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Area Forecast Discussion (AFD)

Issued by San Joaquin Valley, CA (HNX)

FXUS66 KHNX 202236

Area Forecast Discussion
National Weather Service Hanford CA
336 PM PDT Fri Sep 20 2019

A warming trend is expected this weekend. Temperatures should 
drop back down to seasonal values Monday. Rain showers and high 
elevation snow showers are possible in the Southern Sierra Nevada 
Monday and Tuesday. Outside of the mountains, dry weather will 


A cool start start to the day this morning, just few cumulus 
clouds developing over parts of the Sierra Nevada. Otherwise a 
sunny and cool day across the central CA interior. Weak 
disturbances moving through the flow will maintain a north flow 
aloft tonight. This should continue to provide offshore flow with
clear and dry conditions. In addition surface high in the Great 
basin also providing offshore flow over the high desert and 
Tehachapi Mountains. An upper trough in the N Rockies will move NE
allowing a ridge in the EPac to build inland over the west coast. 
This will bring warmer temperatures across CA for the weekend. 
Models in better consensus with the next weather system affecting 
the district early next week. Models have trended further west 
with the system and move it southward across the entire state from
north to south. Flow turns onshore late Sunday as the upper 
trough pushes into N CA. 

The upper low closes over central CA as it progresses southward.
There may be enough atmospheric instability and moisture for rain
showers and high elevation snow showers Monday afternoon in the 
Southern Sierra Nevada. The low pushes into SCal Monday night and
stalls near the Mexico border Tuesday. The system may pick up some
remnant tropical moisture and as a result, precipitation chances 
will also shift southward. Ensemble means show precipitation 
towards the SE CA, thus a few showers cannot be ruled out in the 
Kern County mountains and desert Tuesday.

A strong upper low for this time of the year may begin to move 
southward near the west coast of Canada Thursday. This may allow 
temperatures to return to seasonal values Thursday. This system 
may bring a strong onshore flow with stronger winds and fall 
temperatures for next weekend across much of CA. 


VFR conditions will prevail at MCE, MER, FAT, VIS and BFL through
at least 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
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