textproduct: Seattle/Tacoma

SYNOPSIS

A brief break in the weather this afternoon with some showers around. Multiple systems look to cross over the area through Tuesday, bringing rounds of widespread lowland rain, gusty winds, and high elevation mountain snow. Active weather continues through the end of the week with additional systems passing into the area.

UPDATE

We're in between disturbances here across western Washington as transient ridging builds overhead. Mostly dry conditions are favored tonight as mid-high level cloud coverage streams in ahead of the next frontal system. With abundant surface moisture from recent rainfall, areas of fog are set to develop with aid of light surface winds due to weak gradients. Overnight lows will range between the upper 30s to mid 40s.

SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/

Recent radar imagery shows some scattered showers across the Northern Interior and Cascades. Expect this trend to continue throughout the evening hours, with a slight chance (10-20%) of thunderstorms north of Everett. An upper level ridge will move through the area tonight, with drying overnight. Another frontal system will start to move over the area by Monday morning, with rain reaching the coast by the afternoon. Rain will slowly move through the interior by the late afternoon and early evening hours. Additionally, southerly winds will increase once again, with widespread gusts of 20 to 30 mph possible at times throughout much of the area (less strong than the previous days wind). Areas along the coast and Whidbey Island could see gusts up to 35 mph. High temperatures in the mid to upper 50s.

Heading into Tuesday, a long fetch of moisture being aimed at Vancouver Island slightly moves down through western Washington. We'll see another round of widespread rain, with a bulk of the QPF being aimed right at the coast and the Olympic Peninsula. Southerly winds will increase in the afternoon and be slightly stronger than Mondays, with widespread gusts of 35 to 45 mph along the coast, and areas Whidbey Island northward. Rain and wind will continue into Wednesday morning.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Upper level troughing continues Wednesday into Thursday for some scattered shower activity over the region, keeping conditions unsettled. Additionally, minor coastal flooding may be possible on Wednesday morning due to high astronomical tides, primarily along the shorelines of San Juans and Whatcom county. High temps warm up slightly on Wednesday, in the low 60s.

Latest ensemble guidance shows an upper level low around BC that is funneling a plume of moisture towards BC and western Washington Friday into Saturday. At this time, looks like active weather will continue, with widespread rain and breezy winds into the weekend. We'll continue to monitor this system as it gets closer.

Mazurkiewicz

AVIATION

Generally VFR conditions with variable mid and high clouds over the region tonight, though a few patches of fog have developed right after sunset around KOLM and KCLM. Expect increasing mid clouds to inhibit cooling a bit, but given recent rains this may not be enough to preclude fog development or persistence in areas where winds remain light. Any fog that develops likely brings IFR conditions through early Monday morning. The next front then approaches later Monday with heavier rain lowering ceilings and visibility and gusty winds. Expect the line to reach the coast around 20z and into the interior toward 22z. Gusts to 25 kt can be expected as the system moves through.

KSEA...VFR conditions will persist through Monday morning at the terminal. Light winds overnight, becoming easterly. Expect stronger southeast winds to increase around 22z with gusts to 20 kt and the return of rain brining likely MVFR conditions as the front approaches by 00z.

MARINE

High pressure building back over the area this evening will bring a brief period of calmer winds to the waters through late tonight. The next frontal system will move across the coastal waters on Monday, with winds starting to increase across the coastal waters again by early Monday morning and across the interior waters by late morning. Winds will peak in the afternoon, before easing Monday night. Gale warnings are in effect for the Coastal Waters and the Eastern Strait, where probabilities continue to highlight roughly a 60-80% chance of gusts reaching 34 kt. Elsewhere, southerly winds will be breezy, with winds gusting to small craft strength through the afternoon and early evening. There will be a brief lull in winds on Monday night, before another system moves into the region on Tuesday and brings a stronger round of southerlies to the area waters and likely another round of widespread headlines. The weather will remain active through the end of the week as additional frontal systems move through the waters.

Seas between 19-24 ft this afternoon will gradually subside towards 10-12 ft on Monday before the next system brings seas back to the 16-18 ft range on Tuesday. Seas will largely remain above 13 ft through much of the week. The next best chance for seas to build to 20 ft will be by next weekend, with the GEFS highlighting a 30-40% chance of seas exceeding 20 ft off the Washington coast.

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HYDROLOGY

River flooding is not expected the next seven days. Multiple weather systems moving through the area in the next week. While current precipitation forecasts are not expected to cause flooding, this will saturate soils and raise base flows. If the atmospheric river stalls over the area late next week into next weekend we might need to keep an eye on our old friend the Skokomish River. Felton

SEW WATCHES/WARNINGS/ADVISORIES

WA...High Surf Warning until 10 PM PST this evening for Grays Harbor County Coast-Northern Washington Coast.

PZ...Small Craft Advisory until 4 PM PST Monday for Grays Harbor Bar-West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning from 10 AM to 10 PM PST Monday for East Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 10 AM to 10 PM PST Monday for Admiralty Inlet-Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory from 1 PM Monday to 4 AM PST Tuesday for Puget Sound and Hood Canal.

Small Craft Advisory until 4 AM PST Monday 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 4 AM to 7 PM PST Monday 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.