Airplane Turbulence Can Start Earlier Than You Expect

This is your captain speaking: When thunderstorms are in the forecast, you may need to buckle those seatbelts a lot sooner than you’re used to.

Rattled nerves and spilled drinks are the most common outcomes of a choppy flight, but intense air turbulence can also cause bodily harm. And while one well-known cause of air turbulence is thunderstorms, it’s poorly understood how far from a tempest shaky conditions are likely to persist.

To answer that question, researchers recently analyzed millions of measurements of air turbulence collected by commercial aircraft. The team found that a heightened risk of a jarring flight extended more than 55 miles away from a thunderstorm, which is roughly three times the storm-avoidance distance currently recommended by the Federal Aviation Administration. These findings, published this month in The Bulletin of the American Meteorological Society, could inform new guidelines for storm avoidance, the researchers suggest.

Pilots and dispatch crews on the ground have long kept an eye trained on the weather. “The links between meteorology and aviation go way, way back,” said Stacey Hitchcock, an atmospheric scientist at the University of Oklahoma in Norman.

Thunderstorms are of particular concern to pilots. “You get really rapid changes in vertical and horizontal motion over short distances,” Dr. Hitchcock said. Those chaotic motions — which can also be caused by jet stream winds and air moving around obstacles like mountains — can cause aircraft to go up and down, creating the tumultuous sensation that’s all too familiar to many fliers.

In the past, daredevil pilots played a key role in revealing how aircraft experience turbulence near thunderstorms: A fleet of five P-61C Black Widow aircraft repeatedly flew through thunderstorms above Florida and Ohio in the 1940s. “No storm was to be avoided because it appeared too large or too violent,” a senior analyst for that endeavor, the Thunderstorm Project, later said at a meeting of the National Weather Association.

Today, however, scientists have access to troves of air turbulence data. “Almost all commercial aircraft now are collecting 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.