textproduct: Seattle/Tacoma

SYNOPSIS

A frontal system will continue to move across Western Washington today for lowland rain. Another system will move into Oregon and southern Washington Sunday. Unsettled weather continues early next week with split flow. There will be a brief period of drier weather on Wednesday before additional systems move over the area Thursday and into the weekend.

SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/

The cold front has reached the coastline this evening and will continue to push inland tonight. The latest radar imagery shows rain coverage has decreased this evening, with light scattered showers moving across the region. In addition, winds have also subsided.

Another system will move into Oregon on Sunday but will provide us with another wave of rain throughout the afternoon, turning into some showers by the evening. Snow levels will fall to 3000 to 3500 feet, resulting in some light accumulations in the mountains, including the passes. Temperatures will also slightly cool in the upper 40s.

Weak troughing will continue over the area on Monday, with unsettled conditions, but lingering shower activity will continue with temperatures in the upper 40s.

LONG TERM /TUESDAY THROUGH SATURDAY/

Ensembles continue to show a split flow pattern Tuesday into Wednesday, keeping conditions mostly dry over western Washington as most of the energy continues to be aimed towards California. Weak ridging looks to build somewhat on Wednesday, for areas of fog and stratus likely in the morning. Temperatures continue to remain in the upper 40s and lower 50s. Active weather will return on Thursday and into the weekend as ensembles show multiple systems approaching western Washington.

Mazurkiewicz/29

AVIATION

FROPA has resulted in a mixed bag of cigs across W WA this evening. While the majority of obs sites continue to report MVFR to IFR conditions, there are spots in the SE Sound, the Islands and along the Strait reporting low end VFR conditions. As rain transitions to showers overnight and low level moisture becomes widespread and dominant, widespread MVFR to IFR conditions are expected to persist tonight into Sunday morning. A break in activity will allow for widespread VFR conditions to return to the area by late Sunday morning/early Sunday afternoon and persist for much of the remainder of the TAF period. Locations more prone to lower cigs and fog, such as PWT and OLM, may see MVFR to IFR conditions return Sunday evening. Southerly winds remain gusty over much of the area this evening, but some terminals are starting to hint at speeds starting to ease. Generally light and variable winds are still expected to emerge overnight.

KSEA...Cigs this evening shifting back and forth from low-end VFR to high-end MVFR /approx 2500-3000 ft/. As the front continues to shift eastward, lingering low level moisture should be sufficient to allow cigs to lower into more convincing MVFR conditions overnight and remain that way until mid-morning Sunday...after such time VFR conditions should return. Southerly winds still in the 10-15 kt range as of this writing and while the forecast trend still shows winds easing tonight and through the overnight hours, timing will likely be the main issue for the 06Z issuance. Light and variable winds turning more northerly in the late morning and early afternoon with speeds remaining 5 kts or less. A shift to southerly winds again late in the TAF period while speeds remain low.

18

MARINE

A frontal system has exited most of the waters. A nominal push of westerlies down the Strait of Juan de Fuca will keep small craft advisory headlines going for the central and east Strait into tonight. Otherwise, winds will ease area-wide. Seas will remain elevated in the 9 to 12 foot range this evening then come down into early Sunday morning over the coastal waters.

A few additional weak systems move through the region Sunday and Monday, while winds look to remain below advisory thresholds elevated seas in the 9 to 12 foot range are forecast to move back into the coastal waters. Broad high pressure begins to set up on Tuesday through mid-week for more tranquil conditions. The next more significant system looks to arrive by the end of the week.

KC/18

HYDROLOGY

Heavier precipitation over the weekend will force rises on the Skokomish River in Mason County over the weekend with the river continuing to remain close to minor flood stage on Sunday. Flooding is not expected elsewhere over the next 7 days.

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until midnight PST tonight for Central U.S. Waters Strait Of Juan De Fuca-East Entrance U.S. Waters Strait Of Juan De Fuca-Grays Harbor Bar.

Small Craft Advisory until 4 AM PST Sunday 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.