London, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

139
FXUS66 KHNX 120437
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
937 PM PDT Fri Jul 11 2025

.UPDATE...
Updated Aviation Section.

&&

.KEY MESSAGES...
1. A Heat Advisory has been issued for the San Joaquin Valley
an Sierra Nevada Foothills through early next week. 20 to 60
percent chance for greater than 105 degrees in the Valley today
and Saturday; 30 to 70 percent chance for Foothill areas to
exceed 100 degrees.

2. Low RH values 15 to 25 percent will stretch across much of
the San Joaquin Valley and Sierra Nevada with values 5 to 10
percent in the Mojave Desert. RH will decrease over the region
later in the week with warming temperatures.

3. 50 to 100 percent chance or temperatures to exceed 105
degrees for much of the Kern Desert over the weekend; 50 to 70
percent chance for Inyokern and Ridgecrest to exceed 110 on
Monday.

&&

.DISCUSSION...
High pressure has come to a rest over southern California today,
leading to an increase in temperatures compared to earlier this
week. Widespread triple digit afternoon highs are expected today
through the weekend as a result of this synoptic pattern, with
a 20 to 60 percent chance for greater than 105 degrees in the
San Joaquin Valley today and Saturday and a 30 to 70 percent
chance for 100 or more in the Sierra Foothills. For the Kern
Desert, there is a 50 to 100 percent chance to exceed 105 each
day through Monday. NE Kern County, including Inyokern and
Ridgecrest have a 50 to 70 percent chance to exceed 110 on
Monday. Due to these warmer temepratures, a Heat Advisory has
been issued for the San Joaquin Valley and areas of the Sierra
Foothills valid from 11 AM this morning through 11 PM Tuesday.

The warming temperatures across the region will cause relative
humidity values to decrease, with widespread values between 15
and 20 percent for the valley and mountain areas today, and a
slight improvement to 15 to 25 percent Saturday through Monday.
Desert RH values will continue to remain largely below 10
percent through the forecast period.

A slight cooldown is anticipated in the middle of next week as
the aforementioned ridge breaks down. However, temperatures
will still be near normal for this time of year. MinRH will
improve with the cooler temperatures, with widespread values 25
to 30 percent anticipated for the valley areas.

The dry conditions across the region will prolong dry
conditions favorable for fire development, however with
subsiding air aloft associated with the area of high pressure,
winds will generally be light. The strongest winds will be in
typical wind- prone areas such as the Mojave Desert Slopes, Lake
Isabella, and Pacheco Pass, with the diurnal cycle being the
main driver.

&&


.AVIATION...
06Z Update:

VFR conditions will prevail for the next 24 hours across the Central
California Interior.

&&

.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...
Heat Advisory until 11 PM PDT Tuesday for CAZ300>322-324-325-
332.
&&

$$

public/aviation...McCoy/BSO

weather.gov/hanford