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Area forecast discussion 
National Weather Service Eureka California
1119 am PDT Sat Aug 30 2014

Synopsis...warm middle day temperatures along the coast will turn
cooler by late afternoon as onshore flow develops. Temperatures
will continue to warm across the interior with some gusty winds as
an upper trough cuts across northwest California. A general warm and dry
trend will begin on Sunday as high pressure slides over the
region.

&&

Update...quick update to the forecast in order to capture the
quick warming along the coast this late morning. Temperatures along the
coast should peak very early in the afternoon before the afternoon
onshore flow kicks in effectively capping the temperatures. The interior
should continue to warm through much of the day with many areas
reaching deep into the 80s if not the low 90s, especially across
interior Mendocino County. Gusty afternoon winds are still
expected over area ridges. Otherwise, look for generally clear
conditions. Bfg

&&

Previous discussion......issued at 323 am PDT...

Synopsis...an upper level trough will bring a cool down to northwest
California for this weekend. This system will act to deepen the
marine layer which will drive clouds a little farther up the river
valleys tonight. Weak high pressure will build over the
region beginning Sunday into early next week bringing warmer
temperatures.

Discussion...an upper level trough is moving into the Pacific
northwest and will clip northwest California. The primary impact
from this trough will be to cool temperatures back closer to
seasonal normals this weekend. Northwesterly flow aloft will develop
this afternoon allowing smoke from the Happy Camp complex to drift
into northern Trinity County through the weekend. The trough will
begin to pull out to the east Sunday leaving a weak pressure
gradient over the area allowing the normal overnight offshore flow
to return. Thus smoke will likely also drift south toward Orleans
and possible Willow Creek Sunday night and also possibly late
Saturday night/Sunday morning.

Upper level ridging will build off the West Coast on Monday into
Tuesday bringing a warmup back to interior areas with highs back
into the middle and upper 90s. Temperatures along the coast will
continue to be held in the 60s with low clouds and fog a concern
each night/day. Th ridge will also turn winds aloft back out of
the southeast causing the smoke to move back northeast out of the
area through at least midweek.

By midweek another upper trough will dig toward the Pacific northwest and
northwest California. Models are showing that this trough will pick
up whatever is left of tropical system Marie and shift it toward the
coast. Models are not indicating any precipitation with this trough late in
the week. However, the remnants of a tropical system can often bring
decent moisture to an unstable trough as it is swept up into the
extra-tropical flow. Uncertainty is high with any precipitation or
convection developing late in the week, but it will be something to
watch. Uncertainty encompasses potential occurrence, timing, and
location. As such, have left probability of precipitation below any mentionable amounts for
now. Otherwise, continue to expect fair conditions across the
interior with more low clouds and fog at the coast. Bfg/rpa

Aviation...IFR to LIFR conditions and light winds to calm
conditions will continue at kcec through the early morning.
MVFR to LIFR conditions will occur at kacv through the early
morning. The lower conditions at kcec and kacv are due to reduced
ceilings and/or visibilities due to patchy fog and/or stratus
occurring across some coastal areas. IFR to VFR conditions will
prevail at kcec and kacv this afternoon with light to moderate
winds. VFR conditions and light winds to calm conditions will
continue at kuki through this weekend.

Marine...an offshore high pressure ridge and inland thermal low
pressure trough will strengthen the next few days. The interaction
between these two systems will gradually increase the pressure
gradient across the waters this weekend and early next week.
Subsequently northerly winds and the seas will gradually increase
the next few days and early next week. Winds and seas will be higher
across the outer waters early next week. A Small Craft Advisory
remains in effect across the southern outer waters and it will
be necessary to extend small craft advisories across the northern
outer waters early next week due to increasing winds and seas. Small
craft advisories are likely across the near shore waters early next
week due to increasing seas.

&&

Eka watches/warnings/advisories...
California...none.
Northwest California coastal waters...Small Craft Advisory until 3 PM PDT Tuesday pzz475.

&&

$$

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