Mayor Bloomberg has warned revelers to leave their alcoholic beverages at home and to wear waterproof clothing in case of rain on Saturday night when they head to Times Square to watch the 1,070-pound New Year’s Eve ball drop.

At a press conference in Times Square early yesterday, Mr. Bloomberg outlined some of the security procedures that will be in place for the 100th annual dropping of the New Year’s Eve ball.

The streets surrounding the New Year’s event on Broadway and Seventh Avenue between 42nd and 47th streets will be closed to traffic starting at 3:30 p.m. New Yorkers and tourists entering Times Square will be subject to bag searches – during which police will look for alcohol and potentially dangerous items.

It was alcohol that drew the mayor’s strongest pre-New Year’s warning: “Celebrate safely,” he said. “Don’t drink and drive or get in a car with someone who does.”

The Police Department will conduct drunk-driving enforcement with DWI patrols at checkpoints throughout the city. The city has increased drunk driving arrests by 86% over the last four years, and it has seized 1,696 vehicles from drunk drivers thus far in 2005. According to police, the new efforts have helped reduce drunk driving fatalities by 4% this year.

Mr. Bloomberg recommended that, if possible, revelers should leave their bags and backpacks at home.

He also recommended that celebrators wear “waterproof clothing” in case the predicted rain showers arrive during the celebration, and suggested comfortable shoes, as visitors will not be able to park their cars at Times Square and the closest subway stops will be shut down.

Starting at 12 a.m. on Saturday, no parking will be allowed on cross-town streets from 34th Street to 57th Street between Sixth and Eighth avenues. Parking will also be prohibited on the west side of Sixth Avenue between 34th and 59th streets, the east side of Eighth Avenue between 34th and 57th streets, and on 48th street between Fifth and Ninth avenues.

At 4 p.m. Friday, no traffic will be allowed on Seventh Avenue or Broadway between 42nd and 59th streets. Sixth and Eighth avenues also will be blocked between 43rd and 47th streets.

Additional streets will be closed down at 6:30 p.m. on Saturday.

“People are strongly advised to use public transportation,” the Police Department release warned yesterday.

The festivities at Times Square will begin at 6 p.m., when the New Year’s Eve Ball is raised to the top of 1 Times Square. At 6:30 p.m., Times Square Alliance sanitation crews will distribute pom-poms and confetti as well as hats and ear warmers.

At midnight, the ball, which is illuminated with 432 light bulbs, will drop.

About 13 hours later, Mr. Bloomberg will be officially sworn in for his second term at City Hall.

Yesterday, he said his inaugural address would be a perfect opportunity to thank New Yorkers for his first four years.

“I really think New York City is poised to continue its progress,” he said. “We’ve learned a lot about each other. I’ve learned a lot over the last four years. We’ve put in place some of the building blocks that we can take this city forward on. And that’s the place to talk about those.”

Mr. Bloomberg said New Yorkers should stay tuned for his State of the City address to hear any “specifics on individual programs.”

The Associated Press reported yesterday that workers from city agencies that joined in the Hurricane Katrina relief efforts, along with New Orleans jazz trumpeter Wynton Marsalis, will serve as the guests of honor at the annual New Year’s Eve bash in Times Square.