Heading for Ocean City over the Chesapeake Bay Bridge during the worst of the Memorial Day weekend rush — between 2 and 4 p.m. Friday — will add about three hours to the trip, travel data company Inrix says. (Michael Lutzky/The Washington Post)

Here’s news that 810,950 of you can use: The best time to get out of town this Memorial Day weekend is before 9 a.m. Friday.

The first number is AAA’s survey-based projection of how many people will set out somewhere by car this weekend; the second one comes from the travel data company Inrix, which ran the numbers of past holiday weekend getaways to find the optimal hour for escaping the Washington region.

With about 15 percent of the region’s population heading out, those who remain might expect a quiet weekend in their absence, but the outbounders will be replaced by a number of tourists equal to or greater than those who are gone.

“Almost a million people leaving, almost a million coming in,” said John B. Townsend II of AAA. “We are seeing the most robust number of travelers since 2005.”

Townsend said the slight increase in planned travel from Washington this year came in the absence of sequestration or the threatened federal shutdown that made people leery of travel a year ago.

“That cast a pall over the travel forecast,” he said. “In the Washington metro area, they now are foot loose and fancy free.”

AAA announced its annual survey results Tuesday on Kent Island, with the Chesapeake Bay Bridge looming as a backdrop for the television cameras. About 333,000 cars will cross the bridge this weekend as people head to the Eastern Shore and beaches in Maryland, Delaware and Virginia.

Heading for Ocean City during the worst of the rush — between 2 and 4 p.m. Friday — will add about three hours to the trip, Inrix said.

“I think after this harsh winter everybody’s going to want to break out, and that’s a good sign for Ocean City,” said Ocean City Mayor Rick Meehan. “It’s never felt better to be out on the sand.”

Inrix said people who head south toward Richmond from 2 to 4 p.m. Friday will see their travel time double. The worst of it for those headed out Interstate 270 or north toward Baltimore will come after 4 p.m. as commuters enter the mix.

Michelle Holland of the Virginia Department of Transportation said the Interstate 95 work zones that stretch from the Capital Beltway to Stafford would be quiet through the weekend. But but for the rest of the summer, drivers can expect slow going.

“After Memorial Day weekend they need to be prepared for construction delays,” she said.

Overall, AAA says 907,750 people plan to leave the region for the weekend. About 67,000 of them will fly, while others will go by bus, rail or boat.

They will be among 36 million people nationwide who plan to travel 50 miles or more from home this weekend, AAA said.

It’s estimated that 382 of them will die in traffic crashes and 40,900 who survive crashes will end up in emergency rooms, according to the National Safety Council.

“Sadly, we know this long holiday weekend will end with too many preventable deaths and injuries,” said Deborah Hersman, president of the National Safety Council and former chairman of the National Transportation Safety Board. “We issue these estimates to draw attention to risks on the roadways and encourage drivers to take extra precautions so needless tragedies can be prevented.”

The Transportation Security Administration says it expects 2.6 million airline passengers to pass through its airport security checkpoints this weekend.

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