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FXUS66 KHNX 240018

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
418 PM PST Fri Feb 23 2018

Freezing temperatures will occur across much of the San Joaquin
Valle tonight with rural areas falling into the upper 20s and 
possibly near 25 degrees in a few locations. Dry weather and a
warming trend will occur this weekend then another cold storm
system arrives Monday for more precipitation and increased winds 
into Tuesday.


Upper trough is exiting to the east over the four corners region
with a cold northerly flow aloft across central California. Some
fairly good snowfall amounts occurred last night over the Sierra 
Nevada and even into the adjacent foothills. Generally, reports
were from 2-6 inches, but a few high Sierra locations received up
to 10-12 inches. Some light upslope showers have been developing 
through the day, mainly along the Tulare County foothills. These 
showers will end with sunset and clouds will mostly dissipate. An 
upper jet as well as an onshore surface pressure gradient has been
producing gusty winds across the San Joaquin Valley, generally in
the 20-30 mph. Gusts in the Kern County Mountains and Desert have
been in the 30-40 mph range. These gusts will rapidly diminish 
after sunset with light winds prevailing overnight.

A very cold air mass is in place, and with the clearing skies and
light winds overnight, a Freeze Warning is in effect for the San
Joaquin Valley tonight into early Saturday morning. Many rural 
areas will fall into the upper 20s by morning and a few locations
could bottom out near 25 degrees for an hour or two.

Dry weather will prevail this weekend though a disturbance moving
over the Great Basin Saturday evening could bring a few isolated 
light showers to the high Sierra from Yosemite NP to Kings Canyon 
NP. Little if any rain/snow accumulation is expected regardless.

Another cold storm system is expected to drop down from the north
on Monday into Tuesday bringing more precipitation and gusty winds.
The models want to track this next system a little farther west 
down the coast than the last one. This could provide better rain
amounts for the SJ Valley and current QPF generally has around a 
tenth of an inch. The mountains are looking at a quarter to half 
an inch QPF. Snow levels will again fall into the foothills, down
near 2500 feet. Gusty winds will develop as well and could reach
advisory level in some areas, most likely the Kern Co mtns/desert.

Medium range models are struggling a bit with another potential
storm system later next week. While not as impressive as it once
was depicted, it could still be a more significant precipitation 
producer, including for the SJ Valley. Current timing focuses on
Thursday and Friday of next week.


Mountain obscurations over the Southern Sierra Nevada and Kern 
County Mountains in low clouds thru Fri evening and over the high 
Sierra Saturday afternoon. Otherwise VFR conditions expected across 
the remainder of the Central CA Interior during the next 24 hours.





The level of certainty for days 1 and 2 is high.
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...
Freeze Warning from 2 AM to 8 AM PST Saturday CAZ089>092.




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