textproduct: Seattle/Tacoma

SYNOPSIS

An atmospheric river will produce periods of moderate to heavy rain through Monday night. This rain, along with high snow levels, will bring rises on many area rivers. Flooding is expected on the Skokomish River. Strong high pressure then builds into the region by the middle of the week, bringing a stretch of dry conditions.

SHORT TERM /TODAY THROUGH TUESDAY/

Periods of moderate to heavy rain with snow levels above the passes will continue today into Monday as the axis of an atmospheric river settles over the CWA. Heaviest precip is expected in the Olympics and the north/central Cascades. Rises are expected on the rivers with the Skokomish expected to reach flood stage later today. More detail can be found in the hydrology discussion section.

Breezy to locally windy conditions will continue into tonight. The windiest period looks to be late this afternoon into tonight...with gusts of 35 to 45 mph for the North Interior and coastal areas. Wet conditions continue into Monday with the axis of heaviest precipitation expected across the northern half of the forecast area. A drying trend will commence Monday night into Tuesday as upper ridging builds in from the south and shoves the moisture up into British Columbia. As is typical with mild atmospheric rivers, temperatures will remain several degrees above seasonal averages. Near record high temperatures are possible on Tuesday.

LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/

Models dissipate a front as it approaches the area on Wednesday and bumps up against 500 millibar heights in the 575 to 580 decameter range. High amplitude ridging then builds just offshore for the remainder of the week for dry conditions. 27

AVIATION

Frontal boundary stalled over the northern portion of the area through Monday. Southwesterly flow aloft becoming westerly tonight. Southeasterly flow in the lower levels.

VFR ceilings over the interior with MVFR along the coast and Kitsap Peninsula. Areas of LIFR continue to linger along the Strait of Juan de Fuca. Scattered showers continue this morning. Expect reduced visibility to 3-5SM in rain. Ceilings lowering over the interior to MVFR later tonight continuing into Monday. S/SE winds will pick up this evening to 8-15 kt. The strongest winds will be along the coast and PAE northwards, where gusts 25-30 kt are likely.

KSEA...VFR ceilings lowering to MVFR after 03z Monday. Visibility around 3-5SM in rain at times. S/SE wind this morning 4-7 kt will increase this evening to 8-12 kt. Felton/29

MARINE

A front over the northern portion of the waters will remain stationary into Monday. The front will lift north Monday night or early Tuesday as high pressure rebuilds over the waters. High pressure remains in place through the remainder of next week.

Small craft advisory conditions today increasing to gales tonight then easing back to small craft advisory Monday for the coastal waters, Entrances to the Strait, Admiralty Inlet and the Northern Inland waters. Winds increasing to small craft advisory speeds tonight for Puget Sound and Hood Canal. Winds easing all areas Monday night into Tuesday. Light winds over the waters Tuesday night through Thursday.

Seas 12 to 18 feet today building to 14 to 19 feet tonight. Seas subsiding to 12 to 15 feet Monday and to 9 to 12 feet Monday night. Seas remaining in the 9 to 12 foot range Tuesday and Wednesday before subsiding again to 6 to 8 feet Thursday.

HYDROLOGY

The Skokomish River continues to rise, and it is expected to reach flood stage later today before cresting just above moderate flood stage Monday morning.

With the heaviest rainfall still aligned across the Olympics and the North Cascades, these areas will continue to see the highest potential for flooding. The next surge of moisture arrives late this evening, and storm totals are expected to peak in the 3 to 5 inch range with snow levels holding high near 7000 ft.

SEW WATCHES/WARNINGS/ADVISORIES

WA...None. PZ...Small Craft Advisory until 6 PM PST Monday for Grays Harbor Bar.

Small Craft Advisory until 6 PM PST this evening for Admiralty Inlet-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- East Entrance U.S. Waters Strait Of Juan De Fuca-Northern Inland Waters Including The San Juan Islands-West Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 6 AM to 6 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-West Entrance U.S. Waters Strait Of Juan De Fuca.

Gale Warning from 6 PM this evening to 6 AM PST Monday for Admiralty Inlet-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-East Entrance U.S. Waters Strait Of Juan De Fuca-Northern Inland Waters Including The San Juan Islands-West Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 6 AM to 1 PM PST Monday for Admiralty Inlet-East Entrance U.S. Waters Strait Of Juan De Fuca-Northern Inland Waters Including The San Juan Islands.

Small Craft Advisory from midnight tonight to 6 AM PST Monday for Puget Sound and Hood Canal.