Editor's note:Read our coverage of Hurricane Hilarysaturday here.
cnn—
Concerns are growing that Hurricane Hillary will unleash widespread flooding across the southwestern United States and parts of California as it moves through the region Sunday and early next week, prompting a tropical storm warning for parts of southern California. California.
Hilary could turn down more than onerain of the yearin parts of three states: California, Nevada and Arizona. Due to the threat, parts of California face a rare and high risk of excessive rainfall. This Level 4 of 4 threat is the first issued to this part of Southern California.
Hillary was a powerful Category 4 hurricane that struck about 325 miles south of Cabo San Lucas, Mexico, Friday afternoon with sustained winds of 130 mph with higher gusts.National Hurricane Centerhe said.
The storm underwent incredibly rapid intensification Thursday through Friday, going from a tropical storm to a Category 4 hurricane in just 24 hours. Hilary is forecast to remain a Category 4 storm as it approaches Mexico's Baja California peninsula through Saturday.
Forecasters have issued hurricane and tropical storm warnings and watches for Baja California, including the Los Angeles area, extending as far as Point Mugu in Ventura County and northwestern Mexico as it approaches central Hilary during the weekend.
one leftwide range of resultsfor the strongest winds in the US as the storm moves north over the next two days. Small deviations in the hurricane's path could change the forecast for more intense rains and winds.
The hurricane is moving faster than expected, so Mexico and California are also expected to see impacts sooner than initial forecasts indicated. The center now predicts that Hillary's core will be "very close to central Baja California on Saturday night and will move inland over southern California on Sunday night."
The NHC also noted that high winds and heavy rain will hit areas long before they see the center of the hurricane.
Hilary will most likely make landfall in Mexico and pass into California, but if it does make it to California as a tropical storm, it will be the first such storm to hit California in nearly 84 years, according to National Oceanic. and Atmospheric Management.
The first tropical storm watch was issued for parts of southern California Friday morning, according to the National Hurricane Center, which stretches from the California-Mexico border to Los Angeles County. The alert was changed to a warning in an update late Friday.
"The threat of significant wind impacts continues to increase in the northern parts of the Baja California peninsula and the southwestern United States, especially in areas of mountainous terrain," the hurricane center said.he saidThursday night.
Southwest Struts for Major Flooding
Hillary is expected to weaken significantly before reaching southern California and parts of the Southwest, but regardless of its strength, the storm will bring heavy rainfall and increase the risk of flooding.
Heavy rain is expected to begin affecting the Southwest on Saturday and into early next week, with the heaviest rains likely on Sunday and Monday.
It is difficult to overstate how high the risk of excessive rainfall is. High risks are issued on less than 4% of days per year on average, but are responsiblefor 83% of all flood-related damage and 39% of all flood-related deaths, shows an investigation of the Meteorological Prediction Center.
Parts of southern California and Nevada could see 3 to 5 inches of rain with isolated amounts up to 10 inches. Rainfall of 1 to 3 inches is expected in the central parts of these states, as well as western Arizona and southwestern Utah.
Thanks to Hillary, "several years of rain could fall in some of the driest parts of California," Daniel Swain, a climatologist at the University of California, Los Angeles, said Wednesday.
Among these places is Death Valley, California, the hottest place on Earth. Death Valley typically gets about 2 inches of rain over the course of an entire year, according to NWS data. Hilary's moisture could cause enough rain to give Death Valley a 1 for 2 years precipitation value in one day. And Las Vegas could get 2 to 4 inches of rain. It averages only 3.75 inches of rain per year.
Prolonged rains can over-saturate the soil and inundate waterways, potentially exacerbating the threat of flooding.
The Mojave National Refuge, which straddles the California-Nevada border, is closed until further notice due to possible flooding from the storm, spokeswoman Sierra Willoughby told CNN on Friday.
Flood watches have been issued over the weekend across Southern California, from San Diego to Los Angeles, as residents prepare for possible flooding.
The National Weather Service in Los Angeleshas also warnedof the potential for dangerously high surf, rip currents, and coastal flooding. Several county departments have spent the past few days preparing for the storm and have emergency personnel ready for an immediate response, Los Angeles County Sheriff Robert Luna said during a news conference Friday.
Luna said a major concern is protecting homeless members of the community. The Los Angeles metropolitan area is home to about 75,000 homeless people, with more than 46,000 within the city limits, according to a 2023 estimate from theLos Angeles Homeless Services Authority. California generally hostshalf of all Americans without insurance, according to federal data.
The county is reaching out to people, especially those who live in parks or near waterways, to provide temporary housing, Luna said. The sheriff's department is mapping the encampments and making aerial announcements about the coming storm, in addition to ground search teams, she said.
"We hope the storm will cause no damage and more importantly no loss of life," the sheriff said. "But we will prepare for the worst case scenario, not only to help people here in our county, but if we're not affected, we'll be a resource to other neighboring counties as needed."
Tropical activity increases in the Atlantic
Areas monitored for possible tropical development by the National Hurricane Center.
Not to be outdone by the eastern Pacific, the Atlantic is bracing for a spectacular increase in tropical activity in the coming days. Four distinct areas of concern span the entire basin from the western Cape Verde Islands to the Gulf of Mexico.
Of more immediate interest to the United States is an area in whichextremely warm Gulf of Mexicowhere weather conditions may combine to support tropical development next week. A zone of low pressures could slowly organize in the basin, strengthen and become tropical in the western Gulf by midweek.
There are three distinct areas of concern in the tropical Atlantic. An area of disorganized showers and thunderstorms west of the Cape Verde Islands could develop into a tropical depression over the weekend and could further strengthen into a tropical storm. Another area of disturbed weather just to the west could become a tropical depression early next week. Another region has little chance of acquiring tropical characteristics near the Lesser Antilles.
CNN's Eric Zerkel, Taylor Ward and Monica Garrett contributed to this report.