textproduct: Seattle/Tacoma

UPDATE

The bulk of the stratiform rainfall with the first autumn-like weather system of the year has shifted northeastwards, with showers and isolated thunderstorm activity streaming inland this evening. Areas on the Olympic Peninsula have generally seen rainfall amounts of up to an inch, with locally higher amounts over the Olympic Mountains. Most inland lowland locations have seen lighter amounts, up to a quarter of an inch, and areas over the Cascades have seen around half an inch of rainfall with this system. In addition, gusty winds have begun to gradually decrease, and the Wind Advisories have been allowed to expire. No further forecast updates tonight outside of the Aviation and Marine sections below.

SYNOPSIS

A vigorous early season storm system has moved through the area, with lingering showers and breezy winds overnight. The overall weather pattern will remain cool and unsettled through the weekend with possible drying and warming following early next week.

SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/

Steady rain will continue to change to showers behind the cold front this evening, with winds gradually easing tonight. The associated upper level low will linger over the region Thursday and Friday - keeping the overall pattern relatively cool and unstable - with showers and 15 to 25% chance of afternoon and evening thunderstorms especially over the mountains.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Ensemble-based clustering systems continue to emphasize the likelihood of the upper level low/trough remaining over the Pacific Northwest through the weekend. Differences in the forecast remain largely limited to differences with embedded features or whether or not the upper level low opens up and lingers as a trough (17% of the members) or lingers as a more consolidated upper level low (83% of the members). Ultimately this equates to a high degree of confidence in the cooler unsettled pattern lingering through the weekend, with showers and potentially potential isolated thunderstorms especially over the mountains. Ensemble clusters show the pattern opening up early in the week, allowing the upper level system to shift eastward with much of the variability in how progressively this occurs. 15% of the members falling into a more progressive or faster scenarios at day 6 (Monday), and the bulk of the remaining members pushing the change into Tuesday. The overall message remains for a transition to drier and relatively warmer conditions early next week.

AVIATION

South to southwest flow aloft into Thursday an an upper low digs southwards along the Washington coast. Scattered showers continue to move across the area this evening. A 20-25% probability for thunderstorms remains along the coast tonight. VFR cigs for most areas tonight with MVFR along the coast and in areas of heavier rain. Cigs may slowly lower towards higher end MVFR for localized Puget Sound terminals and Kitsap Peninsula Thursday AM. A more widespread chance for isolated thunderstorms is possible on Thursday, with probabilities ranging between 20-30%. Winds continue to ease this evening, however a few terminals will continue to see breezy winds from PAE northwards.

KSEA...VFR conditions are expected to continue overnight. A few showers will linger tonight into Thursday. Cigs slowly lower towards low-end VFR and high-end MVFR Thursday morning, with a 30-35% chance of MVFR cigs between 16 to 19z Thursday. Southeasterly winds 7-9 kt tonight, becoming southwesterly Thursday afternoon.

JD/MGF

MARINE

A Gale Warning continues this evening for the eastern Strait of Juan de Fuca, Admiralty Inlet, and northern inland waters. Southerly winds will taper off tonight, but remain breezy in these aforementioned areas, as such, a Small Craft Advisory continues tonight. Otherwise, light winds are expected late Thursday through Friday with broad low pressure over the region. Northerly winds develop Saturday and continue into early next week.

Rain showers linger tonight through Thursday. There is a 20 to 30% chance for thunderstorms along the Coastal Waters tonight, with a 10 to 25% chance of thunderstorms for all waters Thursday afternoon.

Seas remain in the 8 to 11 foot range tonight through Thursday morning. Seas further ease to 4 to 6 feet late Thursday through the weekend.

JD/MGF

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Gale Warning until 11 PM PDT this evening for Admiralty Inlet- East Entrance U.S. Waters Strait Of Juan De Fuca-Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory until 11 AM PDT Thursday for Admiralty Inlet-East Entrance U.S. Waters Strait Of Juan De Fuca- Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory until 11 PM PDT this evening for Puget Sound and Hood Canal.

Small Craft Advisory until 11 AM PDT Thursday 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.