FXUS66 KHNX 221903
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
1203 PM PDT Sat Aug 22 2026


.KEY MESSAGES...
1. Triple digit heat continues for San Joaquin Valley and Mojave
Desert.

2. Monsoonal moisture brings 10 to 20 percent chance of 
thunderstorms over the Sierra Nevada this afternoon.

3. 20-40% probability for extreme heat ending next week and
starting September.

&&

.DISCUSSION...
Upper level disturbance expected to swing around the ridge 
pattern today and cross into the Upper Inter-Mountain West on 
Sunday. While slight changes in temperatures and winds will be 
observed Today, the location of the upper level disturbance will
be too far north to generate significant drops in the 
temperatures or strong winds. Therefore, with Probability of 
Exceedance (PoE) of reaching 100 degrees average at around 60 to
80 percent from Fresno To Bakersfield, respectively, will see 
minimal change as max temperatures sit around around 100 degrees
each day. Areas north of Fresno will have PoE between 10 and 30
percent as upper 90s will be more representative of the region.
This situation will result in mostly Minor Heat Risk with 
patches of Moderate Heat Risk for most of the next seven days. 
Afterward, the disturbance will exit the region with a rebound 
of the ridge ahead of another disturbance traveling through the 
Pacific Northwest. These transitory disturbance will prevent any
big warm-up for the next five to seven days as the ridge 
pattern will not be allowed to amplify. Furthermore, PoE of 105 
degrees remains at near zero outside of the west side of Kings 
County and the Kern County portion of the San Joaquin Valley.

The passage of the disturbance will also introduce an increase 
in the southwesterly to westerly wind component during the 
coming days. Currently, the flow is more southerly and is 
allowing for a northward surge of Monsoonal Moisture into the 
region. With the southwest winds aloft Today, enough orographic 
lift will exist to support thunderstorm development across the 
Sierra Nevada Crest. Latest ensemble probability of thunder is 
between a 10 and 20 percent chance of development this Afternoon
from Yosemite to the Tulare and Kern County Line. By Sunday, 
the flow aloft becomes more westerly and forces the moisture to 
shift east and more into the Great Basin. Therefore, while 
convection is possible on Sunday, Central California will lose 
the ingredients for significant thunderstorm development as the 
probability of thunder drops to 5 to 10 percent. Probabilities 
continue to drop during the week as dry conditions prevail from 
Monday through at least Friday. 

&&

.AVIATION...
VFR conditions prevailing for the next 24 hours. 10-20% 
probability of afternoon thunderstorms from 18Z Saturday to 3Z 
Sunday along the Sierra Nevada crest down to 6,000 feet 
elevation.

&&

.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.

&&

$$

Public/Aviation....Molina

weather.gov/hanford