Hurricane Hilary: 'catastrophic, life-threatening flooding' potential for Mexico and California

Still roaring Saturday morning, Hurricane Hilary was headed to Mexico and California as authorities warn the storm could bring "catastrophic and life-threatening flooding." 

Hilary is expected to plow into Mexico Saturday night and then surge northward to Southern California as a tropical storm. It's already made history as the first-ever Tropical Storm Watch was issued by The U.S. National Hurricane Center for parts of California.

Officials as north as Los Angeles scrambled to get the homeless off the streets, set up shelters and prepare for evacuations.

Gov. Gavin Newsom was headed to Southern California Saturday and will be there for the next several days as the storm makes landfall.

"We should never underestimate the power of Mother Nature," said Newsom. "California is coordinating with federal and local governments to support communities as they prepare for this unprecedented storm." 

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SoCal residents can expect gusty winds, significant rainfall, and dangerous ocean and marine conditions. 

Between 2 and 4 inches of rain is expected in the coasts and valleys, between 3 and 7 inches of rain in the foothills and deserts, and between 4 and 10 inches of rain in the mountain communities. 

"People are a little uneasy," said Craig Herrera Saturday morning. "They've got one more day to make preparations for this storm."

After rapidly gaining power early Friday, Hilary slowed some later in the day but remained a major Category 4 hurricane early Saturday with maximum sustained winds of 130 mph (215 kph), down from 145 mph (230 kph).

I don’t think any of us — I know me particularly — never thought I’d be standing here talking about a hurricane or a tropical storm," said Janice Hahn, chair of the Los Angeles County Board of Supervisors.

Early Saturday, the storm was centered about 240 miles (390 kilometers) west-southwest of the southern tip of the Baja peninsula. It was moving north-northwest at 13 mph (20 kph) and was expected to turn more toward the north and pick up speed.

The latest forecast track pointed to Hilary making landfall along a sparsely populated area of the Baja peninsula at a point about 200 miles (330 kilometers) south of the Pacific port city of Ensenada.

It is then expected to continue northward, raising fears that its heavy rains could cause dangerous flooding in the border city of Tijuana, where many homes in the city of 1.9 million cling precariously to steep hillsides.

Associated Press contributed to this report.