What are California's Santa Ana winds?

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What are California's Santa Ana winds?

2025-01-08 02:51 Last Updated At：03:01

LOS ANGELES (AP) — Santa Ana winds are common in Southern California during cooler months. Here’s a look at the often-fierce winds that topple power lines and trees and can turn a spark into a raging wildfire:

Santa Anas are dry, warm and gusty northeast winds that blow from the interior of Southern California toward the coast and offshore, moving in the opposite direction of the normal onshore flow that carries moist air from the Pacific into the region.

Santa Anas are created by high pressure over the Great Basin — the vast desert interior of the West overlapping several states. The sinking air loses its moisture and flows in a clockwise direction toward Southern California, where it must get past towering mountain ranges that separate the desert from the metropolitan region lining the coast. Like a slow-moving river that suddenly narrows and turns into rapids, the air speeds up as it squeezes through mountain passes and canyons, becoming drier and warmer as it descends.

Humidity levels often plunge to single-digit percentages during a Santa Ana wind. The extreme lack of humidity in the air causes vegetation — living and dead — to significantly dry out and become susceptible to fire. The tremendous wind speeds can stoke any spark — from a fallen power line, for example — into a rapidly spreading conflagration. Santa Anas are linked to some of the worst wildfires Southern California has experienced.

A commonly accepted explanation is that the name is linked to Santa Ana Canyon in Orange County. Other theories persist, along with other nicknames such as “devil winds.”

Santa Ana winds can sweep urban pollution away, creating sparkling vistas. At the same time, the extreme lack of moisture dries out lips, noses, throats and skin. In the short story “Red Wind,” Raymond Chandler captured the emotional effect: “There was a desert wind blowing that night. It was one of those hot dry Santa Anas that come down through the mountain passes and curl your hair and make your nerves jump and your skin itch."

South and Midwest pounded by rains and floods while still reeling from tornadoes

2025-04-05 10:06 Last Updated At：10:11

HOPKINSVILLE, Ky. (AP) — Torrential rains and flash flooding battered parts of the Midwest and South on Friday, killing a boy in Kentucky who was swept away as he walked to catch his school bus. Many communities were left reeling from tornadoes that destroyed entire neighborhoods and killed at least seven people earlier this week.

Round after round of heavy rains have pounded the central U.S. for days, and forecasters warned that it could persist through Saturday. Satellite imagery showed thunderstorms lined up like freight trains over communities in Arkansas, Tennessee and Kentucky, according to the national Weather Prediction Center in Maryland.

In Frankfort, Kentucky, a 9-year-old boy died in the morning after floodwaters swept him away while he was walking to a school bus stop, Gov. Andy Beshear said on social media. Officials said Gabriel Andrews' body was found about a half-mile from where he went missing.

The downtown area of Hopkinsville, Kentucky — a city of 31,000 residents 72 miles (116 kilometers) northwest of Nashville — was submerged. A dozen people were rescued from homes, and dozens of pets were moved away from rising water, a fire official said.

“The main arteries through Hopkinsville are probably 2 feet under water,” Christian County Judge-Executive Jerry Gilliam said earlier.

Tony Kirves and some friends used sandbags and a vacuum to try to hold back rising waters that covered the basement and seeped into the ground floor of his photography business in Hopkinsville. Downtown was “like a lake,” he said.

“We’re holding ground,” he said. “We’re trying to maintain and keep it out the best we can."

A corridor from northeast Texas through Arkansas and into southeast Missouri, which has a population of about 2.3 million, could see clusters of severe thunderstorms late Friday. The National Weather Service’s Oklahoma-based Storm Prediction Center warned of the potential for intense tornadoes and large hail.

The seven people killed in the initial wave of storms that spawned powerful tornadoes on Wednesday and early Thursday were in Tennessee, Missouri and Indiana.

Tennessee Gov. Bill Lee said entire neighborhoods in the hard-hit town of Selmer were “completely wiped out” and it was too early to know whether there were more deaths as searches continued.

