Marine Weather and Tide Forecast for Bayview, CA

DISCUSSION
Deep marine layer conditions persisted across the areas today, particularly across Mendocino county where the top of the layer was up to 3000 feet this morning. Layer was not as deep north Cape Mendo, probably no more than 2000 ft based on web cameras. Extensive cloud cover has been slowly eroding through the day with daytime heating and mixing, but solid cloud cover was still quite persistent and extensive along/offshore the Mendocino coast, adjacent coastal river valleys and SW Mendocino interior.
Based on satellite imagery, trends and BUFKIT RH time-height sections, beefed up the cloud cover for these area. Not sure about the precip chances with cumulus clouds sprouting up with daytime heating over Lake and SE interior Mendocino county. A few sprinkles seem possible through 5 PM today.

Southerly winds associated with meso-scale eddies offshore will probably induce another inland push of low clouds into the Mendo interior tonight. High resolution models have not been resolving these finer scale eddies, however adiabatic warming should reduce the depth of the humid layer by early Friday morning. Offshore flow later tonight will not be sufficient to remove or clear out the stratus.

Interior temps are forecast to generally warm above normal through the weekend into early next week. Average highs for mid April range from 66-72F in the interior valleys with average lows from 37-44F.
Forecast is for highs in the mid 70's to lower 80's and for lows mostly in the mid 40's. A few colder valley sites are forecast to dip down to 36-39F by Sunday and/or Monday, but this not too unusual for this time of year for places like Hayfork, Ruth and Dinsmore.

Models continue to show a cold front and shortwave trough skirting across the Pac NW on Sat with limited precip potential for NW California. Half a dozen or so ECMWF ensemble members do indicate light spotty precip with 24 hour probs <20% for 0.01in. GEFS and CMCE are much lower with 24hr chances near 0%. Thus, precip concerns for this weekend are quite low or non-existent.

Northerly winds will ramp up behind the first shortwave trough with increasing probs for gusts to 40 mph or more over coastal headlands into Sun and Mon. Downscaled ECMWF ensemble and EC EFI have been indicating higher than "normal" northerly winds. EC ensemble mean indicates peak gust up to 40 mph for coastal headlands.
Winds elsewhere are not forecast to be as strong along the coast, generally around 25-35 mph. It will be windy again this weekend, though winds in some of the wind sheltered coastal valleys probably will be lighter. Additional shortwave troughs in the westerlies aloft will follow Sun-Mon and will serve to reinforce the blustery and windy coastal northerlies. Precip probs remain low even into mid week as a deeper trough digs in from the NW. 24 hour ensemble cluster means show a potential for a somewhat wetter scenario mid week. All this may end up amounting to is a few showers over the mountains.

It will get much more interesting toward the latter portion of the week into next weekend (Thu-Sat) with 40% of 2 ensemble clusters depicting a wetter scenario than the ensemble mean. 24-hr probs for half an inch or more increases Fri-Sat with EC ensemble around 30-50% for Del Norte/Humbodlt and 10-30% for Lake, Mendocino and Trinity. NBM is not that bold with 0-5% for SERN Lake to 15-25% for Del Norte. Stay tuned as 500mb cold core may also create a favorable environment for storms and locally heavier precip amounts. DB

AVIATION
A deep marine layer blanketed the North Coast and Mendocino/Lake Counties...and for note, the SF Bay Area. MVFR Cigs were 1000-1800 ft. However, the marine layer was really prolific over Mendocino with tops reaching above 3500 ft. Those heights were unusually well above the near coastal mountain peaks...which allowed clouds to spill into the Ukiah Valley.
Stratus clouds began pulling back towards the coastlines after 1200 noon. CEC cleared early but south winds associated with a faintly spotted offshore eddy, pumped a few thin stratus clouds back into the airport. Overnight, some model guidances are showing a lack of confidence in stratus development especially as high pressure could reduce extent and amount of clouds...and due to some increasing offshore Flow (particularly at CEC). However, ACV and Humboldt Bay will mostly likely see a more shallower marine layer overnight. Inland: The depth of the marine layer may be quite reduced, but a push northward may result in some morning low Cigs at UKI's airport. /TA

MARINE
Strong winds have pushed further offshore and diminished as a high pressure ridge builds into the PNW. Winds and seas in the inner waters will continue to diminish through Friday, with waves as low as 4 to 6 feet and light northerly breezes. Fresh to strong breezes will likely persist in the northern outer waters through Friday before widespread strong northerlies return this weekend. A weak shortwave and dry surface front will help push these winds into the inner waters beginning Saturday afternoon. NBM has 50 to 75% chance for gale gusts 35 to 45 knots in the outer waters through the weekend, including lee and nearshore of Point Saint George and Cape Mendocino. Near-gale to sustained gale force winds and gusts exceeding 40 knots are likely to continue into early next week, making daily diurnal pushes into the inner waters.

EKA WATCHES/WARNINGS/ADVISORIES
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
None.