Marine Weather and Tide Forecast for Manila, CA

DISCUSSION
An upper level trough remains circulating in the NE Pacific off the coast of British Columbia today, keeping a weak high pressure in place off the coast of central California. High temperatures are forecast to trend upwards over the next couple of days, with most interior valleys seeing mid to upper 80s to low 90s by Sunday. Breezy afternoon winds are likely along the coastal areas again, with high NBM probabilities for over 20-25 mph peak gusts. The highest gusts remain on ridges and coastal headlands, where gusts above 30 mph are possible. The trough to our northwest will slowly move toward our area, with occasional shortwaves bringing a few high clouds and keeping interior temperatures moderated. The trough moves through Monday, but this continues to look dry. Thunder potential in the interior also is unlikely as instability looks meager.

High pressure builds back in Monday, returning the warming trend to the interior. NBM is showing over 50-60% probabilities for 90's in the warmest interior valleys (eastern Trinity, eastern Mendocino, and southern Lake) by Wednesday. Western Mendocino, including Ukiah, have lower probabilities (~20%) as marine air has a better chance of moderating temperatures. Long-range model clusters are starting to coalesce around a trough digging into our area by Friday.
Precipitation chances remain low as NBM probabilities for at or above 0.01" of precipitation is around 25% over Del Norte for Friday and Saturday. The main impacts are likely to be a cooling trend for temperatures late week into next weekend and enhanced afternoon winds. A few ensemble members do have this progressing as an inside slider type of system, moving to our north and east, which are usually indicative of offshore flow and perhaps gusty winds. This could be a fire weather threat and needs to be watched.



AVIATION
18Z TAFs...VFR conditions prevail. A small band of transient coastal stratus briefly impacted ACV with MVFR CIGs , but that activity cleared out. Northerly winds are gusty this afternoon, particularly at CEC. As the winds ease this evening, the stratus will redevelop around Humboldt Bay and The Eel River.
Expansion into ACV and northerly transport along a coastal eddy to CEC is then probable as early as late tonight, but likely early Sunday morning. A weak shortwave trough will by through early Sunday morning, and soundings show some deepening in the marine layer will occur in response. Ceilings will begin MVFR, with chances for further lowering into IFR levels. Models can sometimes underestimate the deepening effect of shortwaves, but with the weakness of this one the effects may be muted.

Confidence: There is a high chance for MVFR CIGS (increasing to 70% through Sunday morning). Low to moderate chance for lowering to IFR levels (40% for early Sunday morning). If the shortwave has less influence on the marine layer, there is a low chance for ceiling heights to dip below 500 ft (20%).



MARINE
Strong to near gale force gusts are forecast to continue through the weekend, with the strongest winds across the outer waters and southern inner waters. Locally gale force gusts downwind of Cape Mendocino and Point Saint George. The sea state will be largely dominated by steep short period wind waves. A small southerly long period swell around 2-3 feet at 19 to 20 seconds will arrive late Saturday night. Winds are forecast to gradually decrease and retreat to the southern waters early next week.



EKA WATCHES/WARNINGS/ADVISORIES
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
Small Craft Advisory until 11 PM PDT Sunday for PZZ450-455- 470-475.