Hurricane Hilary pounded Mexico then brought intense flooding to Southern California

Not quite a year after Tropical Storm Kay flooded parts of Southern California, towns and residents are cleaning up once again from copious amounts of rain thanks to Tropical Rainstorm Hilary, which turned deadly in Mexico.

Tropical Rainstorm Hilary formed on Aug. 16 off the coast of Mexico and underwent rapid intensification to become a Category 4 hurricane. On August 19, thunderstorms on the edge of Hilary, hundreds of miles away from the storm's center, caused severe flooding in Mulegé, Mexico, while one person near Santa Rosalia, Mexico, was killed by floodwaters. Both of those locations are on the east side of the Baja California Peninsula. Videos from Mulegé showed torrents of water running through the town.

Hilary moved ashore in Mexico's northern Baja California Peninsula as a tropical storm late in the morning of Aug. 20.

The wide-reaching storm closed parks and stymied air travelers in three states. Las Vegas declared a state of emergency Sunday, and all state beaches and parks were closed in Orange and San Diego counties. Governor Newsom of California proclaimed a state of emergency on Saturday as Hilary approached. Flooding in Ocotillo, California, was recorded by storm chasers early Sunday afternoon. Over 1,000 flights were canceled on Sunday, and Los Angeles, the nation's largest school district, was closed on Monday.

New rainfall records were set in Los Angeles, which had its rainiest summer day for the weather station downtown at 2.82 inches. San Diego did the same, totaling 1.82 inches of rain, 10 times the average summer total. As much as 10.51 inches of rain fell near Forest Falls, California, from Hilary, and many mountain rain gauges reported 8 to 9 inches.

The city of Palm Springs, California was temporarily isolated by flooding and 911 service was down on Monday morning, CNN reported.

According to reports from the National Weather Service Sunday afternoon, boulders were reported on roadways in San Bernardino County, and semi-trucks had flipped over on Interstate 8 near Gordon's Well, California.

Tens of thousands of power customers in California were without power from the storm on Sunday, peaking at 57,000 Monday morning. Winds were clocked above 80 mph in Mexico and the mountains of Southern California.

To add insult to injury, at 3 p.m. PDT on Aug. 20, a magnitude 5.1 earthquake was reported in Ojai, California, northwest of Los Angeles, where shaking was felt. No damage was reported. The earthquake was the strongest at that location since 1941.

Hurricane Hilary's track into Southern California was unusual. Primarily due to colder waters, which are similar to Atlantic Canada in August, tropical storms don't typically survive intact when they approach the state. In fact, this was only the second time a tropical storm was officially tracked over Southern California. In 1997, Hurricane Nora was tracked as a tropical storm in the easternmost part of the state. Official records began in 1949, but 10 years earlier, a likely tropical storm made landfall at Long Beach, California.

This image of Hilary was captured as the hurricane was near peak strength as a Category 4 storm several hundred miles off the coast of Mexico on Friday morning, Aug. 18, 2023. (NOAA Satellite)