California Braces for Record Heat as El Niño Fuels Heat Dome

WHO:

Sacramento Bee - Hurricane Genevieve, a Category 5 hurricane, is mentioned as influencing the weather conditions in California.

CNN - The National Weather Service is cited regarding heat alerts and health risks associated with the heat wave.

WHAT:

Sacramento Bee - A heat dome, described as the largest on Earth, is set to affect Southern California, leading to feels-like temperatures above 100 degrees.

Sacramento Bee - High temperatures in the Central Valley are expected to reach triple digits, with highs approaching 110 degrees near Bakersfield and Redding.

CNN - Death Valley, California, is forecasted to experience a blistering temperature of 126 degrees during the heat wave.

CNN - Around 40 million people are under heat alerts across the western United States.

CNN - Billings, Montana, is forecasted to hit 106 degrees, breaking its August record.

CNN - Maricopa County, home to Phoenix, has reported 40 confirmed heat-related deaths so far this year.

WHERE:

Sacramento Bee - The heat dome will be centered over Southern California and extend into the Central Valley.

CNN - The heat wave will affect areas from Southern California to Canada, including states in the western United States.

WHEN:

Sacramento Bee - The heat dome is expected to be over the southwestern US on Friday.

CNN - The heat wave is predicted to last from Friday through Tuesday.

CNN - By August 4, around 10% of the continental US will record the hottest day of the year so far.

WHY:

Sacramento Bee - The heat dome is partially strengthened by Hurricane Genevieve, which has drawn moisture and heat from the ocean.

CNN - Human-caused climate change is cited as a factor making heat waves more likely and intense.

HOW:

CNN - Heat domes act like a lid on a pot, trapping and enhancing hot air beneath them, which raises surface temperatures.

CNN - The heat wave is exacerbating wildfire risks and water concerns across the West, particularly in the Colorado River Basin.

(UPDATED July 31, 2026 06:07 UTC)

A significant heat wave is sweeping across the western United States, driven by a massive heat dome centered over Southern California, which is expected to bring feels-like temperatures above 100 degrees. With around 40 million people under heat alerts, areas like Death Valley are forecasted to reach a blistering 126 degrees, while the Central Valley could see highs nearing 110 degrees near Bakersfield and Redding. This extreme weather, partially influenced by Hurricane Genevieve, is predicted to last from Friday through Tuesday, with August 4 marking a potential record-breaking day for about 10% of the continental U.S.