southeasterly 7 knots or less tonight.

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MARINE

A series of rather weak frontal systems originating from a broad trough centered well offshore will continue to produce small craft advisory winds and seas for the coastal waters into the early portion of next week. Higher pressure at the surface and aloft over the interior of the Pacific Northwest will begin to deflect incoming systems further offshore toward the middle of next week.

Seas around 12 to 15 ft will slowly ease tonight to around 9-12 ft through the weekend. Weather systems passing by off to the west will keep seas in the 8-12 ft range going into next week.

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HYDROLOGY

With periods of precipitation today and tonight, the Skokomish River is expected to remain above minor flood stage into Saturday before dropping below flood stage late Saturday afternoon. It is expected to remain below but near flood stage through the remainder of the weekend. No flooding expected for the next 7 days for the other rivers in Western Washington. Felton

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 4 AM PST Saturday for Grays Harbor Bar-West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning until 4 PM PST this afternoon for East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory until 4 PM PST this afternoon for Admiralty Inlet-Northern Inland Waters Including The San Juan Islands-Puget Sound and Hood Canal.

Gale Warning until 1 PM PST this afternoon for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm-Coastal Waters From Cape Flattery To James Island Out 10 Nm- Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.

Small Craft Advisory until 4 PM PST Saturday for Coastal Waters From Cape Flattery To James Island 10 To 60 Nm- Coastal Waters From Cape Flattery To James Island Out 10 Nm-Coastal Waters From James Island To Point Grenville 10 To 60 Nm-Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.