Editor's Note:Read our coverage of Hurricane HilarySaturday here.
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Concerns are growing that Hurricane Hilary will unleash a prolific amount of rain that will flood the southwestern United States and parts of California as it moves across the region on Sunday and early next week, triggering a storm warning tropical to parts of Southern California.
Hilary could get away with more than onethe amount of rain in the yearin parts of three states: California, Nevada and Arizona. Because of the threat, parts of California face a rare and high risk of excessive rainfall. This Level 4 of 4 threat is the first to be issued for this part of Southern California.
Hilary was a powerful Category 4 hurricane that churned about 325 miles south of Cabo San Lucas, Mexico, on Friday afternoon with sustained winds of 130 mph with higher gusts,National Hurricane Centersaying.
The storm underwent incredibly rapid intensification Thursday into Friday, going from a tropical storm to a Category 4 hurricane in just 24 hours. Hilary is expected to remain a Category 4 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 the center of Hilary approaches over the weekend.
one leftwide range of resultsfor the strongest winds in the US as the storm moves north over the next few days. Small deviations in the hurricane's path can change the forecast for more intense rain and wind.
The hurricane is moving faster than expected, so Mexico and California are also expected to see impacts sooner than early predictions indicated. The center now expects the core of Hilary to be "very close to central Baja California on Saturday evening and will move inland over southern California on Sunday evening."
The NHC also noted that strong winds and heavy rain will hit areas long before they see the hurricane's center.
Hilary will most likely make landfall in Mexico and cross into California, but if it makes landfall in California as a tropical storm, it would be the first such storm to make landfall in California in nearly 84 years, according to data from National Oceanic year. and Atmospheric Administration.
The first tropical storm watch was issued for parts of Southern California on Friday morning, the National Hurricane Center said, stretching from the California-Mexico border to Los Angeles County. The warning was changed to a warning in an update Friday night.
"The threat of significant wind impacts continues to increase in the northern parts of the Baja California Peninsula and the southwestern United States, particularly in areas of mountainous terrain," the hurricane center said.sayingThursday evening.
Southwest braces 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 at the beginning of next week, with the heaviest downpours likely on Sunday and Monday.
It is difficult to overestimate the importance of the high risks of excessive rainfall. High risks are issued on less than 4% of days per year on average, but are responsiblefor 83% of all flood-related injuries and 39% of all flood-related deaths, according to research from the Center for Meteorological Prediction.
Parts of Southern California and Nevada could receive 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 Hilary, "there could potentially be several years of precipitation in some of the driest parts of California," Daniel Swain, a climate scientist at the University of California, Los Angeles, said Wednesday.
Among these places, Death Valley, California is the hottest place on Earth. Death Valley typically gets about 2 inches of rain in an entire year, according to NWS data. Hilary's moisture could release enough rain to give Death Valley a 1-2 years the amount of precipitation in a single day. And Las Vegas could get 2 to 4 inches of rain. It only averages 3.75 inches of rain per year.
Prolonged rain can saturate the soil and overwhelm waterways, potentially exacerbating the threat of flooding.
The Mojave National Preserve, 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.
National Weather Service i Los Angeleshave 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 Greater Los Angeles area is home to about 75,000 homeless people, with more than 46,000 within the city limits, according to a 2023 estimate fromLos Angeles Homeless Services Authority. California is generally home tohalf of all Americans without shelteraccording to federal data.
The county is reaching out to people, especially those staying in parks or near waterways, to provide temporary housing, Luna said. The sheriff's department is mapping the camps and making aerial announcements about the coming storm, as well as having outreach teams on the ground, he said.
"We hope the storm causes 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 are not affected, we will become a resource for other neighboring counties as needed."
Tropical activity increases in the Atlantic Ocean
Areas monitored by the National Hurricane Center to detect possible tropical development.
Not to be outdone by the eastern Pacific, the Atlantic is gearing up for a spectacular increase in tropical activity in the coming days. Four separate areas of concern span the entire basin from the western Cape Verde Islands to the Gulf of Mexico.
The most immediate concern for the United States is an area whereextremely hot Gulf of Mexicowhere weather conditions may converge to support tropical development next week. An area of low pressure could slowly organize in the basin, strengthen and become tropical over the western Gulf by midweek.
There are three distinct areas of concern in the tropical Atlantic. An area of scattered showers and thunderstorms west of the Cape Verde Islands may develop into a tropical depression over the weekend and may further strengthen into a tropical storm. Another area of weather disturbance just to the west could become a tropical depression early next week. However, another area has little chance of achieving tropical characteristics near the Lesser Antilles.
CNN's Eric Zerkel, Taylor Ward and Monica Garrett contributed to this report.