textproduct: San Joaquin Valley

UPDATE

Aviation Section Updated

KEY MESSAGES

1. Strong system moves in through Thursday bringing moderate rain and heavy snow to the region.

2. Winter Storm Warning in effect through 10 PM Wednesday for the Sierra Nevada and Kern Mountains.

3. 40 to 50 percent chance of an inch of snow in 24 hours ending 4 pm Wednesday along Tejon Pass has led to a Winter Storm Watch for the I-5/Grapevine area.

4. Strong wind gusts expected along area mountain ranges, along with the Mojave Desert and portions of the southern San Joaquin Valley. Wind Advisory in effect from 7 am Monday through 4 pm Wednesday for the West Side Hills and Mojave Slopes and from 7 AM through 7 PM Monday for the southern San Joaquin Valley.

5. Slight risk of severe thunderstorms in portions of Merced County with a 2 to 4 percent chance of tornadoes. General risk of thunderstorms for much of the remainder of the Valley.

DISCUSSION

The radar this afternoon has detected the rain beginning to again move into the Bay Area and portions of the coastal range as the first big trough begins moving in. The bulk of the precipitation from this first wave begins later this evening and into Monday. Latest probabilities have a 55 to 80 percent chance of half an inch or more of rain in 24 hours in the Valley ending 10 pm Monday. However, high resolution convective allowing models are showing the potential for thunderstorms with a 30 to 60 percent chance of CAPE values of 100 J/kg Monday afternoon across the Valley along with a 30 to 50 percent chance of surface to 1 km helicity of at least 100 m^2/s^2. This has led the SPC to issue a Marginal risk of severe thunderstorms with a 2 to 4 percent chance of tornadoes in portions of Merced County and a general risk of thunderstorms for most of the remaining portion of the Valley.

However, the big concern with the storms this week is the snow especially as a stronger, colder second trough slides through Tuesday into Wednesday lowering snow levels drastically to 2,000 to 2,500 feet by 7 am Wednesday. The best case (low end) snow amounts shows a 90 percent chance of 2 to 3 feet of snow above 5,000 feet and 3 to 4 feet above 7,000 feet. On the other extreme, the worst case shows 5 to 6 feet above 5,500 feet and 6 to 8 feet above 7,000 feet. The lowering snow elevations also brings the potential for snow on the passes as there is a 21 percent chance of 4 inches of snow on Tejon Pass and a 5 to 20 percent chance of 4 inches of snow on Tehachapi Pass. There also is a 5 to 10 percent chance of a trace even in the Valley.

This second push also will bring a second pulse of rain into the Valley with a 45 to 60 percent chance of another half an inch of rain ending 4 PM Wednesday for the Valley. As the trough lifts on Thursday and Friday, a shortwave trough slides across northern California bringing another chance of showers, but lighter. Temperatures will remain below average heading into the weekend. In the long term, the CPC shows a change. The temperature outlooks go from a 33 to 40 percent chance of below average temperatures in the 6-10 day outlook to near normal in the 8-14 day outlook. Both the 6-10 and 8-14 day outlooks continue to favor above average precipitation at 40 to 50 percent for the Valley.

AVIATION

CIGs begin to lower around 09Z to 12Z to FL050 from FL100. Precipitation is expected to enter the TAF sites around 06Z Monday before extending after 09Z through the rest of the period. MVFR conditions begin to be possible after 15Z Monday in heavier showers lowering visibility. IFR to MVFR conditions possible in the mountains after 09Z due to increasing clouds and the precipitation. There is a 10 to 20 percent chance of thunderstorms after 18Z. Otherwise, VFR conditions will prevail.

AIR QUALITY ISSUES

ISSUED: 02/15/2026 14:05 EXPIRES: 02/16/2026 23:59

On Monday February 16 2026, Fireplace/Wood Stove Burning Status is: Burning Discouraged in Fresno, Kern, 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

Wind Advisory from 7 AM Monday to 4 PM PST Wednesday for CAZ300-308-313-337>339. Wind Advisory from 7 AM to 7 PM PST Monday for CAZ309-310- 314>316. Winter Storm Warning until 10 PM PST Wednesday for CAZ318-320- 322>331-333-334-336. Winter Storm Watch from Monday afternoon through Thursday morning for CAZ335.