A flash flood emergency was issued Friday night in Van Buren, a small city in southeastern Missouri. The NWS office in Paducah, Kentucky, said there were at least 15 water rescues.

Heavy rains were expected to continue in parts of Missouri, Kentucky and elsewhere in the coming days and could produce dangerous flash floods. The weather service said 45 river locations in multiple states were expected to reach major flood stage, with extensive flooding of structures, roads and other critical infrastructure possible.

In Christian County, which includes Hopkinsville, 6 to 10 inches (15.2 to 25.4 centimeters) fell since Wednesday evening, the National Weather Service said Friday afternoon. The rain caused the Little River to surge over its banks, and 4 to 8 inches (10.2 to 20.3) centimeters more could fall by Sunday, it said.

A pet boarding business was under water, forcing rescuers to move dozens of dogs to a local animal shelter, said Gilliam, the county executive. Crews rescued people from four or five vehicles and multiple homes, mostly by boat, said Randy Graham, the emergency management director in Christian County.

“This is the worst I’ve ever seen downtown,” Gilliam said.

Hundreds of Kentucky roads were impassable because of floodwaters, downed trees or mud and rock slides, and the number of closures were likely to increase with more rain late Friday and Saturday, Beshear said.

A landslide blocked a nearly 3-mile (4.8-kilometer) stretch of Mary Ingles Highway in the state's north, according to the Kentucky Transportation Cabinet. A landslide closed the same section of road in 2019, and it reopened last year, WLWT-TV reported.

Flash flooding is particularly worrisome in rural Kentucky where water can rush off the mountains into the hollows. Less than four years ago, dozens died in flooding in the eastern part of the state.

Extreme flooding across a corridor that includes Louisville, Kentucky, and Memphis — which have major cargo hubs — could also lead to shipping and supply chain delays, said Jonathan Porter, chief meteorologist at AccuWeather.

Swollen rivers and tributaries also swamped some parts in Ohio, and Gov. Mike DeWine said about 70 roads were closed. The southern half of the state was expected to see moderate flooding, which has not happened in four years, he added.

Forecasters attributed the violent weather to warm temperatures, an unstable atmosphere, strong wind shear and abundant moisture streaming from the Gulf. At least 318 tornado warnings have been issued by the National Weather Service since this week’s outbreak began Wednesday.

The outburst comes at a time when nearly half of National Weather Service forecast offices have 20% vacancy rates after Trump administration job cuts — twice that of just a decade ago.

At least two reports of observed tornadoes were noted Friday evening in Missouri and Arkansas, according to the National Weather Service.

“TAKE COVER NOW!” the weather service said on X in response to the one on the ground around the small Missouri town of Advance.

Earlier in the week, homes were ripped to their foundations in Selmer, which was hit by a tornado with winds estimated up to 160 mph (257 kph), according to the weather service. Advance warning of storms likely saved lives, as hundreds of people sheltered at a courthouse, the governor said.

In neighboring Arkansas, a tornado near Blytheville lofted debris at least 25,000 feet (7.6 kilometers) high, according to weather service meteorologist Chelly Amin. The state’s emergency management office reported damage in 22 counties from tornadoes, wind, hail and flash flooding.

Workers on bulldozers cleared rubble along the highway that crosses through Lake City, where a tornado with winds of 150 mph (241 kph) sheared roofs off homes, collapsed brick walls and tossed cars into trees.

Mississippi's governor said at least 60 homes were damaged. And in far western Kentucky, four people were injured while taking shelter in a vehicle under a church carport, according to the emergency management office in Ballard County.

Schreiner reported from Shelbyville, Kentucky. Associated Press writers Andrew DeMillo in Little Rock, Arkansas, Jonathan Mattise in Nashville, Tennessee, Adrian Sainz in Memphis, Tennessee, Jeff Martin in Marietta, Georgia, Obed Lamy in Hopkinsville, and John Raby in Charleston, West Virginia, contributed.