Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
531 FXUS66 KHNX 162051 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 151 PM PDT Thu Oct 16 2025 .UPDATE... Updated key messages section. && && .KEY MESSAGES... 1. Fog development expected for the San Joaquin Valley (along the Highway 99 corridor) Friday (50-60% chance for quarter mile visibility) and Saturday (30-40% chance for quarter mile visibility). 2. Drier and calmer conditions will prevail from this Wednesday and into the weekend before another trough slides in next Monday. 3. Probability of reaching 75 degrees will rise to 60% to 80% by Friday with a 20% to 40% chance of reaching 80 degrees during the weekend. && .DISCUSSION... Quiet weather now expected to dominate the region with warming temperatures and spotty morning fog favored across Central California. With the storm producing widespread 1 to 2 inches of rain (1 to 2 feet of snow), low level humidity now able to support fog generation as the threat will exist during the early morning hours. This pattern will persist through at least the end of the week. A ridge of high pressure pushing onto the West Coast will allow for a warm-up as temperatures return to near normal values during the weekend. Probability of Exceedance of reaching 80 degrees shows a steady rise with percentages near 60 percent by Saturday. During the same time frame, the west side of the San Joaquin Valley shows a range of 70% to 90% which increases confidence in that area able to reach the 80 degree mark. In terms of fog development, ensemble visibility analysis shows the best timing of fog near sunrise for at least the next two mornings. Probability of having visibility drop below 2 miles ranges from 60% to 70% for Friday morning. For the same period, the probability of falling below one quarter mile is to 50% to 60%. Current projections has the next disturbance near Yosemite by Monday afternoon with the bulk of the disturbances energy remaining north of Central California. && .AVIATION... VFR conditions will prevail across the central California interior through 09Z Fri. Areas of patchy fog developing in the San Joaquin Valley approaching 12Z. 30 to 50 percent chance for IFR conditions or less at KFAT, KMER, KMCE, and KVIS until 18Z. && .AIR QUALITY ISSUES... None. && .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... None. && $$ public...Molina aviation....McCoy weather.gov/hanford