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Area forecast discussion 
National Weather Service Eureka California
229 am PST Tuesday Feb 9 2016

Synopsis...above normal temperatures will continue through the
week...with a modest cooling trend by Friday. Rain is likely
across the north Friday and Friday significant
additional precipitation is expected through the weekend.


Discussion...a large...persistent ridge has resulted in
unseasonably warm and dry conditions throughout the West Coast
..with temperatures near and Above All time records in some
places in northwest California. Offshore winds are beginning to
switch to a more southerly along coast direction. This will lead
to a moderating of high temperatures...particularly near the
coast where most locations will see slight cooling over yesterdays
highs that climbed into the upper 70s to near 80. Conditions will
be similar today as yesterday with the exception that the
southeast winds have switched to the south per the profiler at
acv. This southerly direction will limit the down slope warming
affect. This combined with slightly lowering 1000-500 mb
thicknesses...will likely keep temperatures a few degrees cooler
than they were yesterday.

By this evening...the upper ridge will begin a gradual process of
weakening as a longwave trough across the northern Pacific
attempts to move eastward. As this occurs...a series of weakening
frontal boundaries will attempt to move onshore...finally
succeeding in doing so overnight Friday/early Saturday. Though
previous model runs have indicated a greatly diminished trough
moving over the ridge into the Pacific northwest...models are now
indicating that the trough will be strong enough to bring some rain
to the northern sections of the County Warning Area. Have updated the forecast to
indicate likely measurable rain mainly near the Oregon border. While
some light drizzle will be possible near the coast at times prior
to this...late Friday is likely the regions best shot at
measurable precipitation until sometime in the middle of next
week. Beyond Saturday...the upper ridge will quickly reassert
itself across the West Coast...sending the storm track back
northwards into the Pacific northwest. Above normal temperatures
and below normal precipitation will continue to be the story for
the next week. Mkn


Aviation...ridging aloft will promote widespread VFR conditions
across northern California with mostly sunny skies expected through
the early half of the day. Clouds will increase this afternoon and
tonight as a weak disturbance moves over northern California.
Ceilings will remain high and southeasterly winds should prevent the
development of lower ceilings. Visibilities will remain high but
some haze could impact kcec and kacv. Kml


Marine...winds will remain light to moderate through the week as
broad ridging over the western United States maintains a relaxed
pressure gradient across the coastal waters. The sea state will
diminish briefly today before a larger westerly swell builds across
the waters Thursday and Friday bringing the sea state to 12 to 14
feet. Small craft advisories will likely be needed. Furthermore, this
swell will bring a threat for sneaker waves Thursday morning and
afternoon as the rapidly building swell impacts the northwest
California coast. Mariners are advised to avoid fishing near shallow
water Shoals and rocky areas as long period wave systems increase
set behavior in the surf zone which can catch you off guard. Kml


Eka watches/warnings/advisories...
Northwest California coastal waters...none.


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