Tropical Storm Hilary strengthens, ‘significant’ flooding, rain impacts possible for California, Southwest

Heavy rain from Tropical Storm Hilary is expected to bring a risk of flash flooding across Southern California and the Southwest on Saturday, Sunday and Monday.

As of Thursday at 8:00 A.M., Hilary rapidly intensified into a hurricane. Continuous coverage of Hurricane Hilary has moved here.

Tropical Storm Hilary continues to intensify and is expected to become a hurricane within a matter of hours off the southwestern coast of Mexico as forecasters warn the impacts of the large storm could be significant across portions of Southern California and the Southwest starting this weekend as heavy rain could bring the risk of flooding.

"Hilary has the potential to bring significant impacts to the Baja California Peninsula and portions of the southwestern United States this weekend and early next week, including after it becomes post-tropical," the National Hurricane Center (NHC) said in its latest advisory.

A cyclone is declared a tropical storm when maximum sustained winds reach at least 39 mph, and much like its fellow tropical depressions and hurricanes, impacts can be significant.


Here's a closer look at Tropical Storm Hilary.

The wind field of Tropical Storm Hilary.
(FOX Weather)


Where is Tropical Storm Hilary?

Tropical Storm Hilary is located about 330 miles to the south-southwest of Manzanillo, Mexico, and about 620 miles to the south-southeast of Cabo San Lucas, Mexico. It is moving to the west-northwest at 13 mph.

Tropical Storm Hilary has maximum sustained winds of 70 mph with higher gusts, and the NHC says rapid strengthening is forecast and Hilary will likely become a hurricane "very soon" and could become a major hurricane (Category 3 strength or higher) by Thursday night or early Friday.


The latest information on Tropical Storm Hilary.
(FOX Weather)


What is the forecast for Tropical Storm Hilary?

The NHC says that while Tropical Storm Hilary is moving to the west-northwest, a turn to the northwest is expected by Friday morning, followed by a turn toward the north-northwest and then north on Saturday.

On that forecast track, the NHC says Tropical Storm Hilary will approach the Baja California peninsula over the weekend.


The forecast track for Tropical Storm Hilary.
(FOX Weather)


What are the impacts of Tropical Storm Hilary?

The Mexican government has issued Tropical Storm Watches for the southern portion of Baja California Sur from Cabo San Lazaro southward on the west coast and San Evaristo southward on the east coast.

A Tropical Storm Watch is issued when tropical storm winds (39 mph to 73 mph) are possible in the watch area within 48 hours.

Additional Tropical Storm Watches or Tropical Storm Warnings will likely be issued later on Thursday, according to the NHC.

Tropical Storm Watches in effect until further notice.
(FOX Weather)


Large swells generated by Tropical Storm Hillary will affect portions of the coast of southwestern Mexico and the Baja California Peninsula over the next few days. Those swells, according to the NHC, are likely to cause life-threatening surf and rip currents.

As Tropical Storm Hilary spins closer to the U.S.-Mexico border, millions of people living in Southern California and the Southwest will need to keep an eye on a surge of tropical moisture expected to impact the region.

When to get ready for the storm.
(FOX Weather)


Tropical Storm Hilary is expected to produce rainfall amounts of 3-6 inches, with isolated amounts of 8 inches, across portions of the Baja California Peninsula through Monday morning. Flash flooding, which could be significant, will be possible.

Heavy rain associated with Tropical Storm Hilary is also expected to impact California and the Southwest starting Friday and lasting through early next week, with peak impacts expected on Sunday and Monday.


Forecast rain totals in California and the Southwest from Sunday, August 20, through Wednesday, August 23, 2023.
(FOX Weather)


Southern California, including Los Angeles and San Diego, could see several inches of rain through Wednesday. Amounts totaling 3-5 inches are forecast for portions of southeastern California and portions of southern Nevada. Locally higher amounts between 5-8 inches are also possible.

Between 2 and 3 inches of rain are possible in portions of western Arizona.

The flash flood threat of Tropical Storm Hilary on Saturday, Sunday and Monday.
(FOX Weather)