If you’re caring for an older parent, a young child or anyone with a chronic health condition, the next three days demand your attention. A dangerous heat wave is settling over the San Joaquin Valley — one strong enough that overnight temperatures won’t drop far enough to give bodies a real chance to recover.
The National Weather Service office in Hanford has issued a heat advisory for the San Joaquin Valley and adjacent foothills from noon Saturday through Monday evening. That’s roughly 60 hours of sustained, cumulative heat stress across Fresno, Merced, Bakersfield, Visalia, Madera and Hanford.
Afternoon highs are expected to reach 108 degrees in portions of the Valley, with widespread highs around 105. The NWS HeatRisk index — the scale designed to measure how dangerous heat is to human health, especially for vulnerable populations — ranges from moderate to major across the region.
Why this heat wave is different
The largest heat dome on Earth will be right over the southwestern US this Friday.Partially strengthened by Hurricane #Genevieve, temps will soar into the triple digits for an extended stretch across central California into next week. #cawxpic.twitter.com/7m6MONON80
— Sean Macaday (@MacadayWX) July 30, 2026
Two words to know: heat dome. Meteorologists say the largest heat dome on Earth will be parked over the southwestern United States starting Friday, pushing hot, high-pressure air down toward the ground and clearing the skies that would normally offer any relief…