082
FXUS66 KEKA 152300
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
400 PM PDT Wed May 15 2024

.SYNOPSIS...A summer-like weather pattern will persist through the
week with hot and dry afternoons in the interior and low clouds and
fog along the coast. Cooler interior temperatures are forecast for
the weekend and early to mid next week.

&&

.DISCUSSION...Stratus and fog remained bottled up from about Cape
Town southward today. Marine layer has remained shallow with low
clouds confined to much of the immediate coastline of SW Humboldt
and Mendocino Counties. Time-height sections show a deeper humid
layer developing over the Humboldt Bay area tonight and expect low
clouds and fog to form and spread into Eel delta. Stratus and fog
will most likely linger over coastal areas through the day on Thu.

Statistical guidance indicates 1/4SM vsby`s in fog as far north
as the Del Norte coast late tonight where the strongest E-NE
winds aloft are forecast to occur. Confidence is not high there
will be any stratus or fog as far north as the Del Norte coast,
but shallow fog did occur last night at CEC once the northerlies
decoupled.

Otherwise, skies will remain clear with above normal temperatures
across the interior through the remainder of the week. Interior
temperatures are forecast to trend down as a transient shortwave
trough moves into the Pac NW Thu into Fri. Some coastal drizzle
is certainly possible (10% chance) Thu night. HREF 75th and 90th
percentiles indicate a few hundredths around the Humboldt bay area
by early Friday morning. For now will hold off on adding drizzle
to the forecast.

Additional short wave troughs will knock down the ridge over the
weekend for a continued downward trend of high temperatures. The
rate of decrease and the magnitude of "cooling" are not completely
certain. NBM probabilities for 80F or more for our warmest interior
valleys are still around 60-80% (mostly Trinity, Mendocino and
Lake), but no more than 10% for 90F or more. There are indications
for breezier or windier conditions over the weekend and again
early to mid next week.

A deeper trough is forecast to develop early to mid next week.
Near or below normal interior temperatures are likely (>60% chance).
Probabilities for early morning temps 36F or less increase to
30-50% for some of the valleys of Trinity and 10-20% for some of
the interior valleys of Humboldt, northern Mendo, northern Lake
and Del Norte. Early morning frost in late May? Some light precip
is also possible around mid week with NBM probabilities for > 0.10in
in 24 hours around 10-20%. In short, cooler temps and perhaps some
mountain showers are in store for early to mid next week. DB

&&

.AVIATION...VFR conditions are finally prevailing at all the
terminals early this afternoon. Northerly winds continue to gust to
nearly 30 knots at CEC, which will begin to subside after sunset.
Stratus is off the Mendocino coast and is likely to move northward
overnight, bringing IFR to LIFR conditions to the coast into the
early morning hours. Fog will begin to lift by mid morning as solar
radiation increases. Inland, conditions are expected to stay VFR with
mostly clear skies and light winds. JB

&&

.MARINE...Northerly gales are expected to continue for much of the
week. Along with these gales, a very steep sea state continues for
much of the area, with some relief in the inner waters south of Cape
Mendocino. Waves will continue to be steep for much of the week as
gusty northerlies continue. Friday night into Saturday, gales become
more widespread across most the waters. While winds will peak
Saturday, winds will remain at gales or near-gales through the early
week. Seas will remain steep and elevated through the early week as
well, with combined wave heights reaching over 17 feet in the outer
waters over the weekend. JB

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Hazardous Seas Warning until 9 AM PDT Thursday for PZZ450.

     Gale Warning until 11 PM PDT Friday for PZZ470.

     Hazardous Seas Warning until 3 AM PDT Friday for PZZ475.

&&

$$

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