textproduct: Seattle/Tacoma

SYNOPSIS

A frontal system will continue to bring widespread precipitation and breezy conditions to Western Washington today. Unsettled conditions are favored into next week. Light showers will linger early next week. Another system will arrive midweek, bringing widespread rain, mountain snow, and cooler temperatures to the region.

SHORT TERM /TODAY THROUGH TUESDAY/

Steadier precipitation continues to move from Puget Sound east into the Cascades with scattered showers along the coast and offshore. Rainfall amounts over the last 24 hours have ranged from 0.50-1.50" along the majority of the Olympic Peninsula, and 0.20-0.50" for Puget Sound, with lower amounts into the Cascades. Showers at times will continue through today with a system lingering offshore. Southeast winds remain a bit breezy at times along the coast, San Juan Islands, and Admiralty Inlet into the afternoon with gusts up to 25 to 35 MPH. High temperatures in the low to mid 50s today.

Models have come to a better agreement on the projected path of the low. The center of the low will remain offshore today and move inland Monday morning near the Oregon/Washington border. This will result in light showers lingering into Monday. A weak shortwave will slide down from British Columbia on Tuesday for another chance of light precipitation.

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LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/

There is good agreement among models that a low pressure system will slide down from the British Columbia coast late Tuesday towards Western Washington, bringing another round of widespread precipitation through at least Thursday. Additionally, a colder air mass will accompany this system. Latest guidance suggests high temperatures will only peak into the upper 40s to low 50s and overnight temperatures will dip into the 30s, with upper 20s possible in the valleys by Thursday. Snow levels will also decrease below 3500 ft with this system, bringing light snow accumulations to the passes. Latest guidance suggests the passes may receive around 4 inches of snow, while the higher mountain peaks may see around 7 inches. Models start to struggle Saturday on the upper-level pattern. Some members have a weak ridge building behind the low pressure system, however the majority of members at this time favor an upper-level trough to remain over Western Washington.

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AVIATION

Southwest flow aloft will become southerly later today then southeasterly overnight as an upper low offshore moves onshore over northwest Oregon. Ceilings are a mixed bag across the region this morning as bands of precipitation associated with the system continue to move across the region. MVFR ceilings will be mostly confined to the coastal areas with primarily VFR for interior terminals. Ceilings may briefly drop to MVFR thresholds for interior in any heavier precipitation.

KSEA...Mainly lower end VFR expected today with periods of rain moving through the terminal into this afternoon. Precipitation should begin to taper by this evening. Surface winds NW 4 to 8 kt will shift to the NE through the morning hours.

27/14

MARINE

A gradually weakening surface low will shift southward over the offshore waters today before moving onshore over the northern Oregon coast on Monday morning. Small craft advisories remain in effect for a combination of wind and seas over the coastal waters into this evening. Small craft advisories also remain in effect for easterlies in the strait. Winds and seas will be ease and subside tonight as the low offshore further weakens and moves ashore over Oregon. Another front will reach the waters on Wednesday, likely bringing the next round of more widespread headlines to the area waters.

Seas between 9-12 ft today will gradually subside towards 4 to 6 ft on Monday.

27/14

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 5 PM PDT this afternoon for Grays Harbor Bar-Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory until 11 PM PDT this evening for Central U.S. Waters Strait Of Juan De Fuca-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-West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning until 5 PM PDT this afternoon for East Entrance U.S. Waters Strait Of Juan De Fuca.