Onyx, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

131
FXUS66 KHNX 121835
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
1135 AM PDT Sat Jul 12 2025


.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 103 degrees in the Valley today
and Sunday; 40 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 this weekend and early next week.
RH will increase over the region later in the week with cooling
temperatures.

3. 60 to 100 percent chance or temperatures to exceed 105
degrees for much of the Kern Desert over the weekend; 50 to 80
percent chance for Inyokern and Ridgecrest to exceed 110 on
Sunday and Monday.

&&

.DISCUSSION...
Lots of sunshine today as a ridge of high pressure sits over
the West Coast. The position of the high pressure center, just
off the California Coast, will lead to triple digit highs and a
lack of cloud cover over Central California. Heat Advisory
remains in effect across the Central California Interior as
afternoon highs will continue to reach into the range of 103-106
degrees. Overnight lows do offer some relief as temperatures
bottom out in the mid 60s. Based on the minimal movement of the
high pressure ridge, will see several more days of triple digit
heat before a potential cool-down around mid-week of next week.
The cool-down will be associated with a disturbance riding over
the Pacific Northwest on Tuesday and Wednesday. While no
precipitation will be associated with the disturbance, winds
will see an uptick on Tuesday over the wind prone areas of
Central California.

Confidence remains high in the current heat-wave as ensemble
Probability of Exceedance (PoE) of reaching 103 degrees across
the San Joaquin Valley remains in the 50%-80% range through
Monday. While Tuesday still shows a range of 50%-80% PoE, that
percentage will be for temperatures reaching 100 degrees.
Therefore, will maintain the Heat Advisory through Tuesday with
high confidence that Wednesday will transition toward below
triple digit heat. By mid-week, PoE of reaching 100 degrees
falls below 30%, which translates into high in the 90s for the
remainder of the period.

With the Tuesday to Wednesday time frame as a transitional
period from triple digits to 90s, winds will be on the increase.
PoE of reaching wind speeds of 40 mph will favor the wind-prone
areas of Kern County. Current PoE of 40 mph winds are in the
range of 50%-70% over the Mojave Slopes with a few spots
reaching PoE of 90%. Will monitor the situation for any possible
messaging on this Day 4 to Day 5 event. Otherwise, summer is
here as conditions stay from above to near seasonal normal for
the period.

&&

.AVIATION...
18Z 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/IDSS....Molina/SM

weather.gov/hanford