textproduct: Seattle/Tacoma

SYNOPSIS

A stronger frontal system will bring gusty winds tonight and Friday. A warm front moves northwards on Saturday for warmer weather. A cold front will bring another round of rain and gusty winds late Saturday into Sunday. The weather pattern remains active moving through next week.

SHORT TERM /TODAY THROUGH SATURDAY/

An upper level trough will cross western WA this morning with isolated shower activity expected (mainly in the Cascades). Otherwise, dry weather this afternoon with temperatures in the 50s.

Tonight, a deep low will shift east into northern B.C. with increasing southerly winds across western WA. Highest winds will be along the coast and in the north interior (north of Everett) - Wind Advisories are in effect. Expect gusts to 40-50 MPH overnight with gusty winds easing late Friday afternoon. Most of the rain will be over the Olympic Peninsula and near the Canadian border tonight through Friday. The Seattle metro will see rain late Friday afternoon or evening and continuing Friday night as the cold front shifts SE through the area.

Another deep low will track towards B.C. on Saturday but we will start the day dry as we sit in the warm sector. Highs on Saturday will be warmer and in the 60s. But as the low shifts closer, we will see another round of windy weather across much of western WA. The peak windy period will be Saturday evening through early Sunday morning. Per NBM guidance, there's a 50 percent chance of seeing gusts 50 MPH or greater along the coast and north interior during this period. 33

LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/

Active weather continues through next week as the parade of storms impact the Pac NW. There's little break in the action and each storm brings the potential for gusty winds, additional lowland rain, and high elevation snow. A larger swell train may reach the coast Saturday night or Sunday with the potential for 20 ft seas affecting the coast. 33

AVIATION

West to northwest flow aloft will continue across Western Washington today with post-frontal shower activity winding down. Ceilings will be a mixed bag of VFR and MVFR ceilings this morning as well as a few pockets of IFR across parts of the Southwest Interior and Kitsap Peninsula. Improvement to VFR is expected for most areas toward 18Z as mid and high level clouds associated with a warm front offshore begin to thicken across the region. Ceilings will fall to MVFR late tonight and early Friday across portions of the Olympic Peninsula and North Interior as precipitation associated with the warm front spreads onshore. Gusty east to southeasterly surface winds will develop late tonight into Friday across portions of the coast and North Interior.

KSEA...Periods of MVFR will continue into mid-morning with shower activity diminishing. VFR conditions under varying amounts of high and mid level clouds are expected from 18Z onward into this evening. Surface winds southerly 8 to 11 knots easing this afternoon.

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MARINE

An active period of weather across area waters is expected into early next week as a series of frontal systems cross the region. Winds will increase across the coastal waters, strait entrances, and northern inland waters later tonight into Friday as a warm front approaches the coastal waters and stalls. This system will shift onshore and weaken Friday night as an associated surface low makes landfall near the south end of Haida Gwaii. A complex and much deeper area of low pressure will lift northeastward offshore on Saturday night pushing a vigorous frontal system into the area. If models maintain their current trends, this system will likely generate gales across all area waters along with coastal seas easily crossing the 20 foot threshold.

High pressure may briefly rebuild across the waters Sunday night into early Monday before another front arrives with the renewed potential for additional headlines.

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HYDROLOGY

River flooding is not expected through the next seven days. However, a series of increasingly wet weather systems will bring rain (and high mountain snow) to the region, especially from Friday onward. While current forecasts are not expected to cause flooding, this will begin to saturate soils and raise base flows that could bring a concern with subsequent storms systems into next week.

SEW WATCHES/WARNINGS/ADVISORIES

WA...Wind Advisory from 4 AM to 4 PM PST Friday for Island County- Lowlands of Western Skagit and Northwestern Snohomish Counties-Lowlands of Western Whatcom County-San Juan County.

Wind Advisory from 1 AM to 1 PM PST Friday for Northern Washington Coast.

Wind Advisory from 7 AM to 4 PM PST Friday for Grays Harbor County Coast.

PZ...Small Craft Advisory from 7 PM this evening to 7 AM PST Saturday for Grays Harbor Bar.

Gale Warning from 4 PM this afternoon to 2 PM PST Friday for West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning from 10 PM this evening to 2 PM PST Friday for East Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning from 2 AM to 2 PM PST Friday for Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory from 4 PM this afternoon to 4 PM PST Friday for Admiralty Inlet.

Small Craft Advisory until 10 PM PST this evening 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.

Gale Warning from 10 PM this evening to 4 PM PST Friday 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.