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Area forecast discussion 
National Weather Service Eureka California
322 PM PST Thursday Feb 11 2016

Synopsis...mostly dry and warm conditions will continue through
Tuesday...with the exception of periods of light rain Friday and
Sunday in areas north of Cape Mendocino. Chances for more
significant rain and a return of colder temperatures are expected
by the middle of next week.


Discussion...after a diffuse warm front brought some very light
showers to a few places near the coast overnight...skies have
mostly cleared throughout the region aside from a stubborn region
of marine stratus/fog that has plagued a few locations along the
Mendocino coast. This has resulted in a warm...pleasant day
throughout the region...with temperatures once again climbing into
the 60s and 70s. Meanwhile...a rather unimpressive cold front
continues to creep closer to shore...along with increasing cloud
cover that will begin to invade inland areas later this evening.
While latest indications are that this front may be arriving a bit
slower than previously thought...the implications remain generally
the same as areas north of Cape Mendocino will likely see a period
of light rain from tomorrow morning through sometime in the
afternoon. Precipitation totals will be rather meager...with
accumulations of around a quarter of an inch in parts of del Norte likely only a few hundredths in southern Humboldt
County and perhaps the mountains of western and northern Trinity
County. After a a dry day Saturday...a passing shortwave will
traverse the top of the ridge to our north on Sunday...likely
bringing another glancing shot of light rain to areas north of
Cape Mendocino with a focus across del Norte County.

By Monday...the ridge will re-assert itself across the West
Coast...resulting in warm and dry conditions once again Monday and
Tuesday. By Wednesday though...this persistent West Coast ridge
will finally begin to break down more completely...allowing the
return of cold winter storm systems from the northwest. The exact timing
and nature of the first storm system remains somewhat uncertain
given a fairly substantial spread amongst ensemble
well as disagreement amongst the major deterministic model runs.
Regardless...there is a strong signal for the return of
precipitation and lowering snow levels by the middle of the
week...which justifies the inclusion of likely precipitation
probabilities Wednesday and chance probabilities thereafter. /Brc


Aviation...a weakening frontal boundary will bring lowering
ceilings and visibilities to the coastal airfields late tonight and
through the day on Friday. Confidence is moderate that both kacv
and kcec will see MVFR conditions during this 00z taf
cycle...however the exact timing is not. Conditions may drop to
IFR for a brief time in light rain during the morning Friday as
the front washes out along the north coast. Conditions may not
improve much Friday night either as low level moist air gets trapped
along the coast. Ukiah should remain VFR with only middle
clouds...though light mist may develop briefly early Friday morning.


Marine...long period westerly swell will continue to build across
the waters tonight...with heights reaching 12 to 14 feet by early
Friday morning. The primary concern tonight into early Friday
continues to be the potential for "sneaker waves" and above normal
wave run up at the beaches. The swell will remain moderately high
through Friday night before gradually subsiding over the weekend.
Even though we have issued a Small Craft Advisory for the long
period swell...wave steepness will likely remain average through
Saturday. Short period northerly wave generation is expected south
of cape mendo over the weekend and waves should become steeper as
the swell heights subside and swell periods decrease. The duration
and strength of the northerlies will probably limit short period
wave growth...with only 2 to 4 feet wind waves expected at this


Eka watches/warnings/advisories...
Northwest California coastal waters...
Small Craft Advisory until 3 am PST Sunday
for pzz450-455-470-475.



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