If you're getting together with others outdoors, a windy day might be best, researchers say.

The investigators found that when people socialize outside, the risk of coronavirus infection is as much as 45% greater when there's hardly any breeze than when there are stronger winds.

"The issue is really about an increased danger of infection spread in the presence of stale air as opposed to indoor versus outdoor settings," said study leader Sean Clouston. He is an associate professor in the public health program at Stony Brook University School of Medicine, in New York. "The findings imply we are all safer when air flow is more significant."

For the study, the researchers developed a statistical modeling program to analyze 96,000 COVID-19 cases in Suffolk County, N.Y., between March 16 and Dec. 31 of 2020. These numbers were combined with National Oceanic and Atmospheric Administration daily data on wind speeds and temperatures.

Clouston and his team found that on days with temperatures between 61 and 82 degrees Fahrenheit, coronavirus transmission was significantly higher when the average wind speed was under 5 miles per hour than when there was a bigger breeze.

The findings were published online recently in the journal BMC Infectious Diseases.