Onyx, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

457
FXUS66 KHNX 190901
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
201 AM PDT Thu Sep 19 2024


.KEY MESSAGES...
1. There is a 40 to 60 percent probability for 0.10 inch or
more of rainfall in the San Joaquin Valley on Today and a 10 to
25 percent probability for 0.25 inch or more.

2. There is a 50 to 80 percent probability for 0.25 inch or
more of rainfall across the Sierra Nevada from Fresno County
north and less than a 50 percent probability south of Fresno
County. There is a 25 percent probability for 0.50 inch or more
rainfall in Yosemite Valley on Today.

3. There is a 49 percent probability for 1 inch or more of
snowfall at Tioga Pass on Today and a 24 percent probability
for 2 inches or more. Snow levels will be around 9,000 feet.

4. There is a 30 to 40 percent chance for thunderstorms across
the Sierra Nevada and West Side Hills on Today, highest around
Yosemite NP. There is a 15 to 20 percent chance for
thunderstorms across the San Joaquin Valley and West Side Hills
on Thursday.

5. Temperatures will be 10 to 15 degrees below normal through
Thursday before a weekend warmup. There is a 30 to 50 percent
chance of High temperatures reaching 100 degrees by Tuesday.

&&

.DISCUSSION...
Isolated showers continue across the Central California
Interior as the associated upper low moves further down the
coast this morning. Satellite and upper-air analysis show the
center of the disturbance just off the Central Coast and showing
a trajectory toward Santa Barbara. Being that the disturbance
will take a coastal hugger track, higher precipitation values
will remain west of the Coastal Range with up-slope
precipitation dominating Central California. This means
mountainous terrain will be favored for any significant
precipitation values. Therefore, the Valley, north of Fresno
County will have a difficult time receiving more than 0.01
inches of rain. The strong west to northwest wind flow aloft
will keep temperatures near their Wednesdays values as little
change is expected today. Evens as winds aloft reach speeds of
25 to 30 mph, cool air resides over the Kern Desert as indicated
in the relaxed surface pressure gradients. Currently, the KSFO
to KLAS gradients sits at around 4mb. Therefore, will not expect
strong surface winds today. Being on the right-side of the
upper low, instability will be favored across the district as
thunderstorm development will be possible this afternoon. Upper
low expected over Southern California by Friday with lingering
showers over Central California. Afterward, high pressure
returns as the region will see another round of warm
temperatures.

Ensembles have a good handle on the current situation of moving
another disturbance along the California Coast today. Based on
the trajectory of the disturbance hugging the coast during the
day, precipitation chance are better across the Sierra Nevada
than the San Joaquin Valley. This is noted in both Probability
of Measurable Precipitation (PoP) and Probability of Thunder
(PoT). Both show PoP of up to 80 percent for the Mountains and
near 60 percent for the Valley today. PoT is similar with 30 to
40 percent over the Sierra and 25 percent or less over the
Valley. With snow level near 9,000 feet, unsettled weather is
covered by a Winter Weather Advisory. Due to the elevation of
expected snowfall the snowfall probabilities for the favor area
of Tioga Pass are listed as follows:

Tioga Pass(Yosemite) 24 Hour snowfall  49% >1 inch
                                       24% >2 inches
                                        3% >4 inches

Friday will see lingering showers as moisture banks-up along
the south end and east side along the foothills. The ridge
pattern returns this weekend with drying and warming going into
early next week. Probability of Exceedance of reaching 100
degrees moves up to around 30-50 percent next Tuesday. While
summer will end on Sunday, 100 degrees still has one last chance
before September ends.

&&

.AVIATION...
Areas of MVFR and local IFR visibilities near wildfires.
Mountain obscuration over the Sierra Nevada after 18Z Today due
to rain and snow showers. Otherwise, VFR conditions will
prevail across the central CA interior over the next 24 hours.

&&

.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...
Flood Watch from 5 AM PDT early this morning through this
evening for CAZ308-313-336.

Winter Weather Advisory until 8 PM PDT this evening for CAZ323-
326-328-330.

&&

$$

Operations......Molina
Support/IDSS....JPK

weather.gov/hanford