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018
FXUS66 KHNX 130008
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
408 PM PST Thu Dec 12 2019


.SYNOPSIS...A few light showers are possible over Yosemite NP
tonight. Otherwise, high pressure will provide dry weather with
areas of dense fog across the San Joaquin Valley overnight and
into the morning. Another Pacific storm system will bring more wet
weather Friday afternoon through the weekend, mainly over the
mountains.

&&

.DISCUSSION...
Fog cleared early today allowing temperatures to warm well into
the 60s across much of the SJ valley. A few light showers will be
possible towards the high country of Yosemite this evening as a
moist westerly flow continues to bring mid and upper level
moisture across central CA. Lower level clouds has pushed into the
north sectors of the central valley due to an upper disturbance
within the west flow. Models show the lower level moisture moving
south across the valley. Thus fog forecast for the valley will be
tricky with the mix of low and high cloud cover. Think areas of
fog will be probable but with a mix of stratus and fog.

The ridge loses its grip a bit on Friday as an upper trough takes
aim on the Pacific Northwest. This shifts the storm track farther
south over central CA with precipitation arriving around Yosemite
by late morning. Models show the fetch of moisture and
precipitation spreading southward through the day and into Kern
County overnight into Saturday morning. QPF gives from 0.5" to 1"
liquid around Yosemite NP. Snow levels start out around 8000 feet
on Friday then lower to around 7000 feet late night and near 6000
feet by Saturday morning as the precipitation tapers off. A Winter
Weather Advisory remain in affect for the Central Sierra zone
above 7000` from Noon Friday until 10 AM Saturday. Total snow
accumulations of 4 to 8 inches with localized amounts up to 10
inches is forecast. QPF farther south is 0.25" to 0.5" for
Sequoia/Kings Canyon NP; and 0.1" to 0.2" down into the Kern
County Mountains. Rainfall across the SJ Valley is expected to be
very light with generally only a few hundredths to a tenth of an
inch. A few showers may linger through Saturday and into the
evening then as a second disturbance quickly follow the
aforementioned system. The secondary disturbance drives inland
over NorCal and the Great Basin Saturday night into Sunday
morning. This should bring a fairly quick shot at some more
precipitation but it will not have the rich subtropical moisture
plume to work with anymore. Though we do not expect significant
amounts with this system, but snow levels will be lower and could
be down around 4000 feet by Sunday morning. Gusty winds will
develop through the mountain passes in Kern County this weekend
and may reach advisory levels on late Saturday and Sunday.

Dry conditions are forecast Sunday night into early next week as
an upper ridge builds in from the Pacific. Models agree with an
upper low offshore of California next Tuesday but diverge from
there. The latest GFS moves it inland on Wednesday with healthy
QPF depicted over central CA; similar to the GFS Ensemble mean.
But the Euro and Canadian models keep it offshore until Thursday
and are much lighter with the precipitation. Thus have lower
confidence with the weather system for late next week.

&&

.AVIATION...In the San Joaquin Valley, areas of IFR/LIFR in fog
and low clouds 08z-18z Friday. In the Sierra Nevada areas of
mountain obscuration increasing through 00z Sat. Otherwise, VFR
conditions expected elsewhere across the central CA interior for
the next 24 hours.


&&


.AIR QUALITY ISSUES...
On Friday December 13 2019... Fireplace/Wood Stove Burning Status
is: No Burning Unless Registered in Fresno... Kern... Kings...
Madera and Merced Counties.
Further information is available at Valleyair.org



&&

.CERTAINTY...

The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
an/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from noon Friday to 10 AM PST Saturday
for CAZ192.

&&

$$

public...MV
aviation....MV

weather.gov/hanford