San Joaquin, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

398
FXUS66 KHNX 230529
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
Issued by National Weather Service San Diego CA
350 PM PDT Sun Jun 22 2025

.UPDATE...Updated Aviation section.

&&


.KEY MESSAGES...
1. Major cool down Today with humidities slowly recovering.
Better recovery occurring across the Sierra Nevada.

2. A weak disturbance crossing the region on Monday will allow
for afternoon convection across the Sierra Nevada from Yosemite
down to Fresno County.

3. Warming trend starting on Monday as temperatures return to
triple-digit values across the San Joaquin Valley later in the
week.

&&

.DISCUSSION...
A significant disturbance that produced strong winds and
elevated fire weather concerns exits the region as a weaker
disturbance is now poised to cross. While the disturbance will
have little effect on the winds and temperatures over the
region, it will be enough to generate afternoon showers and
thunderstorms over the Sierra Nevada Crest from Yosemite to
Fresno County on Monday. By Tuesday, zonal flow and weak ridging
will allow for a slow warm-up with ever better chances of
reaching 100 degrees late in the week.

To start, Ensemble Probability of Thunder (PoT) will grow to
nearly 20% on Monday across the Sierra Nevada during the weak
disturbances passage. Elsewhere, PoT will remain at near zero
values during the week. The Sierra Nevada Crest will also drop
to very low percentages as the disturbance exits the region on
Tuesday and Wednesday. Afterward, the region will be dominated
by a developing ridge pattern as dry conditions prevail.

Temperatures will start a slowing warming trend and begin
reaching toward triple digit values later this week. The first
hint toward 100 degree temperatures will be seen on Wednesday as
isolated favored locations register with 10%-30% Probability of
Exceedance (PoE) of reaching 100 degrees. By Thursday, the PoE
grows to near 50% which increases confidence is reaching triple-
digit values. While long range ensemble solutions do not hint
towards any strong heat-waves, the potential of near triple-
digit temperatures exist to keep Central California on the warm
side for much of the week.

&&


.AVIATION...
06Z Update:

VFR conditions will prevail for the next 24 hours across the
Central California Interior. A few clouds building over the
Sierra Nevada Crest during the morning hours after 16Z Monday.

&&

.AIR QUALITY ISSUES...
None.


&&

.CERTAINTY...

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
www.weather.gov/hnx/certainty.html for additional information
and/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

CMolina/BSO

weather.gov/hanford