Riverdale, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

587
FXUS66 KHNX 251119 AAA
AFDHNX

Area Forecast Discussion...UPDATED
National Weather Service Hanford CA
419 AM PDT Fri Apr 25 2025


.UPDATE...
Updated AVIATION section.

&&

.KEY MESSAGES...
1. Temperatures will see a cooling trend ahead of a disturbance
moving into the area this weekend.

2. Winter-like weather on Saturday as valley rain and mountain
snow will be observed.

3. A slight chance (20%-35%) of high Sierra Nevada afternoon
thunderstorms.

4. Locally breezy conditions expected across the Mojave Desert
this weekend.

&&

.DISCUSSION...
Cooling trend and breezy conditions have begun across the area
as Probability of Exceedance (PoE) of reaching 80 degrees drops
to 20% today and below 10% in the coming days. By Saturday, PoE
of reaching 70 degrees is below 10% across the San Joaquin
Valley. This drop increases confidence in a significant cool-
down by Saturday as temperatures fall some 10-15 degrees below
seasonal normal values. Confidence is the upper-air ensemble
analysis is growing as we lean toward the introduction of a cold
trough pattern this weekend.

Ensemble analysis is now leaning toward widespread
precipitation becoming likely across most of the San Joaquin
Valley. Mountain locations will have a better chance of
measurable amounts. Current PoE of measurable precipitation sits
at 30%-40% from Merced County toward Yosemite NP on Friday
night and 30%-50% on Saturday with near 50% for the higher
elevations near Yosemite. Therefore, while confidence on
mountain precipitation is growing, valley rain still has high
uncertainty south of Fresno County. Thunderstorms will be a
threat this weekend over area as probabilities trend higher over
the last few days. This threat includes the San Joaquin Valley,
foothills and Sierra Nevada. In addition, more snow will
accompany the rain and thunderstorms as Saturday will look very
unsettled. Storm moves out around Sunday with ridging, drying
and warming dominating the period from Monday through at least
next Thursday.

As for the winds, ensemble surface wind analysis shows an
increase in gusts over the Mojave Desert as speeds reaching into
the upper 30 mph range. Saturday looks more promising with PoE
of 55 mph winds sitting between 40%-55%. Will issue an advisory
as the event nears. Then, a return to ridge will decrease winds
for the remainder of the period.

With the storm`s exit later in the weekend, temperature begin a
rebound and rise to the mid 80s by Tuesday. The PoE of mid 80s
jumps up to a range of 40%-60% at that time. As a note, PoE of
90 degrees sits at 30%-40% by next Wednesday. Thursday shows
slightly high probabilities and implies continue warming into
the latter part of next week.

&&

.AVIATION...12Z:
VFR conditions will prevail across the central CA interior
through the next 24 hours.

For the Mojave Desert and Slopes, strong winds 25 to 35 mph and
gusts up to 50 mph expected. A Wind Advisory remains in effect
for this area through 18Z Sunday.

&&

.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...
Wind Advisory from 5 PM this afternoon to 11 AM PDT Sunday for
CAZ337>339.
Winter Weather Advisory from 11 PM this evening to 11 AM PDT
Sunday for CAZ323-325>330.

&&

$$

Public/Aviation....Molina

weather.gov/hanford