Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
Issued by NWS San Joaquin Valley, CA
544 FXUS66 KHNX 010607 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1107 PM PDT Wed Sep 30 2026 && .KEY MESSAGES... 1. Above normal temperatures are expected in our area today, and temperatures will continue to warm through the end of the week. 2. A Moderate Heat Risk through the Central Valley is likely (50-70% chance) by Thursday with the chances increasing even further this weekend. && .DISCUSSION... A ridge of high pressure will continue to strengthen over the southwest, leading to further warming into tomorrow and the weekend where highs are expected to be 10 to 15 degrees above normal in the San Joaquin Valley. A very weak cut-off low is likely to pass over northern California by Monday, which will slightly lower highs in the Valley by a couple degrees, but widespread Moderate Heat Risk will be maintained from Friday through at least next Wednesday. The peak of the ridge is expected to be this weekend, particularly on Sunday, where chances for triple digits are 60-80% in the southern Valley and 40-60% in the northern Valley. And while triple digit chances decrease from Monday onwards, highs are likely to still be in the upper 90`s through the middle of the week. Looking to the long term forecast through day 10, temperatures may begin to decrease once again by late next week into next weekend, as a potential trough may move through Northern California. Modeled highs at that time would still remain above normal, but in the lower 90`s rather than the upper 90`s. Which is also likely why the Climate Prediction Center maintains the 80-90% chance of above normal temperatures for the region for days 8 to 14. && .AVIATION... VFR conditions will prevail for the next 24 hours. && .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. && $$ EW weather.gov/hanford