Saturday
Westy Fest — Fall festival with carnival games, trick-or-treating, hot air balloon glow, live musical, food trucks, jumping castles and more, noon-8 p.m., Westminster City Park, 10455 N. Sheridan Blvd., Westminster; westminsterco.gov/specialevents.
Jamtoberfest — With live music, special beers on tap, food trucks and more, 1-8 p.m., Oskar Blues Brewery & Taproom, 1640 S. Sunset St., Longmont; oskarblues.com/location/longmont.
Pumpkin Plunge — Jump in pool, pick two pumpkins and decorate, includes open swim and goodie bag, 3-6 p.m., Buck Recreation Center, 2004 W. Powers Ave., Littleton, $25-$27. For ages 3-12, children ages 3-5 must be accompanied by adult in water. Registration: tinyurl.com/mrx54wv7.
Safe Street Halloween — Hosted by Northglenn Police Department with trick-or-treat fun, inflatables, music and more, 4-7 p.m., Centennial Park, north of the Northglenn Marketplace, 104th Avenue and Interstate 25, Northglenn; northglenn.org/ssh.
Catrina Ball 2024: Fiesta de Almas — 4:30-8:30 p.m., Firehouse Art Center, 667 4th Ave., Longmont. Registration: tinyurl.com/mr2cw5m8.