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Area forecast discussion 
National Weather Service Eureka California
345 PM PDT sun Aug 31 2014

Synopsis...high pressure building over the area will allow for a
clear night across much of northwest California. Patches of fog and low
clouds are possible along the coast as the marine layer
compresses. Labor Day will bring continued warming to the interior regions
while the coast remains seasonable.


Discussion...models remain in good agreement with a weak upper
ridge nosing into the region. Afternoon WV satellite is showing a
shortwave moving into the Pacific northwest which is keeping the clouds mixed
out today. As the ridge takes hold, the marine layer will be
compressed to the lowest levels along the coast. However, weak
offshore flow is expected overnight which should keep the air mass
dry and inhibit the widespread fog and low clouds along the coast.
With northwest flow over the waters and the Humboldt Bay region facing
WNW, have opted to keep some clouds and fog in the area due to the
ease of marine moisture to work its way into the area. Otherwise,
most areas should remain fair.

Overnight low across the interior should remain mild under offshore
flow, especially around the del norte region. This will help Labor
Day to start on the warm side which will easily put US ahead for maximum
temperatures. Look for a warm up of 2 to 7 degrees across the interior.
Labor Day at the coast is expected to be nice with mild temps,
plenty of sunshine, and afternoon onshore winds.

The ridge will begin to shift eastward on Tuesday allowing for a
slight cooling. Models continue to indicate an upper trough driving
in from the northwest during the second half of the week. While a cool down
is a sure bet, showers and thunderstorms are not. Models continue to
show the trough picking up the remnants of tropical system Marie,
but how much moisture remains with it and where exactly it will make
its way ashore remains very uncertain. So have left the medium to long
range forecast untouched. Bfg


Aviation...mostly clear skies will continue to prevail through
Monday. Offshore flow will suppress stratus development tonight. A
few patches of stratus and fog may form around Humboldt Bay and in
the Eel Delta/valley early Monday morning. These patches should
clear out fairly quickly with daytime heating. However the NE-east
wind flow will probably transport patchy smoke westward and
southward by early Monday morning. The smoke will create visibility


Marine...high pressure centered 1400 miles west of Eureka will
continue to slowly build eastward through early next week. This
ridge coupled with thermally induced low pressure over the
California interior will maintain moderately strong north winds
through middle week. Winds may reach gale force on Tuesday and Wednesday as
high pressure aloft strengthens and a low pressure system moves
into the northern rockies. Northerly gusts of 35-40 knots will be
possible in pzz470 on Tuesday and Wednesday as thermally induce low pressure
intensifies along the northern California coast. It is still a
couple days out and the models may be too high on the winds. For
now will hold off on hoisting a gale watch until the event becomes
more certain.


Fire weather...very dry conditions are expected to continue
tonight through Monday night as high pressure settles in and
offshore flow develops. Recoveries are expected to be poor
tonight, including along ridges, due to warmer overnight lows and
decreased dewpoints. Some of the offshore flow may become gusty
along the ridge in the morning hours. Monday will be a hot dry
day. See the general discussion for information on the synoptic
conditions. Tuesday will be a transition day followed by a cooling
and moistening trend for the second half of the week. Bfg


Eka watches/warnings/advisories...
Northwest California coastal waters...Small Craft Advisory from 3 am Monday to 10 PM PDT Thursday

Small Craft Advisory until 10 PM PDT Thursday pzz475.



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