Area Forecast Discussion
Issued by NWS Eureka, CA

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FXUS66 KEKA 292246

National Weather Service Eureka CA
346 PM PDT Sat Apr 29 2017

.SYNOPSIS...A weakening frontal boundary will impact far
northwestern California during Sunday morning, resulting in some
light rain or drizzle for locations north of Fortuna. Dry weather
and moderating temperatures will then prevail over much of the
region during the new work week.


.DISCUSSION...A weak frontal boundary moving by to the north of
the area and squashing down the ridge will bring the chance for
some drizzle or light rain late tonight into Sunday morning. Nam
soundings tend to lean more towards drizzle so will have changed
the forecast to drizzle. Farther south and east there will likely
be some clouds and slightly increased mixing. This should limit
the potential for frost tonight. Sunday afternoon skies are
expected to clear and northerly winds will increase once again.
There will be the potential for frost Sunday night, especially in
Trinity county. Temperatures aloft are similar to this morning
when frost occurred in some of the colder valleys. There may be
some lingering stratus around Humboldt Bay, but this is expected
to clear up fairly quickly Monday morning with some weak offshore

Tuesday high pressure continues to build over the area with the
upper level ridge axis just off the coast. Inland temperatures
will continue to warm and the coast may see some warming, although
the moderate to strong northerly winds will limit that potential.
Tuesday night the frost threat should diminish as temperatures
aloft warm considerably. Wednesday the ridge axis will push past
the coast. Inland this is expected to be the warmest day, however
at the coast the flow is expected to turn more onshore and
temperatures and there is an increased likelihood of coastal
stratus. Thursday the ridge continues to edge off to the east.
This will bring the potential for some showers over Trinity
county with a slight chance for thunderstorms. There is adequate
cape, but the mid level lapse rates are only around 6.5 c/kg and
is often a limiting factor. The gfs shows a trough approaching
the area on Friday and bring showers and cooler weather, although
confidence is low on this. MKK


.MARINE...Persistent offshore high pressure will maintain moderately
breezy northerly winds across the waters through at least the middle
of the week. Winds throughout the region currently range between
around 10 kt in near-shore areas north of Cape Mendocino, to near 25
kt from Cape Mendocino southwards...particularly near the Lost
Coast. This pattern will continue for several days with generally
minor fluctuations, maintaining moderately choppy seas ranging from
around 4 to 6 feet north of the Cape to 6-9 ft south of the Cape.
Towards the end of the work week a weak cold front will pass through
the waters, and as this front passes, even deeper high pressure will
build across the Pacific.  As a result, winds will likely increase
yet again, potentially to near gale strength at times. /BC


.AVIATION...VFR conditions are expected to continue at all
terminals through the early evening. By late evening, shallow
stratus may develop along the coast, with highest confidence near
Humboldt Bay as was seen earlier this morning. Should this early
stratus develop, periodic IFR ceilings will be possible. Later
tonight, a weak cold front will result in widespread lowering
ceilings, and perhaps some drizzle along the coast. The primary
concern with this later activity will be lowering ceilings, as IFR
conditions are likely to develop for a few hours both CEC and ACV
near sunrise. VFR conditions will likely return to the coast by
late morning. VFR conditions are expected at UKI for the next 24
hours. /BRC

    Small Craft Advisory until 5 AM PDT Wednesday for PZZ475.



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