textproduct: Seattle/Tacoma

SYNOPSIS

Upper level ridge over the area shifting east this morning. Splitting weather system arriving tonight into Wednesday morning. A series of systems will reach the area Wednesday night through Friday night. An upper level ridge will try to build Saturday before another system later in the weekend.

LONG TERM /THURSDAY NIGHT THROUGH MONDAY/

Extended models in good agreement with another frontal system Thursday night and Friday. Operational solutions build a ridge over Western Washington Saturday with a front stalled offshore. This is a good pattern for a very warm day this time of year. The weakening front moves inland late in the weekend. ECMWF ensembles in pretty good agreement with the operational run with very few wet solutions. The GFS ensembles are not as excited about the ridge with about half of the solutions remaining wet. Will keep a slight chance or chance of rain in the forecast through most of the weekend with the highest pops Sunday night. Upper level trough moving through Monday keeping precipitation in the forecast. Snow levels remaining above the passes through the period. Highs in the lower to mid 50s with the potential for some lower 60s Saturday if the ridge solution wins out. Lows mostly in the lower to mid 40s. Felton

AVIATION

An upper level ridge will continue to shift further inland this morning as an upper level trough approaches from the northeastern Pacific. Southwesterly flow aloft will become more southerly throughout the day as a result. Conditions at the area terminals are primarily VFR, with mid to high cloud cover streaming in ahead of a frontal system that will move into western Washington this evening.

Winds will remain light at 5 kt or less out of the E/SE across the interior terminals this morning, though winds for coastal sites will be a bit higher and will persist between 5-10 kt. Winds will then increase to 10-20 kt (with gusts to 25-30 kt possible) by this evening as the front approaches. Rain looks to arrive at the coastal terminals by late afternoon (00-03Z) and then push inland into the interior by this evening (03-06Z). Conditions generally look to remain VFR with the arrival of rain tonight, but look to gradually decrease to MVFR overnight into Wednesday morning.

KSEA...VFR conditions expected to persist at the terminal through the day. Light S/SE winds will continue at 5 kt or less this morning and will increase to 10-15 kt by this evening as the front approaches. Gusts to 20-25 kt will be possible at times tonight as the front moves through. Rain will likely make it into the terminal between 03-06Z. MVFR conditions expected to develop at the terminal by Wednesday morning.

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MARINE

A frontal system will move across the area waters today, bringing southerly gales to the coastal waters throughout the day and to the eastern Strait of Juan de Fuca as it moves inland this evening. Small craft southeasterlies are likely along the western Strait of Juan de Fuca ahead of the front and are also likely along Admiralty Inlet and the Northern Inland Waters as the front moves inland tonight. Seas across the coastal waters will build from 3-6 ft this morning to 10-14 ft by tonight.

Another system will move across the area waters Wednesday into Thursday, which looks to bring another round of gales to the coastal waters and to the eastern Strait (where latest guidance indicates roughly a 50-70 percent chance of gales redeveloping). In addition to winds, seas will build across the coastal waters to 15-20 ft late Wednesday into Thursday.

The pattern will remain active over the weekend, with additional systems expected to move across the area waters. Seas will gradually subside on Friday, but look to remain elevated and range between 10-12 ft through the weekend.

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HYDROLOGY

Multiple rounds of rain over the south slopes of the Olympics will cause the Skokomish River to rise beginning Wednesday. The river could reach flood stage as early as Thursday morning. More likely the river will reach flood stage later Thursday and remain over flood stage into Saturday. No river flooding expected on the remainder of the rivers. Felton

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory from 10 PM this evening to 4 PM PST Wednesday for Grays Harbor Bar.

Small Craft Advisory until 10 PM PST this evening for West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning from 7 PM this evening to 4 AM PST Wednesday for East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 7 PM this evening to 4 AM PST Wednesday for Admiralty Inlet-Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory until 1 PM PST this afternoon for Coastal Waters From Cape Flattery To James Island Out 10 Nm- Coastal Waters From James Island To Point Grenville Out 10 Nm-Coastal Waters From Point Grenville To Cape Shoalwater Out 10 Nm.

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

Small Craft Advisory until 3 AM PST early 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.

Gale Warning until 10 PM PST 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.