textproduct: San Joaquin Valley

KEY MESSAGES

1. A Flood Watch is in effect for the Sierra Nevada below 9,000 feet and foothills, mainly Yosemite, as well as Mariposa and Madera Counties until Friday. The Flood Watch will then cover all portions of our forecast area mainly up to 7,000 feet from Tuesday afternoon until Friday afternoon.

2. Chances for precipitation, with moderate to heavy amounts at times, continue for the Sierra Nevada and its foothills from Fresno County northwards through Tuesday morning.

3. A second, stronger system is expected to arrive by Tuesday afternoon, with a moderate risk for heavy precipitation throughout Central California, and a moderate risk for heavy snow in the Sierra Nevada expected from Christmas Eve through Friday of next week.

4. Gusty winds will also impact much of the forecast area from Tuesday afternoon until Christmas Day with downed trees and large branches possible.

DISCUSSION

A very active period with impactful precipitation and gusty winds begins late Tuesday afternoon and lasts through Christmas Day. Some increase in winds will be noticed in the Central Valley, with downed trees possible with the strongest winds, such as towards the west side, the south end near Bakersfield, and Merced County. Gusty winds will also impact the typical prone areas including the coastal ranges and the Kern County mountains and desert. Until tomorrow afternoon, we can expect mostly cloudy skies with mild temperatures.

There is some risk of heavy precipitation towards the Kern County mountains, as the Weather Prediction Center shows at a slight (15-40% chance) risk for this area, including along Interstate 5 through the Grapevine. Currently, the probability for at least 3 inches of rain to fall in this area is around 50-60 percent and a 10-20 percent chance for 6 inches or more. There are even higher chances (65-75%) over northern portions of our Sierra Nevada, mainly below 7,000 feet to receive a total of at least 6 inches. The chances for one inch of rain per 24 hours during Tuesday afternoon until Christmas Day in the Central Valley are as high as 60-70 percent, with lesser chances towards the middle portions and anywhere where rain shadowing occurs. We will keep the Flood Watch in effect for much of our forecast area, as the likelihood for widespread moderate to heavy precipitation has been consistently high for quite some time. Expect rises along waterways and minor flooding to occur due to this precipitation. Recent burn scars, especially those due to the Basin, Garnet, French, and Borel Fires, will be particularly vulnerable to excessive runoff and debris flows. Several inches of snow will fall in the Sierra above 7,000 feet; the probabilities for at least three feet of snow are at around 75 to 85 percent with even greater chances over the highest peaks. This will allow a great start to this winter for Sierra Nevada snowpack. In addition, during this period, there will be a slight chance (10-20%) for thunderstorms.

Cool, unsettled conditions remain in our area into Friday into Saturday. Snow levels lower to around 4,000 to 5,000 feet during this period, which will bear watching, especially with any lingering showers that could pass over the mountain passes in Kern County. It appears we get some break in precipitation for late Saturday until Sunday. Models project a closed upper low that cuts off and brings some possibility of additional precipitation, though not as heavy, to Southern California and southern portions of our area sometime early next week.

The Climate Prediction Center shows a 40-50 percent chance of above average precipitation for the latest 8-14 day period, with slightly lesser chances for the 6-10 day period. Above average temperatures remain favored.

AVIATION

VFR/MVFR conditions will prevail until 06Z Wednesday. Gusty southerly winds developing with 15-20 kt winds and gusts reaching 22-30 kts after 00Z Wednesday across the San Joaquin Valley. Precipitation with MVFR to IFR ceilings develop over the Sierra Nevada and Kern County mountains after 00Z Wednesday combined with wind gusts 40-50 kts.

AIR QUALITY ISSUES

On Tuesday December 23 2025, Fireplace/Wood Stove Burning Status is: No Burning for All in Kern County. Burning Discouraged in Fresno, Kings, Madera, Merced, and Tulare Counties, 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

Flood Watch from Tuesday afternoon through Friday afternoon for CAZ300>317-319>322-327>339.

High Wind Warning from 4 PM Tuesday to 4 PM PST Thursday for CAZ333>339.

Wind Advisory from 4 PM Tuesday to 4 PM PST Thursday for CAZ300>304-308-309-313-314-316>318-324-332.

Flood Watch through Friday afternoon for CAZ318-323>326.

Winter Storm Warning until 10 PM PST Friday for CAZ323.

Winter Storm Warning from 4 PM Tuesday to 10 PM PST Friday for CAZ326>331.