Area Forecast Discussion
Issued by NWS Sacramento, CA

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FXUS66 KSTO 231212
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
412 AM PST Sun Nov 23 2014

.Synopsis...
High pressure over the Eastern Pacific Ocean will begin to strengthen
today and then move into the West Coast Monday and Tuesday. Mild
weather expected for much of the week with above normal temperatures.

&&

.Discussion...
Overnight, there was a large area of dense fog in the Central &
Southern Sacramento Valley into the San Joaquin Valley from about
10 pm last night until 3 am this morning. In the past hour, the
fog has quickly lifted and scattered out across much of our region
as north winds begin to develop and high clouds move over the
area. Thus, have canceled the Dense Fog Advisory.

High pressure is developing over the Eastern Pacific Ocean and
will strengthen today into Wednesday as the ridge axis moves inland
over California. Expect fairly clear skies and mild weather as the
ridge dominates our weather pattern in the short term. Daytime
highs and overnight lows will be slightly to several degrees above
normal as we enter a warming trend. Valley highs will peak in the
low 60s today and then reach the upper 60s by Wednesday. Mountain
highs will go from the mid 40s to mid 50s today and warm about 10
degrees by Wednesday. North to easterly winds will develop today
with speeds generally on the light side. However, the western side
of the valley could get a little breezy this afternoon with gusts
ranging 10-20 mph.

The tricky part of the forecast will be early morning fog
development. We have kept patchy fog mentioned for the next
several mornings in the central valley and including mountain
valleys as overnight winds will be light. The ridge axis will be
very near or directly over our forecast area by Tuesday
morning. This increased subsidence aloft may help dense fog
development for portions of the valley as it traps moisture near
the surface and doesn`t allow it to mix out easily. Motorists
driving between midnight and sunrise should be aware that they
could encounter lowered visibilities while driving and be prepared
to slow down.  JBB


.Extended Discussion (Thursday through Sunday)

Upper ridge forecast to flatten over NorCal late in the week as
flow begins to break under the Gulf of Alaska blocking high. Still
some uncertainties on the timing of the onset of precip as the
initial system for later Friday into Saturday is forecast to be
rather weak as it moves into the mean ridge position. Another
weak system is forecast for Sunday with warm advection expected to
keep snow levels moderately high.

&&

.Aviation...

Northerly winds developing through the Central Valley as high
pressure rebuilds. General VFR conditions expected the next 24
hours with SCT-BKN cirrus clouds, except for lingering areas of
MVFR and local IFR conditions in stratus and fog S of KSMF through
about 14Z. MVFR conditions redevelop in the Central Valley after
03Z Mon.

&&

.STO Watches/Warnings/Advisories...
None.
&&

$$







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