California Heat Wave Shatters Records as Millions Under Alerts

A potent October heat wave is continuing to bake California, with at least 37 million people under heat alerts as of Sunday. Temperatures are forecast to climb 20 degrees above normal for this time of year, reaching into the 90s and 100s from the San Francisco Bay Area to the Mexico border.

Southern California is particularly affected, with an excessive heat warning in place for cities including Los Angeles, Riverside, and Temecula, where highs are expected to be in the triple digits. San Diego is also under an excessive heat warning, with temperatures projected to reach the upper 90s. These extreme heat warnings are set to remain in effect until 8 p.m. local time on Thursday.

On Saturday, multiple cities in Southern California broke daily high-temperature records. Anaheim and San Diego both reached 105 degrees, Santa Ana recorded 107 degrees, and Vista, north of San Diego, hit 108 degrees, tying an all-time record high for the location. In some urban areas, warm overnight temperatures are expected to offer little relief.

The hot weather is anticipated to spread eastward into the Great Basin in the coming days, with temperatures in the 80s and near 90s expected.

Elsewhere in the country, parts of the Gulf Coast and Southeast are experiencing unsettled weather with multiple rounds of heavy rain and thunderstorms. A flood watch is in effect for areas from Louisiana to Florida and Georgia. Sunday sees a level 2 of 4 risk for excessive rainfall and flash flooding from New Orleans into the Carolinas. The Florida panhandle and parts of the Gulf Coast, including Mobile, Alabama, and Biloxi, Mississippi, could see rainfall totals of 2 to 6 inches, with some localized areas potentially receiving 8 to 10 inches. The lower Texas coast faces a level 3 of 4 "significant" risk of excessive rainfall and flash flooding on Sunday, with possible rainfall rates of 1 to 2 inches per hour.