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Area forecast discussion 
National Weather Service Eureka California
issued by National Weather Service Medford or
144 PM PDT Tuesday Sep 2 2014

Synopsis...dry conditions will continue through at least the end
of the week, possibly into next weekend. Offshore flow will
persist into the middle of the week. The thermal trough will build
north and weak onshore flow will return. The offshore flow will
carry areas of smoke from the Happy Camp complex towards the
coast. Temperatures will remain warm for inland locations this
week. -Petrucelli


Discussion...current visible image shows marine stratus starting
to creep back towards Crescent City. Observations the past few
hours has been showing the stratus going there, then retreating.
Expect this trend to continue into early this evening, then
offshore flow should keep things clear for tonight. The marine
stratus just south of Crescent City towards Capetown is showing
signs of eroding and it's possible it could clear out towards
evening. Models are in fairly good agreement with the overall
picture for the week ahead. Conditions will remain dry through the
forecast period with warm temperatures for inland locations.
Offshore flow is expected to increase tonight bringing gusty
breezes over the higher terrain in del norte Humboldt and Trinity
counties along with moderate to poor humidity recoveries. The
thermal trough is expected to expand northward during the day
Thursday. This will weaken the offshore flow and we'll see the
marine stratus start to surge northward towards Point Arena and
Fort Bragg late Thursday afternoon or evening. The marine stratus
will continue to push northward through Capetown Thursday night
and will get close to Eureka. For now it looks like it will
remain offshore, but it will be close.

The thermal trough will continue to build north up through the Pacific
northwest Friday unto next weekend. We'll remain dry over the forecast
area with marine stratus along the coast and adjacent River Valley
locations with temperatures near or slightly below normal. Inland
skies remain clear with above normal temperatures. -Petrucelli


Aviation...low stratus continues to hug the coastline south of
Crescent City early this afternoon. Kacv should see ceilings burn off
within the next few hours...yet low clouds will remain along the
coast. VFR conditions are expected inland and across the kcec
terminal for the remainder of the afternoon. Stratus will likely
return after 06z Wednesday across coastal locations and persist
through the morning hours with VFR conditions and light winds at
kuki through the forecast period.


Marine...the gradient between high pressure offshore the Pacific northwest
coast and a thermal trough over the California Mainland will tighten over the
next 24 hours. This is increasing north winds to solid gale force over
the waters beyond 10 nm. The gales over the outer waters will bring
steep seas to the waters nearer to shore north of Cape Mendocino.
The hazardous seas watch has been upgraded to a warning for those
waters. The pressure gradient will relax fairly rapidly Wednesday night as
the thermal trough shifts toward the coast. Jbl


Fire weather...the short wave digging into the pacnw through
tonight will produce drier air and an increasing offshore pressure
gradient over the district tonight into Wednesday. The result will
be poor overnight recoveries and continued very dry afternoon
minimum humidity Wednesday. Have gone with a red flag warning for
this occurrence which will match up well with the headline from the
Medford weather forecast office. Coordination with area imets resulted in not issuing a
watch for the continued condition expected through Thursday morning.
But we do expect the dry and breezy condition to likely continue
across the ridges in at least zones 203 and 204. So stay tuned.
The thermal trough will spread north and the gradient slackens
Friday so the winds will weaken. Low pressure that develops off
northern California Friday and moves slowly across the area over
the weekend looks like it'll leave the area free from
lightning...which was a concern at one point for some. Looks
fairly dry and none of the models are indicating any precipitation so
confidence is good. Stavish


Eka watches/warnings/advisories... flag warning from 11 PM this evening to 11 PM PDT Wednesday

Northwest California coastal waters...Small Craft Advisory until 9 am PDT Thursday pzz450.

Hazardous seas warning from 3 PM Wednesday to 3 am PDT Thursday

Small Craft Advisory from 5 PM this afternoon to 3 am PDT
Thursday pzz455.

Gale Warning until 8 am PDT Thursday pzz470.

Small Craft Advisory until 5 PM PDT this afternoon pzz475.

Gale Warning from 5 PM this afternoon to 2 am PDT Thursday



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