Marine Weather and Tide Forecast for Onalaska, WA

SHORT TERM /TODAY THROUGH MONDAY/
Area radars look vastly different compared to the last 24 to 48 hours or so. Upper-level ridging is building over the PNW, resulting in drier and more stable conditions for western Washington this weekend. Temperatures this morning range between the upper 30s to mid 40s with patchy fog observed across the Chehalis River valley and the Kitsap Peninsula. Aforementioned will gently progress across the region as its axis centers over the Inland NW by Sunday. Large-scale subsidence will bring milder conditions as highs top out in the upper 50s, to lower 60s. Overnight lows are to bottom out in the 40s.

A weak frontal system will approach the the region Sunday night into Monday and increase precipitation chances. While much of the lowlands will see light amounts less than a tenth or two, the bulk of the moisture will fall over the northwestern Olympic Peninsula and North Cascades, where amounts could reach half an inch or more.



LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
Conditions look to trend drier again for both Tuesday and Wednesday. Ensembles are in agreement on the 500 mb pattern favoring a setup for ridging along the West Coast, shifting eastward over the Intermountain West during this time. Active and wet weather is set to return towards the end of next week, but the exact details remain uncertain.

McMillian

AVIATION
Upper level ridge over Western Washington with the ridge axis shifting east of the area this afternoon. Westerly flow aloft becoming southwesterly this afternoon. Southwesterly flow aloft continuing through Sunday. In the lower levels weak offshore flow through tonight becoming light Sunday.

Satellite imagery shows fog along the I-5 corridor in the Southwest Interior, between Olympia and Hoquiam, near the Hood Canal, over the San Juans and Puget Sound. Just high clouds over the remainder of the area. Fog coverage not increasing much except over the Southwest Interior before sunrise. Fog layer looks shallow with the Black hills sticking out of the fog. Low level offshore flow increasing this morning will help dissipate the fog by midday. High clouds at times through Sunday. Low level offshore flow continuing overnight leading to less fog coverage Sunday morning.

KSEA...Tough call on the fog chances for the terminal this morning. As long as the easterly winds continue this should keep the fog to the west from reaching the terminal. Roof observation at 315 AM skies are crystal clear with no evidence of any fog. This gives confidence that a Lake Washington stratus scenario with the clouds drifting over the terminal later this morning scenario is also not in the works. KOLM-KBLI gradient down to -2.1 mb at 11Z/3 AM. Given all this will keep fog out of the terminal this morning. Northeast to easterly winds into Sunday morning will dry the air mass out reducing the fog chances for Sunday morning as well. Northeast wind 4 to 8 knots becoming easterly after 09z. Felton

MARINE
High pressure over the interior with lower pressure over the coastal waters creating weak offshore flow through the tonight. A splitting front reaches the coastal waters later Sunday dissipating as it moves inland Sunday night. High pressure building over the coastal waters Monday remaining in place Tuesday. Next frontal system approaching the area Wednesday night.

Small craft advisories remain up for the coastal waters this morning for 10 foot seas. Seas subsiding this afternoon but could rebuild to 10 feet later Sunday into Monday.

Increasing offshore flow creating small craft advisory easterlies at the West Entrance to the Strait of Juan de Fuca this afternoon through tonight and in the Central Strait tonight. Felton

HYDROLOGY
Skokomish river dropped below flood stage early Saturday morning and will continue to recede today. Next couple of weather systems to reach the area not producing hydrologically significant rainfall. The next chance for heavy rain is not until the end of next week and no new flooding is expected for the next seven days. Felton

SEW WATCHES/WARNINGS/ADVISORIES
WA...None.
PZ...Small Craft Advisory until noon PST today 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-Grays Harbor Bar.

Small Craft Advisory from 10 AM this morning to 6 AM PST Sunday for West Entrance U.S. Waters Strait Of Juan De Fuca.

Small Craft Advisory from 6 PM this evening to 1 AM PST Sunday for Central U.S. Waters Strait Of Juan De Fuca.