Air turbulence from a storm can occur sooner than you expect

Jagged nerves and spilled drinks are the most common consequences of a bumpy flight, but strong air turbulence can also cause physical harm. And while thunderstorms are a known cause of air turbulence, little is known at what distance from a storm shaky conditions are likely to persist.

To answer this question, researchers recently analyzed millions of air turbulence measurements collected from commercial aircraft. The team found that there was an increased risk of disruptive flight more than 55 miles away from a thunderstorm, which is about three times the current recommended storm avoidance distance from the Federal Aviation Administration. These findings, published this month in the Bulletin of the American Meteorological Society, could underlie new guidelines for storm avoidance, the researchers suggest.

Pilots and emergency services on the ground have been keeping an eye on the weather for a long time. “The connections between meteorology and aviation go back a long way,” said Stacey Hitchcock, an atmospheric scientist at the University of Oklahoma in Norman.

Thunderstorms are particularly worrying for pilots. “Over short distances there are really rapid changes in vertical and horizontal movement,” said Dr. Hitchcock. These chaotic movements — which can also be caused by jet stream winds and air movement around obstacles like mountains — can cause planes to fly up and down, creating a turbulent feeling that many aviators are all too familiar with.

In the past, daredevil pilots played a key role in elucidating how aircraft experience turbulence near thunderstorms: A fleet of five P-61C Black Widow aircraft repeatedly flew through thunderstorms over Florida and Ohio in the 1940s. “No storm could be avoided because it seemed too big or too severe,” a lead analyst for that effort, the Thunderstorm Project, said later at a meeting of the National Weather Association.

Today, however, scientists have access to a wealth of data about air turbulence. “Almost all commercial aircraft now collect some form of turbulence data,” said Todd Lane, an atmospheric scientist at the University of Melbourne in Australia who was involved in the new research.