Atwater, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

538
FXUS66 KHNX 211130
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
330 AM PST Thu Nov 21 2024


.KEY MESSAGES...
1. Temperatures will warm to around 5 to 10 degrees above
climatological averages on Thursday and Friday.

2. A strong winter storm system is forecast to impact Central
California Friday night through this weekend. Portions of the
San Joaquin Valley and the Sierra Nevada Foothills may see
moderate to heavy rainfall rates at times with moderate to
heavy snowfall rates in the Sierra Nevada.

3. The probability of receiving between one-half and one
(0.5-1.0) inch of rain by 4 PM Saturday is 90% in Merced
decreasing towards the south to 80% in Fresno, 50% in Visalia,
and 20% in Bakersfield.

4. The snow level will lower to near 7,000 feet around Yosemite
NP at the onset of precipitation Friday afternoon. The
probability of receiving 12 inches of snow by 4 PM Saturday is
85% for Tuolumne Meadows and 90% for Tioga Pass.

&&

.DISCUSSION...
A strong cyclone continues to sit out over the Northeastern
Pacific with plenty of energy traveling onshore and into the
Pacific Northwest. This energy has resulted in significant
precipitation north of the district as some locations in
Northern California have received over 3 to 4 inches in the past
24 hours. So far, the district remains dry as the moisture and
dynamic lift target areas to our north. In addition to the
precipitation, strong winds have also developed to our north as
speeds have reached 40 to 50 mph. This far south of the jet max,
winds remain in the 5 to 15 mph range. These conditions are
expected to change once a piece of energy drops closer to
Central California and taps into the plume of subtropical
moisture (atmospheric river). Therefore, precipitation and
strong winds are expected as early as Friday afternoon with snow
falling at elevations above 7,000 feet.

High-Res short-range Ensemble Mean upper-air analysis keeps the
disturbance just north of the Central California Interior for
the next 24 to 36 hours. Therefore, confidence is high of the
dry forecast for today and Friday before the onset of
precipitation. While the onset of precipitation could start as
early as Noon on Friday, Probability of Measurable Precipitation
(PoP) doesnt reach 50 percent near Yosemite until closer to 4
PM PST. Afterward, more significant pieces of energy swing
through the area as the moisture plume spreads into Central
California. By 4 AM PST on Saturday, PoP reaches near 100
percent as ensemble place the area well within the Weak
Atmospheric River(AR) category and skirts the moderate AR
category. At these categories, ensemble precipitation analysis
has a probability of exceedance (PoE) of reaching 1 inch in 24
hours of 30-50 percent with spots hitting 60 percent. The target
area for heavy precipitation sits in the foothills from
Mariposa to Fresno County. An Excessive Rain Outlook has been
posted for these areas as flooding potential is possible with
the expected rain rate. The precipitation will also warrant a
Winter Storm Watch for the Sierra Nevada above 7,000 feet as 10
to 14 inches is expected by Saturday afternoon.

With little change in the weather pattern for the remainder of
the weekend and into early next week, precipitation will
continue to fall through at least Tuesday. Ensemble upper-air
analysis does not remove the upper level disturbance through the
area until Wednesday. Therefore, with several days of moisture
being pumped into the area, will maintain the Winter Storm Watch
through Tuesday. There is a bit of uncertainty on the passage of
the disturbance, yet, a high number of ensemble members do hint
toward having the disturbance exit by Wednesday. The end of the
week (day 7) hints toward a ridge developing. Yet, a percentage
of the ensemble members still hold on to a possible disturbance
over the West Coast. Will lean toward the drier pattern as fog
becomes the problem of the area as we reach next
Thursday/Friday.

&&

.AVIATION...
VFR conditions will prevail through the period at all terminals
as Probability of IFR conditions stands at 2-5 percent during
the next 24 hours.

&&

.AIR QUALITY ISSUES...
On Thursday November 21 2024, Fireplace/Wood Stove Burning
Status is: No Burning Unless Registered in Fresno, Kern, Kings,
Madera, and Tulare Counties. Burning Discouraged in Merced
County, and Kern (Greater Frazier Park Area) and Sequoia
National Park and Forest.

&&

.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...
Winter Storm Watch from Friday afternoon through Tuesday
afternoon for CAZ323-326>331.

&&

$$

Public/Aviation....Molina

weather.gov/hanford