People are more likely to try those three party drugs and marijuana during the summer, researchers found, with over a third of LSD use and around 30% of ecstasy and marijuana use starting in the season. Around 28% of cocaine use also began in the summer.

The findings, published Tuesday in the Journal of General Internal Medicine, suggest a slight but consistent increase in people’s willingness to try drugs as the weather warms and young people take a break from school.

Dr. Joseph Palamar, the study’s lead author and an associate professor of population health at the NYU School of Medicine, said that summer brings idle time, especially for young people with little to do. “People aren’t working like crazy,” he said, and “if you’re going out, maybe just because of the warmer weather, you might be hanging out with people more.”