People planning to picnic at Ala Moana Beach Park Monday will be allowed to stake out their favorite spot the day before and stay overnight — within strict rules — the Honolulu Police Department and city Department of Parks and Recreation said Friday.

The park opens at 9 a.m. Sunday, and people will be allowed to set up in the picnic and canopy areas. But all cars must be out of the park by 10 p.m. Sunday. No more than two people will be allowed to stay overnight at a picnic site after the park closes for the day. The park will reopen at 4 a.m. Monday.

Curbside parking outside the park along Ala Moana Boulevard will not be allowed Sunday night.

The Police Department predicts about 40,000 people or more will be present at the park for the Fourth of July.

"No alcohol, no shopping carts, no tents, everything on the park rules and regulation signs all over the park (apply)," Rosalind Young, a parks district manager, said at a news conference Friday.

Canopies with one flap will be allowed, Young said.

No animals or fireworks will be allowed, police Sgt. Deric Valoroso said.

"We ask that people not line up on Ala Moana Boulevard (when the park opens)," Valoroso said. Police also said people are not allowed to reserve parking stalls with coolers, cones or any items.