Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 262220 AAA
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
320 PM PDT MON SEP 26 2016
.UPDATE...Updated air quality issues.
Much above normal temperatures will begin a gradual cooling trend on
Tuesday. Highs will fall back to near normal by Friday then several
degrees below normal next weekend. A surge of tropical moisture will
bring a slight chance of showers and thunderstorms to the mountains
on Wednesday and Thursday.
.DISCUSSION...Ridge of high pressure bringing further warming today
with 24hr trends up several degrees in the San Joaquin Valley. Most
areas will top out in the upper 90s, but some locations will reach
the century mark, possibly for the last time this year. An offshore
surface flow continues to produce some gusty winds to around 30 mph
through passes in Kern county.
An upper low spinning over Baja CA today will drift north to over
SoCal by Wednesday. Mid level moisture is progged to spread in for
scattered clouds and the SREF continues to indicate the potential
for precipitation over the mountains and desert. Have bumped up
pops and increased coverage a little for a slight to low chance
over the southern Sierra and Tehachapi mountains, with a slight
chance into the Kern county desert. The best chance is on Wednesday
afternoon and evening, then a slight chance along the Sierra crest
on Thursday as the low weakens and shifts northeast.
A modest cooling trend will occur through Wednesday as the low
approaches, with highs remaining above normal. Medium range models
are in good agreement with a significant change in the pattern
later this week. An upper low off the British Columbia coast
Wednesday will drop south to the Pacific NW next weekend with a
long wave trough shifting over the west coast. Temperatures will
lower to near normal by Friday then fall to several degrees below
normal next weekend. High temps are forecast to be around 20 degrees
lower next weekend compared to today. Dry conditions are expected
with this system as moisture is limited this far south. But winds
will become breezy to gusty Friday afternoon through Saturday night.
VFR conditions will prevail over the Central CA interior during the
next 24 hours.
.AIR QUALITY ISSUES...
On Tuesday September 27 2016... Unhealthy for sensitive groups in
Fresno and Kings 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
www.weather.gov/hnx/certainty.php for additional information
an/or to provide feedback.