Here are a list of road closures:
- San Vicente Boulevard will be shut down between Santa Monica Boulevard and Melrose Avenue.
- Santa Monica Boulevard will be closed between Doheny Drive and Croft Avenue/Holloway Drive.
- La Cienega Boulevard will be closed to north and southbound traffic at 4 p.m. Monday.
- Some smaller streets will also be closed, including Robertson Boulevard, Almont Drive and La Peer Drive.
For a full list of closures, visit http://www.weho.org/visitors/events-in-the-city/halloween-carnaval/street-closures.
All roads are expected to reopen by 7 a.m. Tuesday.
PHOTOS: West Hollywood Halloween Carnaval 2014
As many as half a million people are expected for the annual Halloween bash, billed as the biggest Halloween party in the world.
This year's theme is disco, and actor-singer Darren Criss, best known for his role in "Glee," will serve as "Carnaval King."
According to the city's website, revelers will not be allowed to have backpacks, camera bags or totes - you can carry items in clear plastic bags. Also, you will not be allowed to bring anything that resembles a weapon.
Although there were no specific threats for Monday night's event, considering what happened in Orlando, what's happened abroad, the scare at the Pride event, law enforcement and the city are taking every precaution when it comes to security.
The Los Angeles County Sheriff's Department says its West Hollywood station has added more personnel to the already well-patrolled event.
The city will suspend permit parking restrictions from 11 a.m. Monday until noon Tuesday, but city officials warned residents to ensure they are parking in West Hollywood, since neighboring Los Angeles and Beverly Hills will continue to enforce all parking restrictions.
Public parking lots will be available, and a list of locations and prices is also available here: http://www.weho.org/visitors/events-in-the-city/halloween-carnaval/parking-information.
City officials encouraged residents to carpool or use public transit.
City News Service contributed to this report.