Projected Precipitation for Mariposa and Oakhurst: 0.25" - 0.50"
Projected Precipitation for Yosemite Valley: 0.50" - 1.00"
September 28, 2023 - National Weather Service Hanford Office officials report a cold front will pass across Central California Saturday, resulting in a chance of rain and high elevation snow in the Sierra Nevada.
Snow levels will be around 8,000 feet.
The majority of this precipitation will fall during the day on Saturday.
Area Forecast Discussion
National Weather Service Hanford CA
230 AM PDT Thu Sep 28 2023
.SYNOPSIS...
Little change in the weather expected until Friday. By the end of
the week, a cool-down will bring cloudier skies and temperatures
around 10 degrees below normal. There will be an associated
chance for precipitation in the mountains and surrounding
foothills, including a chance for snowfall at the crest of the
Sierra Nevada. Conditions will return back near normal to start
next week.
&&
.DISCUSSION...
Sunshine and pleasant temperatures dominate the Central
California Interior on Wednesday. Thursday will see little change
as more sunshine is in store. The San Joaquin Valley saw
temperatures rise into the mid 80s on Wednesday. NBM probability
of exceeding 85 today is a bit lower but still above 30 percent.
Therefore, until a significant pattern change occurs, will expect
temperature to reach into the 80s. Ahead of the storm expected on
Saturday, Friday will be a transition period with winds being the
main weather parameter changing over the region. Will see a piece
of energy swing through Central California on Saturday as cooler
temperatures, continued winds and precipitation will enter the
area.
Pleasant conditions expected on Thursday and Friday. Saturday
will see a change to more unsettled conditions. Saturday will be
the big transition day as a piece of energy drops into the region
from the Gulf of Alaska. Ensemble upper-air Cluster Analysis has
very good agreement with dropping a deep trough over the West
Coast this weekend. Cluster Analysis shows minimal timing the
position error on Saturday. While some error does develop on
Sunday, enough agreement exist to indicate that a change to cooler
and unsettled conditions will exist over the region during the
weekend. NBM probability of exceedance of reaching 80 degrees
drops to near zero on Saturday. At best, NBM probability of
exceedance values do not reach 30 percent until the percentage is
set to 74 degrees. Therefore, the San Joaquin Valley is expecting
a 10-15 degree drop in temperatures from Friday to Saturday.
Ensembles do show a slight rise in temperatures toward the middle
of next week. Yet, the rise will be slow as it will be mid-week
when probability of exceedance of reaching 80 degrees reaches 60
percent next Tuesday.
Ensemble only offer a quick shot of precipitation associated with
the passage of the disturbance near Saturday. At that time,
ensembles (NBM) places the probability of exceedance of receiving
0.01 inches of precipitation between 20 and 30 percent. Due to the
time of year as we start a new water year, the percentages are
in-par with climo for this time of year. Therefore, its reasonable
to expect measurable precipitation this time of year. In
addition, NBM also places about a 20 percent chance of thunder on
Saturday. Instability, while weak, is being generated over Central
California on Saturday. Therefore, support is growing that
showers and thunderstorms will hit Central California this
weekend.
&&
.AVIATION...
MVFR conditions are likely to exist in areas around the Redwood
Fire in Sequoia National Park. Otherwise, VFR conditions will
prevail across the Central California interior throughout 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...
None.
Source: NWS
