LOS ANGELES -- Thousands of doctors and nurses will bunk at hospitals, an emergency operation center will be set up and Southern California residents are being urged to stay home and stock up on food.
One major airline offered $4 seats to help people avoid the looming mess, selling out of tickets in three hours.
A 10-mile stretch of Interstate 405 -- a vital artery that links population centers north and south of the Santa Monica Mountains -- is shutting down for 53 hours this weekend. The closure, a necessary part of a major highway reconstruction project, is being dubbed "Carmageddon," evoking images of gridlock, road rage and other traffic nightmares that it might spawn in car-dependent Southern California.
Celebrities are among those sounding the alarm, via Twitter messages urging residents to stay off the road starting at midnight Friday.
"This weekend, LA! Avoid Carmageddon, Gas-zilla, 405-enstein, Grid-lock-apalooza! STAY HOME. Eat & shop local," Tom Hanks tweeted this week.
Beyond tongue-in-cheek apocalyptic warnings, city leaders stressed that real public safety concerns exist: Helipads have been cleared for air ambulances and 200 extra firefighters and paramedics will be on duty, some of them positioned along the shuttered freeway to protect fire-prone hillsides in the area. Four big hospitals near the freeway on the city's west side are setting up cots and putting thousands of doctors, nurses and medical personnel in hotels and dorm rooms so they don't show up late to their shifts.
The UCLA Health System placed advanced orders for medical supplies and food, even preparing 5,200 box lunches for staff, ahead of the shutdown. It has three helicopter companies on standby to transport patients and human organs in the event of emergency operations.
"You can't take a chance when you deal with patient safety and patient care," said Dr. Wally Ghurabi, the emergency director of Santa Monica-UCLA Medical Center. He planned to sleep in the E.R. throughout the weekend instead of commuting the 20 miles from his home in Torrance to the hospital.
Authorities are hammering the same message to drivers. Starting last month, they flashed freeway electronic signs warning drivers to "EXPECT BIG DELAYS."
"The best thing is to stay home if you can, don't drive if you don't have to," said Michael Miles, a California Department of Transportation official. "Be prepared, treat it like it's a disaster."
On a typical July weekend, about a half-million vehicles use the section of the freeway, known locally as the 405, to get to major destinations such as the airport, beaches and interchanges to other major highways. Transportation officials said a full shutdown is necessary to replace the 50-year-old Mulholland Bridge as part of a $1 billion project to widen the perpetually bottlenecked segment through the Sepulveda Pass.
Authorities said a full closure was necessary to demolish one side the span, and they picked this weekend to minimize impact to traffic on a workday. They expect another closure next year to replace the other half.
To discourage driving, transit officials will offer free rides on the subway and certain bus lines and add more train service.
Anticipating potential backups caused by drivers who won't heed the warnings, the city plans to deploy traffic engineers to monitor the ripple effect on roads and to manage key intersections. Mayor Antonio Villaraigosa is urging residents to stay close to home and shop locally if they must go out.
"We need every Angeleno to chip in and turn this Carmageddon into a unique opportunity," he said Wednesday.
Villaraigosa's not the only one seizing the opportunity to drum up business this weekend.
A helicopter company is advertising $150 rides to zip people to downtown and Los Angeles International Airport. JetBlue is providing $4 to $5, 30-minute "Over the 405" flights between Long Beach Airport and Bob Hope Airport in Burbank, calling the service a "planepool" between the San Fernando Valley and the beach.
Hotels and restaurants are offering discounts, movie theaters along the freeway are giving away popcorn. A fitness instructor suggests "Carmageddon yoga" for stressed-out drivers. And Dr. Arnold Klein, Michael Jackson's longtime dermatologist, is giving 25 percent off on Botox injections.
"Instead of being stuck on the freeway and not being able to do anything you could be in my office and be more beautiful," Klein said.
Waze, a company that provides GPS navigation applications for smartphones, set up a website and plastered posters across the city to urge drivers to sign up for its service and survive "this imminent disaster."
Dire warnings have shown to work during the 1984 summer Olympics and a 1987 visit by Pope John Paul II. The city braced for the worst, but traffic flowed freely because people avoided driving.
Some people are making the best of the circumstance by organizing mass bicycle rides and neighborhood parties.
The pastor of a church on Mulholland Drive moved his Sunday service to a theater so his roughly 3,000 congregants can worship.
Mark Wadsworth of Bel Air Presbyterian Church said he doesn't expect everyone to attend. He compared the circumstance to Colorado, where he previously preached, when fewer people showed on snowy days.
"This is the L.A. version of a snow Sunday," he said.
Meanwhile Moshe Shmuel, who's expecting 120 guests at his Saturday wedding, said he was worried that some people flying in from Israel and South Africa may have trouble getting from the airport to the ceremony at a private estate in Bel Air. He told his guests to leave extra early so they can show up on time.
"Lucky for us, the rabbi lives close-by. He doesn't need to take the freeway," Schmuel said.