Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
290 FXUS66 KHNX 061206 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 406 AM PST Sat Dec 6 2025 .UPDATE... Updated Aviation Section. && .KEY MESSAGES... 1. Fog and low clouds will continue each night and morning across the San Joaquin Valley into early next week. Dense fog will also develop at times in the lower Sierra foothills, coastal ranges, and the Grapevine. 2. A gradual warming trend will occur in the mountains and desert until next week, as the high pressure pattern continues over the region. && .DISCUSSION... A ridge of high pressure will strengthen and move further inland. This will allow temperatures to rise, at least in the mountains and desert. However, fog and stratus will persist over the Central Valley as well as the coastal ranges, lower Sierra foothills, and the Kern County mountains for at least the next few days. Dense fog will continue at times tonight into Saturday along major highways, such as Interstate 5 through the Grapevine in Kern County and Highway 152 through Pacheco Pass. It is also possible dense fog will occur anywhere that the stratus deck touches the lower Sierra foothills and Tehachapi Mountains, including at elevations around 1,500 to 2,500 feet. Otherwise, the Central Valley may fog back up anywhere the stratus deck clears. Currently, short term high resolution guidance shows a 40-50 percent chance of dense fog anywhere in the Central Valley and lower chances (about 20-30 percent) towards the foothills and coastal ranges through the late morning hours on Saturday. This dry and stable pattern will last until next week and beyond. The latest CPC outlooks have the Valley, the Sierra Nevada, and the Mojave Desert under a 70 to 90 percent chance of above average temperatures due to the persisting ridge. However, the outlooks show a shift from a 40 to 50 percent probability of below average precipitation to a 33 to 40 percent probability of above average precipitation for the much of the Valley and Sierra Nevada. && .AVIATION... IFR ceilings and visibilities are expected to prevail through 20Z Saturday before improving to MVFR. LIFR conditions will also persist in the coastal ranges, Sierra foothills, and the Kern County mountains due to the low stratus deck. && .AIR QUALITY ISSUES... On Saturday December 6 2025, Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno, Kern, Kings, Madera, Merced, and Tulare Counties. Burning Discouraged in Kern (Greater Frazier Park Area) and Sequoia National Park and Forest. && .CERTAINTY... The level of certainty for days 1 and 2 is medium. 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... Dense Fog Advisory until noon PST today for CAZ300-335. && $$ public/aviation....BSO/EW weather.gov/hanford