Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA

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FXUS66 KHNX 152216

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
216 PM PST Mon Jan 15 2018

.SYNOPSIS...A cold front will move southward across the area
tonight and early Tuesday bringing a chance of light precipitation
mainly from Fresno county northward. A colder storm will bring
rain and mountain snow to the region Thursday through Friday.


.DISCUSSION...Another morning of dense fog took place over much of
the San Joaquin Valley as the low cloud deck broke up Sunday
afternoon in response to a mid level shortwave which pushed
across central CA on Sunday. This allowed for clearing to take
place earlier this morning, and with light winds prevailing and a
low level inversion persisting; widespread dense fog formed over
the San Joaquin Valley prompting the issuance of a Dense Fog
Advisory earlier today which was later extended until noon then
allowed to expire as visibility finally improved. However, some
low clouds persist over portions of the valley this afternoon

The upper ridge that was responsible for the mild and dry weather
over the mountains and deserts as well as the daily persistent
fog and low clouds over the San Joaquin Valley will break down by
the evening as an upper shortwave takes aim at Norcal. WRF has
been trending further north with this system with each run and it
is now expected to just brush areas from Fresno County northward
with some light precipitation tonight and early Tuesday with
rainfall amounts expected to range from a trace to a few
hundredths in these areas. Up to an inch of new snow is possible
above 7000 feet in the southern Sierra Nevada.

Shortwave ridging will build into central CA behind this system
on Tuesday Night and Wednesday which will result in another period
of dry weather for our area. Once again, fog will be possible in
the San Joaquin Valley Tuesday night and Wednesday mornings as
clearing skies, light winds and inversion conditions over the
valley will support fog development.

The WRF is in good agreement with the medium range models in
bringing a colder and wetter system into our area by late
Thursday. This system is expected to push southward across our
area on Thursday Night and produce significant precipitation.
Colder air will push into our area behind this system on Friday
resulting a cool, showery and blustery day across our area. Snow
levels will be between 7000 and 8000 feet at the onset of
precipitation on Thursday, but lower to 3000 to 4000 feet by the
time the precipitation tapers off Friday Night. While the models
have been trending toward somewhat less precipitation with this
system, it will still produce significant snowfall in the
mountains and has the potential to disrupt travel over the
commonly traveled roads over the lower elevations of the Southern
Sierra Nevada as well as the passes in Kern County on Friday. Rain
shadowing will likely keep precipitation totals down in the San
Joaquin Valley although wetting rains are still anticipated.

The medium range models are in fairly good agreement with a
shortwave ridge over our area on Saturday and Satruday Night which
will bring a dry period to our area, and then bring another
system into Central CA by late Sunday which might provide for
another round of precipitation for our area Sunday Night and next


.AVIATION...Areas of MVFR conditions in clouds and mist/haze will
persist in the San Joaquin Valley with lingering local IFR
through 06Z Tuesday. A storm will push into the area after 06Z
Tuesday, with widespread MVFR conditions and local IFR in
precipitation, mainly Fresno County northward. Otherwise, VFR
conditions will prevail across the Central CA Interior during the
next 24 hours.


.AIR QUALITY ISSUES...On Tuesday January 16 2018...
Fireplace/Wood Stove Burning Status is: No Burning Unless
Registered in Fresno... Kern... Kings and Tulare Counties. Further
information is available at



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 for additional information
an/or to provide feedback.


.HNX Watches/Warnings/Advisories...NONE.



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