Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
162 FXUS66 KHNX 041744 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 944 AM PST Thu Dec 4 2025 .KEY MESSAGES... 1. Fog and low clouds will continue each night and morning across the San Joaquin Valley for the remainder of this 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... The stratus deck persists over the Central Valley, although latest satellite imagery shows at least partial clearing towards the southern San Joaquin valley, such as in Kern County. Visibility has been 2 miles or better throughout the Central Valley with ceilings near 1,000 feet this morning. However, reports of dense fog and reduced visibilities have been received for locations within the cloud deck, including Interstate 5 through the Grapevine and Pacheco Pass. Webcams in the lower Sierra Nevada foothills also show dense fog. Any locations where clouds are clearing will likely become foggy by later tonight; latest high resolution ensemble guidance shows a 60-70 percent chance of visibility less than one quarter of a mile over the San Joaquin Valley. This pattern will continue for the next several days with a gradual rise in daytime high temperatures in the mountains and desert, or a rise to at least a few degrees above average by the weekend. Additional warming will continue into next week with highs rising to the lower 70`s at the warmest locations in the desert. Some rise in temperatures is shown for the San Joaquin Valley next week, but it will depend on the presence of fog and stratus. The Climate Prediction Center continues to show high probabilities (80-90%) of above average temperatures and a 50-60 percent chance of continued below average precipitation for the next 6-10 days. The 8-14 day outlook shows up to a 40 percent probability of below average precipitation and lower chances (60% to around 70%) for above average temperatures. && .AVIATION... MVFR visibility and ceilings will persist across the San Joaquin Valley through this afternoon. VFR conditions are expected elsewhere. A 30-50 percent chance of VLIFR conditions due to fog returns after 09Z Friday; otherwise expect IFR conditions at the TAF sites. Between 12Z and 18Z Friday...a 60-70 percent chance of VLIFR visibility and ceilings will exist across the San Joaquin Valley. && .AIR QUALITY ISSUES... On Thursday December 4 2025, Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno, Kern, Kings, Madera, and Tulare Counties. Burning Discouraged in Merced County, and 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 11 AM PST this morning for CAZ335. && $$ BSO weather.gov/hanford