textproduct: Eureka

SYNOPSIS

Light rain continues overnight into Thursday morning and will taper off by the afternoon. Drier conditions expected towards the end of the week.

DISCUSSION

Post frontal conditions, with some weak lingering instability continues the light rain regime through late Wednesday night into Thursday morning. Likely to cease by Thursday afternoon with a few tenths of accumulation as light smatterings of rain fizzle out. Most of the residual rainfall will be in Del Norte and northern Humboldt.

A lobe of high pressure will gradually build over the area through the end of the week. This will bringing generally clear skies and steadily warming conditions, especially for the interior. Highs will likely crest near their highest of the spring so far. Most interior valleys will see highs in the mid 70s with a 15% chance of some highs over 80 in Lake and southern Mendocino Counties.

For the coast, conditions will dry through the week. High pressure will encourage a weak marine layer to form each night, but increasingly strong north winds during the day will encourage quick clearing each afternoon. Gusty north winds pushing close to shore will most likely bring some gusts close to 20 kts each afternoon near shore and locally higher gusts on ridges. There is high confidence that slightly cooler temperatures will return by early next week as high pressure weakens, but there is little chance of wetting rain until late next week at least when about 20% of ensemble models show a weak trough crossing the area. /JHW /EYS

AVIATION...(06z TAFS)

VFR conditions are expected to prevail tonight into Thu. Occasional MVFR ceilings 1500-2500 ft and brief vsby's from 3 to 5SM in moderate to heavy showers may continue this evening for KACV and KCEC. Conditions have been stabilizing and shower activity will wane overnight. Gusty N-NW winds in the first 1000-3000 ft AGL will continue overnight in the wake of the cold front. Prospects for low level wind shear and/or shallow turbulence will continue for the remainder of tonight into perhaps early Thu, primarily across Mendocino and southern Humboldt. This will be particularly hazardous for small and light weight aircraft. LLWS has been added to the KUKI TAF til 05/12Z. Boundary layer mixing will transport higher mountain air down to the surface at forecast terminals on Thu as daytime heating commences and gusty northerly winds are expected by early afternoon at all forecast terminals.

MARINE

A cold air surge will result in gales on Thu for the southern waters and perhaps for the northern waters. Highest coverage, longest duration and greatest chance for gales will be across the southern waters where multiple mesoscale and global models continue to converge on gusts to 35-40 kt. Coverage and duration for gale gusts looks much more scant for the northern waters on Thu. There is a much wider spread amongst the various mesoscale and global models. Forecast confidence is therefore much lower for the northern waters. There still could be some localized accelerations nearshore due the venturi effect. In any case, seas will build to 10-12 feet as short period northerly wind waves combine forces with a short period NW swell and seas will be hazardous for small vessels. Gale force northerly winds and large steep waves will likely continue into Fri, however conditions may ease some Fri night into early Sat. There are signs for another north wind ramp up over the weekend. Strongest winds and largest seas with the weekend storm looks to be over mostly over the outer waters. Winds could end up shifting closer to the inner waters with short period wave propagation into the inner waters. Full gales, near storm force winds and 13-17 ft seas are forecast early next week.

EKA WATCHES/WARNINGS/ADVISORIES

CA... Frost Advisory until 9 AM PST this morning for CAZ110-111- 114.

NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until noon PST today for PZZ450-470.

Gale Warning from noon today to 3 AM PST Friday for PZZ450.

Small Craft Advisory until 7 AM PST this morning for PZZ455- 475.

Gale Warning from 7 AM this morning to 10 PM PST Friday for PZZ455.

Gale Warning from noon today to 3 AM PST Saturday for PZZ470.

Gale Warning from 7 AM this morning to 10 AM PST Saturday for PZZ475.