027 FXUS66 KHNX 051806 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1106 AM PDT Sat Jul 5 2025 && .KEY MESSAGES... 1. Temperatures slightly below season normals will extend across the region today before a gradual warm up through the upcoming week. 2. Low RH values 15 to 25 percent will stretch across much of the San Joaquin Valley and Sierra Nevada this weekend with values 5 to 10 percent in the Mojave Desert. RH will decrease over the region later in the week with warming temperatures. && .DISCUSSION... A broad trough of low pressure continues to bring below normal temperatures to central California for today, though as the new week approaches, the system will gradually drop southward along the coast, becoming cutoff from the main upper level flow. Southwest winds will propagate over the region in the early part of the week, causing temperatures to warm near normal with highs in the upper 90s. However, as the week progresses, a ridge of high pressure currently located over the Four Corners is expected to slide westward and set up over central and southern California. There is a 40 to 80 percent chance for triple-digit temperatures in the valley areas on Thursday and a 60 to 90 percent chance on Friday, with the latter temperatures approaching 105 degrees. The desert areas including Inyokern and Ridgecrest have a 20 to 50 percent chance to exceed 110 degrees. RH values through the week will be fairly typical for this time of year, holding steady between 15 and 25 percent for the San Joaquin Valley and Sierra Nevada, and between 5 and 10 percent for the Mojave Desert. Though, with the warming temperatures in the latter part of the week, min RH values are expected to fall to 10 to 15 percent for the aforementioned valley and mountain areas. These values will continue the risk for grass fire development, however with the subsiding air aloft, winds will be relatively light in the valley areas, and mainly diurnal and terrain driven in the foothill, mountain, and desert areas. && .AVIATION... 18Z Update: VFR conditions will prevail for the next 24 hours across the Central California Interior. && .AIR QUALITY ISSUES... ISSUED: 07/04/2025 15:35 EXPIRES: 07/05/2025 23:59 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/aviation...McCoy weather.gov/hanford