textproduct: Seattle/Tacoma

SYNOPSIS

Light showers and cloudy conditions will continue across western Washington this afternoon as a weak frontal system moves across the area. A stronger, more fall-like system will move through the region Thursday night into Friday, bringing more widespread rain and some gusty winds to western Washington. Drier conditions are expected this weekend, however additional chances of precipitation will return to the area by early next week.

SHORT TERM /TONIGHT THROUGH FRIDAY/

Upper level troughing remains situated over the Pacific Northwest today, while a weak surface front pushes out of the area this afternoon. Conditions remain cooler and cloudier across portions of the interior as a result. Expect low clouds to scatter over the next few hours for a mix of mid to high clouds and some sun later this afternoon. High temperatures will be in the 60s area- wide.

A stronger, more fall-like system will move into the area Thursday night into Friday, bringing more widespread rain to western Washington and some gusty winds to the coast and the Strait of Juan de Fuca. Showers will start to move in along the coast by Thursday afternoon, with rain becoming more widespread Thursday night into Friday morning. Most lowland locations will receive between half an inch to an inch of rainfall, with the Olympics and Cascades likely to receive between an inch and an inch and a half of rain. Rain will taper to showers through the day Friday as the upper level trough axis swings across the region. A slight chance of thunderstorms will be possible Friday afternoon and evening as conditions become more unstable in its wake. Snow levels falling between 5000-6000 ft by late Friday night will bring the first dusting of snow of the season to the higher peaks in the Cascades. Winds will increase across the area on Friday as a surface low approaches the coast. The strength of the winds will be highly dependent on the low's track, with the most likely scenario, at this time, highlighting wind gusts reaching 35-45 mph along the coast Friday morning. Should the track shift further northward, there remains a small, roughly 10 percent chance, that the Grays Harbor County coast could see a brief period of gusts exceeding 55 mph. Outside of the coast, expect the strongest winds to be along the Strait of Juan de Fuca Friday afternoon and evening, where gusts to 35-45 mph are likely.

Cooler temperatures are expected Thursday and Friday, with afternoon highs only expected to top out in the upper 50s to low 60s. Morning lows will be in the mid 40s to low 50s.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/

A few showers may linger across the North Cascades into Saturday morning, but expect overall conditions to dry out over the weekend. Temperatures will remain cool and below normal, with afternoon highs expected to be in low to mid 60s and morning lows expected to be in the 40s. Chances of rain return again early next week as ensembles lean more towards upper level troughing moving back over the Pacific Northwest. Cooler and wetter conditions then look to persist heading into midweek.

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AVIATION

A weak front continues to slowly push through western Washington this afternoon. Primarily VFR conditions are expected, particularly in the wake of the front. Southerly winds 5-10 kt are being observed ahead of the front, shifting to the north/northwest in its wake. A similar mix of low VFR/MVFR is expected Thursday morning ahead of a wet system moving through late Thursday & Friday with rain. CIGs are expected to lower to at least 2-4kft by Thursday afternoon/evening with widespread rain expected by Thursday evening through Friday.

KSEA...VFR conditions favored through the TAF period (although brief MVFR ceilings cannot be completely ruled out). Southerly winds 5-10 kt turning to the north this afternoon (currently expected within an hour or so of 00z). Wet conditions with lower CIGs are expected late Thursday through Friday.

Wolcott

MARINE

High pressure will build back over the coastal waters this evening in the wake of a frontal system that pushed through the area this afternoon. Onshore flow will continue, with another push of westerly winds expected along the central and eastern Strait of Juan de Fuca this afternoon and evening. While a few gusts to 25 kt will be possible, gusts are largely not expected to be widespread enough for any small craft advisory issuance.

A more organized frontal system will move across the area waters Thursday into Friday, bringing an increased likelihood of small craft strength winds to the coastal waters and of gales to the Strait. Latest probabilistic guidance highlights the strongest winds expected to be along the Strait Friday afternoon and evening, with roughly a 50-80 percent likelihood of gusts exceeding 34 kt.

Conditions will then ease again over the weekend as high pressure builds back over the coastal waters. A weak system looks to approach the area from the NE Pacific on Sunday, but looks to dissipate before making it into the area waters.

Seas will range between 5-8 ft through Thursday. Seas will then build between 9-12 ft on Friday in the wake of the system, before subsiding back towards 4-6 ft over the weekend.

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SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...None.