Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA

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799
FXUS66 KHNX 112144
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
244 PM PDT Sat Oct 11 2025


&&

.KEY MESSAGES...

1. A strong trough is expected to bring a signification amount
of precipitation to the region Tuesday and Wednesday, with
moderate rainfall expected below 6500 feet and moderate to heavy
snow fall for elevations above 6500 feet.

2. There is a Marginal Risk (at least 5%) for excessive rainfall
on Tuesday for much of the Valley and Foothills north of Kern
County and along the Coastal Range.

3. There is an 80 to 90 percent chance for a half of an inch of
rainfall in 24 hours for Valley locations north of Visalia on
Tuesday, and similar chances for an inch of rainfall over a 48
hour period in the Foothills.

4. Snow levels with this system are expected to drop to around
6500 to 7500 feet by Tuesday, with snow totals of 4 to 8 inches
from 7000 to 8000 feet, and up to 1 to 2 feet in the higher
elevations of the Sierra Nevada. A Winter Storm Watch has been
issued for this period.

5. Long term forecasts are are mostly showing tranquil weather
the week after next, though some model members are showing the
possibility for further unsettled weather the Monday after next.
The ridging pattern may also mean the first fog event of the
season after this precipitation event.

&&

.DISCUSSION...
The big story is the next trough which slides down the
California coast Monday as it brings even more cooler
temperatures which will lower the snow level. In addition, the
setup will allow for Integrated Water Vapor Transport values of
at least 150 kg/(m*s) to be advected into the area as models
show a 80 to 95 percent chance of values that high moving in.
Latest probabilities have a 70 to 95 percent chance of at least
a foot or more of snow above 6,500 feet between Monday morning
and Thursday morning. A Winter Storm Watch is in effect from 11
AM Monday through 5 PM Wednesday.

However, we have a 25 to 65 percent chance of at least an inch
of rain in the Valley in 24 hours ending at 5 pm Tuesday. This
has led the WPC to put much of the Valley, the Sierra foothills,
and West Side Hills under a Marginal (5 to 15 percent) Risk of
Excessive Rainfall for Tuesday. The biggest concern with this
heavy rain is any debris flows from heavier amounts of rain over
the burn scars.

The long term ensemble models are mostly showing a tranquil
pattern setting up after this system moves out of the area, with
ridging setting up over the Southwest. However, there are some
members with another trough coming through to bring more
unsettled weather to the region. There is also a possibility
that the first fog event of the season may occur if the ridging
pattern verifies along with the large amount of rainfall coming
in with this upcoming system.

&&


.AVIATION...
VFR conditions are expected to prevail through the forecast period.

&&

.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 until 5 AM PDT Sunday for CAZ337>339.
Winter Storm Watch from Monday morning through Wednesday
afternoon for CAZ323-326>331.
&&

$$

EW

weather.gov/hanford