Time to leave your pants at home. Across the globe, thousands of commuters are expected to ride their local subway trains Sunday in their underwear in honor of the annual No Pants Subway Ride celebration.

The parade of bare thighs will take place in Mexico City, Sydney, Paris and other cities. In Chicago, nearly 200 participants are expected to brave low temperatures of 19 degrees for a pants-free subway ride. In London, the celebration is called No Trousers On The Tube Day and often features unusual underpants. Travelers plan to board the train at different stops to further confuse the unaware.

In Boston, the 2015 No Pants Subway Ride festivities will be held from 2-6 p.m EST, the Boston Globe reported. The city is celebrating its eighth year of train riding without pants, and temperatures are expected to hover around 28 degrees. In New York, participants will ride from 3-5 p.m. EST in Queens, Brooklyn and Manhattan.

"It's to cause a little bit of a scene but not to offend," Justin Hardesty, 35, who has been participating in the Chicago no-pants ride for eight years and has organized the event for six years, told the Redeye edition of the Chicago Tribune. "Everyone has underwear. Everyone is legally appropriately dressed. We're not out to offend. We're out to give people something to talk about."

Costumes are not encouraged. Organizers tell participants to wear proper attire. Thongs are discouraged. Hardesty said he typically wears two pairs of underwear. "I don't know if I want just one layer of fabric between me and the CTA [Chicago Transit Authority] seat," Hardesty said.

The event has drawn some criticism from public officials in recent years. In Romania, subway officials said Friday those "who disturb public order or are indecent will be fined" and reported to the police, the Associated Press reported.

No Pants Subway Ride began in 2002 in New York as a public prank and has since been celebrated by commuters around the world. Organizers call it "an international celebration of silliness."