Hurricane Hilary 2023: Category 4 storm path has California bracing for heavy rain, floods

Hurricane Hilary is rapidly intensifying in the Pacific Ocean and could bring heavy rain and flash flooding to southern California and Nevada by the weekend, forecasters said.

The hurricane could potentially bring “significant impacts” to parts of the Baja California Peninsula and the southwestern United States this weekend, including rainfall of up to 12 inches in the Southern California mountains, according to the National Hurricane Center.

As of Friday morning, Hilary had maximum sustained winds of 145 mph and had reached Category 4 status, according to the hurricane center. It is forecast to be near or over the central Baja coast Sunday. Rain is forecast to begin arriving in Southern California starting Sunday night.

Friday updates: Hurricane Hilary tracker, map as storm moves toward U.S.

Hurricane Hilary on NOAA satellite Thursday afternoon. Hilary is expected to make landfall over or near the Baja California Peninsula on Sunday, then move over California as a tropical storm or depression on Sunday night and Monday.
Hurricane Hilary on NOAA satellite Thursday afternoon. Hilary is expected to make landfall over or near the Baja California Peninsula on Sunday, then move over California as a tropical storm or depression on Sunday night and Monday.

Hilary could be the first tropical storm to make landfall in California since 1939, according to federal weather officials. Tropical Storm Kay brought heavy rain and flooding to Southern California last year despite not making landfall.

"The combination of heavy rainfall, the potential for flash flooding, and strong winds could very well make this a high impact event for Southern California," Samantha Connolly, a National Weather Service meteorologist in San Diego, wrote in a Thursday morning forecast.

A man moors his boat in Acapulco, Guerrero State, Mexico, on August 16, 2023, following the passage of Tropical Storm Hilary.
A man moors his boat in Acapulco, Guerrero State, Mexico, on August 16, 2023, following the passage of Tropical Storm Hilary.

The hurricane center doesn't rule out a landfall farther in California.

"Although there is fairly high confidence in the track prediction, Hilary's oblique angle of approach to the west coast of the Baja California peninsula makes it nearly impossible to know at this point if the center will remain just offshore or move over the peninsula before reaching the southwestern United States," Richard Pasch, a senior hurricane specialist at the center wrote in a Thursday forecast.

How much rainfall could Hurricane Hilary bring?

Hilary is expected to bring a risk of flash flooding and heavy rainfall in southern California, southern Nevada and western Arizona, the hurricane center said. Here's the weather service rain forecast for California, in inches.

  • Coast/Valleys: 2-2.5

  • Mojave Desert: 3-5

  • Mountains: 4-10, with up to 12 inches on the eastern mountain slopes

  • Lower Deserts: 4-7

The most rainfall ever recorded during the month of August in San Diego was 2.13 inches in 1977, the weather service said Thursday.

Daniel Swain, a climate scientist at the Institute of the Environment and Sustainability at the University of California, Los Angeles, said he is "increasingly concerned" regarding the potential for widespread and potentially severe flash flooding across interior portions of southern California and Nevada on Sunday and Monday.

The greatest concern would be east-facing slopes, but even lower deserts could see "extremely heavy rainfall," Swain posted on X, formerly Twitter.

Here's a look at Hurricane Hilary's expected path:

Hurricane Hilary path tracker 2023

Specific Storm Map:

Hurricane Hilary sphagetti model

This article originally appeared on USA TODAY: Hurricane Hilary path tracker: California braces for Category 4 storm