Central U.S. Waters Strait of Juan de Fuca Marine Forecast
|Today...W Wind 5 To 15 Kt Becoming To 10 Kt In The Afternoon. Wind Waves 2 Ft Or Less. A Chance Of Showers In The Morning.|
|Tonight...Se Wind 5 To 15 Kt Becoming E 15 To 25 Kt After Midnight. Wind Waves 2 Ft Or Less Building To 2 To 4 Ft After Midnight. A Slight Chance Of Rain After Midnight.|
|Sat...E Wind 15 To 25 Kt Rising To 20 To 30 Kt In The Afternoon. Wind Waves 3 To 5 Ft. Rain.|
|Sat Night...E Wind 15 To 25 Kt Easing To 5 To 15 Kt After Midnight. Wind Waves 2 To 4 Ft Subsiding To 2 Ft Or Less After Midnight.|
|Sun...Se Wind 10 To 20 Kt Becoming E 5 To 15 Kt In The Afternoon. Wind Waves 1 To 3 Ft.|
|Sun Night...Ne Wind 5 To 15 Kt. Wind Waves 2 Ft Or Less.|
|Mon...Ne Wind 5 To 15 Kt Becoming E To 10 Kt. Wind Waves 2 Ft Or Less.|
|Tue...E Wind To 10 Kt. Wind Waves 1 Ft Or Less.|
| Area Forecast Discussion|
National Weather Service Seattle WA
928am PST Fri Dec 8 2023
Showers will continue to taper through the morning for a brief lull in the active weather this afternoon and evening. The next vigorous system will move into the region Saturday into Sunday and will bring moderate to heavy rain, mountain snow, and areas of gusty winds. A quieter period of weather is expected early next week as upper level ridging moves back into the region.
Short Term - Today through Sunday
Winter Weather Advisory has been extended for the central Cascades with a convergence zone aimed near Stevens Pass. Otherwise, snowfall has mostly ended for the Cascades including Snoqualmie Pass. 33
Previous discussion...Scattered showers continue early this morning, with latest MRMS radar showing the heaviest showers currently moving inland along the coast. Snow continues to fall in the mountains, with latest observations indicating that Stevens Pass has picked up roughly 7 inches since this afternoon and Snoqualmie Pass has picked up roughly 6 inches. The latest runs of the hi-res guidance still hint at a Puget Sound Convergence Zone developing across the central Sound for a few hours early this morning. A few more inches of snow could fall along the passes should the PSCZ develop and position itself along the US-2 or I-90 corridor. Thus, a Winter Weather Advisory remains in effect through mid morning.
Overall, expect to see showers taper through the morning hours today. Drier conditions are expected across western Washington this afternoon and evening as a shortwave ridge traverses the region. Afternoon highs will be in the mid to upper 40s across the forecast area.
The break in the active weather will be rather short-lived as the next vigorous system moves into the region Saturday into Sunday. This system will bring another round of lowland rain, mountain snow, and gusty winds to the area. Moderate to heavy rainfall will be possible at times, with amounts generally ranging from 0.75-2 inches across the interior lowlands to 2-3 inches for areas along the coast. Snow levels will start out below pass level, but look to rise to 5000-6000 feet by early Sunday. Moderate to heavy snow will be possible in the mountains through early Sunday, with the latest probabilistic data showing roughly a 70-90 percent chance of snowfall exceeding a rate of 1 inch per hour at times Saturday afternoon and evening. Southerly winds will increase Saturday morning and peak during the mid-day hours before decreasing in the evening. Gusts to 45 mph will be possible at times for areas along the Pacific coast and from Port Townsend/Whidbey Island northward. In addition to lowland rain, mountain snow, and gusty winds, snow levels rising rapidly on Sunday has led to an increased concern for isolated river flooding. For more details on flooding, see the hydro section below.
Long Term - Monday Through Thursday
Ensembles remain in good agreement with regards to a ridge of high pressure moving into the region early next week for drier and relatively quieter weather for western Washington. The ridge axis looks to move inland by midweek, which could open the door for additional systems to move across the area. There is some indication of a weak upper level trough and its associated surface front approaching the region mid to late week and dissipating over the area as it moves inland. Have kept mention of precipitation in the forecast from Wednesday onward for now, however, the timing and track of this system will need to be refined in the coming days. 14
A strong low pressure system is moving into the NE Pacific for the weekend, draping a cold front over the area waters. The forecast remains on track for strong southerly winds reaching gale force beginning late tonight through Saturday for the coastal waters. Gales are also likely Saturday for the East Entrance to the Strait of Juan de Fuca and Admiralty Inlet. Therefore, Gale Watches have been issued for the aforementioned locations. Winds will likely reach gale force into the Haro Strait, but have held off issuing a gale watch for the entire Northern Inland Waters zone. Winds will taper off Saturday night and remain benign into next week.
Seas 7 to 9 ft at 12 s today before rising to around 12 to 16 ft though the weekend. Seas will then plummet to 3 to 5 ft by Monday into Tuesday before the next system brings seas back above 10 ft Wednesday.
The Chehalis River continues to drop with Grand Mound now in Action Stage, though Porter remains in Minor Flood Stage. Levels will continue to drop on rivers area-wide today with generally dry conditions after scattered light showers shift east of the area later this morning.
A brief lull in activity today before the next frontal system brings another round of rain and mountain snow. Snow levels start off between 1500 and 2000 ft Saturday then rise to near 7500 ft Saturday night. Forecast rainfall totals range from 3-5 inches to 2.5 to 3.5 inches along the coast and over the Cascades. A combination of rain and snowmelt will lead to rises in river levels, especially with increased sensitivity from recent flooding earlier this week as many rivers are currently in or near Action Stage. There is a low chance (15% or less) of exceeding flood stage on rivers in the outlook areas of Mason, King, Thurston, Grays Harbor, and Lewis Counties. Slightly greater chances for flooding along the Skokomish River in Mason County where a Flood Watch remains in effect through Sunday morning.
NOAA Seattle WA Office: Watches - Warnings - Advisories
WA...Flood Watch through Sunday morning for Hood Canal Area-Lower Chehalis Valley Area-Olympics.
Winter Weather Advisory until 1pm PST this afternoon for West Slopes North Central Cascades and Passes.
PZ...Gale Watch from Saturday morning through Saturday evening for
East Entrance U.S. Waters Strait Of Juan De Fuca.
Gale Watch from late tonight through Saturday 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.