Had Annette Funicello and Frankie Avalon been on the scene, there might have been a movie: "Beach Party Jam" -- traffic jam, that is.

But Annette and her beach movie costar, Frankie, hot stuff for the teen-aged set 25 years ago, seemed to be the only ones missing today from The Great Labor Day Weekend Beach Exodus Jam.

Proportions of the jam, and smaller "jamettes" along the way, were epic -- especially for the hot, sweaty cast of thousands whose cars and vans hugged the tarmac much longer than the usual three hours it takes to travel between Washington and the Maryland-Delaware beach havens. Just reaching the Chesapeake Bay Bridge from Ocean City, Md., today took four hours.

This weekend, it was estimated that more than 250,000 visitors poured into Ocean City's high-rises and apartment houses, said Susan Seifried, spokeswoman for the city's tourism department.

But they had to leave. Traffic earlier this afternoon glided smoothly out of Ocean City, far into the the lush rolling farmland of Worchester and Talbot counties.

The first jammette, a sneak preview of the snail-slow main feature ahead, came at Cambridge, site of a chicken packing company, several other industries and a bridge that crosses the Choptank River. Traffic approaching the bridge ground to a crawl.

"At that one place with a bridge, it got pretty nasty," Chris Troxel, a 21-year-old from Baltimore, said later just outside Easton, where he was resting by the roadside. Between long gulps of a soft drink, Troxel said he and his three friends were cooling themselves and his car, a 1974 burgundy Camaro that had overheated in the jam.

The four, partying and joking about the traffic from their roadside resting place, said they had planned to leave Ocean City and their room at The Tides motel before traffic got heavy this afternoon. Instead, they pushed off at 3:30 -- timing guaranteed to hit the crescendo of The Jam.

"My car got stolen when we were [in Ocean City] and I just got it back before we left, or we would've left this morning," Troxel said, surveying the tie-up.

It began at the intersection of routes 404 and 50, 17 miles south of the bay bridge, around 2 p.m. when the Kent Narrows Bridge was raised on its hourly holiday schedule, said Kim Tolan, 28, part-time manager of T's Produce. Her's is the last of a string of summer fruit and vegetable stands along Rte. 50 before the bridge.

"We had a lot of business when the traffic wasn't bad -- up until about 2. We sold all the corn. When it gets backed up like this, people don't get out of line to stop for produce; they're too desperate to keep their spaces," Tolan said.

Tolan, who lives in Easton, added that at this time of year, "locals just stay off this road." Gazing out at miles of cars that looked like they were parked single-file in two pin-neat rows, Tolan said, "It's never been this bad."

As some drivers split off Rte. 50 toward Delaware and points north, others coming back from weekend jaunts in Easton, St. Michael's and Oxford, Md., added to the wide river of traffic.

Three T-shirted, teen-aged youths, cans of beer in hand, walked along the roadside, yelling, "Hey, baby, you're a fox," at pretty, sunburned women in cars. In response to the bravado, windows were quickly rolled up.

Around 7:30 p.m., an awesome storm raged across the bay, sending some travelers scurrying for cover and dinner at Hemingway's, a seafood restaurant in Stevensville within sight of the bay bridge.

The manager on duty, Wanda Steele, said escapees from the travel jam had been coming in steadily all day.

But the restaurant did not become packed until the storm hit. The vertical lightning over the bay was spectacular.

And out on Rte. 50, the traffic continued to creep along.

As singer/songwriter James Taylor might have put it, "Damn this traffic jam/How I hate to be late/ Hurts my engine to go so slow/ Damn this traffic jam."