Hurricane Hilary grew quickly to a Category 4 storm off Mexico's Pacific coast on Friday. It could hit Southern California as the first tropical storm there in 84 years, causing "significant and rare impacts" like widespread flooding.
Hilary had steady winds of about 145 mph (230 kph), according to the U.S. National Hurricane Center. It was expected to keep getting stronger quickly until Friday, when it would start to weaken. It will still be a hurricane when it gets close to the region of Baja California in Mexico on Saturday night, but it will be a tropical storm when it gets close to Southern California on Sunday.
The National Weather Service says that since September 25, 1939, no tropical storm has hit land in Southern California. Before that, the San Diego storm hit land in October 1858. Research shows that this was the only time a storm hit California.
Nora, which hit California in 1997, was the last and only other tropical storm to keep its name after getting there. The latest forecast also says that Hilary will still be a tropical storm when it gets to Nevada, which has never happened before.
Early on Friday, Hilary was about 400 miles (640 kilometers) south of Los Cabos, which is at the southern tip of the Baja peninsula. It was moving west-northwest at 13 mph (20 kph), but through Saturday, it was predicted to slowly turn to the north.
The Mexican government put out a hurricane watch and a tropical storm warning for parts of Baja California Sur in the north. They also put out a tropical storm watch for parts of the Mexican mainland.
The hurricane center said that Hurricane Hilary will bring heavy rain to the Southwestern U.S. until next Wednesday. The rain will be heaviest on Sunday and Monday. It said there was a big chance of flash flooding from San Diego to Las Vegas.
The Mexican government said that a weaker version of Hurricane Hilary could hit the coast between Playas de Rosarito and Ensenada in Baja California State on Sunday night.