textproduct: San Joaquin Valley

UPDATE

Aviation and Discussion sections updated.

KEY MESSAGES

1. Wind Advisory for the Mojave Slopes and Desert throuhg Saturday morning and lee side of the Coastal Range until Friday evening.

2. Lake Wind Advisory for Lake Isabella through Saturday morning.

3. A major cooling trend takes place Friday into the weekend and next week.

4. Winter Storm Warning in effect through Tuesday morning with up to 20 inches of snow expected above 6,000 feet in total.

5. Multiple storm systems on Friday through Friday night, Sunday night through Monday, and Wednesday through next Thursday bring much needed rain to the Central Valley and Sierra Nevada foothills.

DISCUSSION

The first of multiple areas of low pressure is expected to push through Central California this afternoon through Saturday morning, with the onset of precipitation arriving in Merced County around mid-day. Before discussing the precipitation, a mention of stronger winds is needed ahead of the approaching front. This morning, downsloping wind gusts along the lee (eastern) side of the Coastal Range have risen to 30-45 mph, necessitating the issuance of a Wind Advisory for the locations west of US Interstate 5. This advisory will be valid until 03Z (7 PM PST) this evening. Stronger winds will also extend into the Mojave Desert, initially moving out of the south to southwest, similar to the winds along the Coastal Range. However, after the front passes by early Saturday morning, winds will shift to the northwest, downsloping heavily along the Mojave Desert Slopes.

The aforementioned front will gradually track through the region this afternoon from north to south, resulting in widespread high probabilities (90 to 100 percent) for at least one-tenth of an inch over the next 24 hours. In fact, most locations along and east of SR 99 have high probabilities for one-quarter inch, and a moderate probabilitiy (60 to 70 percent) for one-half inch. Bakersfield is the odd man out, with just a moderate prob (50 to 60 percent) for one-tenth of an inch. There is also an expected rain shadow effect over the western valley areas as the stronger winds in the Coastal Range push the incoming moisture over this area, landing it in the eastern valley.

Snow levels with the frontal boundary are generally expected between 7500 to 8500 feet through Friday before falling near 5000 feet Saturday morning. Much of the moisture with the system will arrive Friday, when snow levels are relatively high, but lingering moisture into Saturday is enough to warrant a Winter Storm Warning for the Sierra Nevada above 6000 feet. 24 hour totals are expected between 3 to 5 inches at the latter elevation, rising to 5 to 10 inches up to 8000 feet, then up to 20 inches for the highest elevations. Bringing up winds again, maximum gusts through this evening along the crests are expected up to 50 mph, creating very difficult to impossible travel conditions due to snow amounts and blowing snow.

A brief repreieve is expected from the rain and snow for Saturday and most of Sunday before a second system arrives Sunday afternoon which will bring additional precipitation through Tuesday. Though a bit slower than the first system, precipitation amounts will be similar to those over this weekend. This active pattern looks to continue into next week as well, with a potential third system also on the horizon Wednesday into Thursday.

AVIATION

For the Sierra Nevada and San Joaquin Valley, mostly VFR conditions until 20Z-21Z Fri. MVFR to IFR conditions will gradually move in as rain and snow enters the region. Visibilities will gradually decrease from north to south. Will expect southeasterly winds 12-15 kts with gusts 20-25kts through at least 00Z Sat, with locally stronger gusts in the Mojave Desert and along the Sierra Crest. VFR conditions will prevail for the next 24 hours in the desert.

AIR QUALITY ISSUES

On Friday, November 13, 2026, Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno, Kern, Kings, and Tulare Counties. Burning Discouraged in Madera and Merced 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 until 7 AM PST Saturday for CAZ337>339. Wind Advisory until 7 PM PST this evening for CAZ300-304-308- 313-336. Winter Storm Warning until 4 AM PST Tuesday for CAZ323-325>330. Lake Wind Advisory until 10 AM PST Saturday for CAZ332.