448 FXUS66 KHNX 091620 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 920 AM PDT Mon Jun 9 2025 .KEY MESSAGES... 1. Expect gradual warming through midweek with Moderate Heat Risk for much of the lower elevations. 2. There is a 10 to 20 percent chance for thunderstorms in the Sierra Nevada this afternoon and evening. Lesser chances are in store afterward. 3. A minor cooling trend arrives later this week, then expect steady and seasonably warm temperatures into the weekend. && .DISCUSSION...A ridge of high pressure is building off the coast, per latest satellite imagery. This ridge will slowly work its way near the coast and will allow for gradual warming the next couple of days. Triple digit heat remains a possibility for the San Joaquin Valley until Wednesday (at a 30-70 percent chance), with the best chances on Tuesday. As for the desert, highs of 105 degrees have a moderate to high chance of occurrence (also around a 30-70 percent chance), with the best chances in the Indian Wells Valley in northeastern Kern County. Another opportunity for thunderstorms in the Sierra Nevada will begin this afternoon and continue into the early evening. Chances for this activity lower to 5-10% Tuesday onward, as a drier airmass arrives. A Moderate Heat Risk lasts until Wednesday, at least in the Central Valley. However it will persist until the weekend in the Kern County desert. Temperatures will lower by Thursday, with some locally gusty winds possible towards Pacheco Pass where there is about a 30-40 percent chance of a gust reaching 40 mph on Thursday and Friday. It appears highs in the lower to mid-90`s are more favorable for the SJ Valley, and the chances for a high below 90 degrees have lowered considerably (or to 15-30 percent for Friday into the weekend). Temperatures in the Kern County desert remain quite hot through the weekend, or with a 30-70 percent chance of continued triple digits. Also, the CPC is now showing near to above average temperatures for the region, according to their latest 6-10 and 8-14 day outlooks. && .AVIATION... 18Z Update: VFR conditions will prevail for the next 24 hours across the Central California Interior. A 15-25 percent chance of thunderstorms exists in the Sierra Nevada from 18Z Monday until 03Z Tuesday. && .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. && $$ BSO/EW weather.gov/hanford