Marine Weather and Tide Forecast for Lacey, WA

SHORT TERM /TODAY THROUGH SUNDAY/
Areas of light rain mainly over the Cascades and northern Olympic Peninsula lingering this morning. Light rain will shift north into British Columbia as upper level ridging begins to move onshore late in the afternoon and evening. The upper level ridge will give the area a need break in precipitation during the day Saturday.

A weak frontal system will bring precipitation back to the area Saturday night into Sunday with a 30-50% chance of 1 to 2 inches of precipitation falling over the Olympics and northern Cascades through Sunday evening. Snow levels are expected to be above 5500 feet through this period and given the antecedent hydrologic conditions throughout the area has the potential to result in impacts to area rivers.

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
Ensembles continue to consistently bring a stronger system back into western Washington quite literally on the heels of the late weekend system. This would return widespread, heavier rainfall to the area as well as windy to gusty conditions for parts of western Washington. Interestingly, long range ensemble clustering does indicate several scenarios associated with differences in the upper level pattern, however each of these patterns result in similar precipitation forecasts over much of the Pacific Northwest - including western Washington. Snow level forecasts remain high - 7,000 to 8,000 feet - for much of Monday, so that the initial push with this system would fall as rain over most of the higher terrain. The National Blend of models is currently showing a 30-60% chance of 3 to 4 inches of precipitation over the Olympic and the Whatcom, Skagit and Snohomish Cascades through Monday evening. If this occurs it would contribute to renewed or prolonged flooding impact to many area rivers. Similarly the NBM showing 80-90% probabilities of wind gusts greater than 45 mph along the coast, and 60-80% odds over the area of Admiralty Inlet to western Whatcom County.

The persistent large scale pattern of broad troughing over the northern Pacific through increases the likelihood of active if not impactful weather through much of the remainder of the week.
This could include periods of widespread rain, high- elevation snow and even winds.

AVIATION
Majority of terminals IFR to LIFR this morning and seeing visibilities generally between 1-3SM. Limited improvement is expected by the afternoon towards MVFR for most terminals. Some guidance is hinting seeing brief improvement towards low-end VFR this evening, but confidence is low at this time. IFR/LIFR conditions expected to return overnight.

KSEA...IFR conditions at the terminal this morning with visibilities as low as 1.50SM. Expecting to see gradual improvement by the afternoon but only to MVFR with ceilings at or below 2500 feet. May potentially see low-end VFR ceilings briefly this evening, but not confident to include in the prevailing line. IFR/LIFR conditions expected to return overnight. Southwesterly surface winds increasing this afternoon to 5-7 kt.

29/27

MARINE
A weak surface ridge will remain over the coastal and interior waters today. The first of a series of fronts will approach the coastal waters late Saturday. A series of vigorous frontal systems will impact area waters early next week with headlines for both winds and hazardous seas.

Seas will climb back into double digits Sunday night into Monday and remain hazardous for the foreseeable future. 27

HYDROLOGY
Many rivers continue to run at significant or near record levels, especially over the western Cascades. Those rivers that are slower to respond, including the Nooksack, Skagit, and Snohomish, will take a few more days to fully crest and lower below flood stage.

* Numerous River Flood Warnings remain in effect across western Washington, with varying times and flood levels.

* A Flash Flood Watch remains in effect for a potential levee failure of the Skagit River below Sedro-Wooley to the mouth of the Skagit River through late Friday.

* A Flood Watch remains in effect through Friday across all of western Washington.

With very wet antecedent soil conditions, the landslide threat across the region has increased with this system, and several landslides and mudslides have already occurred in steep terrain across western Washington. Potential has also increased for debris flows over area burn scars, which continue to be monitored.

While the threat of urban flooding has decreased, the threat of small stream flooding, as well as for areas with poor drainage, continues to pose a risk of localized nuisance flooding and ponding on roadways. Low water crossings may become impacted or impassable.

The latest river observations and forecasts can be found at water.noaa.gov.

33/15



SEW WATCHES/WARNINGS/ADVISORIES
WA...Flood Watch until 4 PM PST this afternoon for Cascades of Pierce and Lewis Counties-Cascades of Snohomish and Northern King Counties-Cascades of Southern King County- Cascades of Whatcom and Skagit Counties-City of Seattle- Downtown Everett / Marysville Area-Eastern Kitsap County- Eastern Strait of Juan de Fuca-Eastside-Foothills and Valleys of Central King County-Foothills and Valleys of Pierce and Southern King Counties-Foothills and Valleys of Snohomish and Northern King Counties-Foothills and Valleys of Thurston and Lewis Counties-Foothills and Valleys of the North Cascades-Foothills of the Western and Southern Olympic Peninsula-Grays Harbor County Coast- Island County-Lake Crescent Area Including US 101-Lower Chehalis River Valley-Lowlands of Lewis and Southern Thurston Counties-Lowlands of Pierce and Southern King Counties-Lowlands of Western Skagit and Northwestern Snohomish Counties-Lowlands of Western Whatcom County- Middle Chehalis River Valley-Northern Hood Canal-Northern Washington Coast-Olympia and Southern Puget Sound- Olympics-Port Townsend Area-San Juan County-Shoreline / Lynnwood / South Everett Area-Southern Hood Canal-Western Strait of Juan de Fuca-Willapa and Black Hills.

Flash Flood Watch through late tonight for Lowlands of Western Skagit and Northwestern Snohomish Counties.

PZ...None.