Includes Eastern Mariposa, Madera and Fresno Counties and Yosemite National Park
September 20, 2023 - National Weather Service Hanford Office reports a few strong thunderstorms are possible in the Sierra Nevada and adjacent foothills from 2:00 P.M. this afternoon until 7:00 P.M. this evening.
Dangerous cloud to ground lightning strikes, small hail, and localized flooding are hazards associated with strong thunderstorms.
Area Forecast Discussion
National Weather Service Hanford CA
1218 AM PDT Wed Sep 20 2023
.SYNOPSIS...
A few strong thunderstorms are possible in the Sierra Nevada each
afternoon and evening today and Thursday. Robust, southwest wind
gusts are expected in the Kern County desert Thursday afternoon
and Thursday evening. A few showers are possible in and around
Yosemite National Park early next week. Temperatures will remain
below seasonal values through at least the next seven days.
&&
.DISCUSSION...
An upper-level area of low pressure will move eastward across
Southern California today. This disturbance may provide enough
atmospheric instability for a few strong thunderstorms in the
Sierra Nevada and adjacent foothills this afternoon into this
evening. A cold front will move southward across Central
California Thursday. A few strong thunderstorms are possible ahead
of this cold front along the Sierra Nevada crest north of Tulare
County Thursday afternoon into Thursday evening. Robust, southwest
wind gusts are anticipated in the Kern County desert Thursday
afternoon and Thursday evening ahead of this cold front. A Wind
Advisory is in effect. High temperatures in the San Joaquin Valley
Thursday afternoon will be around ten degrees below normal for
this time of year. Here are probabilities of maximum temperatures
of 82 degrees or lower for select locations in the San Joaquin
Valley on Thursday, September 21st, 2023:
Porterville - 64%
Delano - 64%
Reedley - 64%
Fresno - 54%
Visalia - 54%
Hanford - 54%
A low amplitude ridge of high pressure will progress eastward over
the Western United States Friday. This ridge of high pressure will
strengthen over the Central United States this weekend. A trough
of low pressure may approach the service area early next week.
&&
.AVIATION...
MVFR or lower conditions are likely in and near isolated showers
and thunderstorms in the Sierra Nevada from 21Z this afternoon
until 02Z this evening. Otherwise, VFR conditions will prevail
across the remainder of Central California.
&&
.AIR QUALITY ISSUES...
None.
&&
.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
and/or to provide feedback.
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 2 PM to 11 PM PDT Thursday for CAZ337>339.
Source: NWS
