Thirty years ago today, a violent blast of cold air crashed down from a thunderstorm’s clouds above Andrews Air Force Base. As the so-called microburst slammed into the ground and fanned out in all directions, the wind speed was clocked at 149 mph (at the time, the highest-ever measured wind speed by an anemometer).

Diagram of a microburst (NOAA)

Just six minutes before this wind gust was measured, Air Force One had landed at Andrews, with President Ronald Reagan aboard. His timing was extraordinarily fortunate.

“The pilot was aware of storms in the area, but apparently no warning had been issued of possible wind shear – sudden reversals of wind direction,” describes a 1984 account from the New York Times. “The plane landed on a dry runway and was parked before the microburst struck.”

Microbursts have been linked to numerous aviation accidents. Their winds are often comparable to or even more powerful than those in tornadoes, reaching speeds of 80-100 mph or higher. They’re especially hazardous for aircraft during take-off and landing, as they involve sudden changes in wind speed and/or direction.

Although they were discovered by University of Chicago scientist Ted Fujita in the 1970s, the concept of microbursts remained controversial into the early 1980s.

“In 1983, the consensus in both aviation and meteorology was that Dr. Ted Fujita’s theory that microbursts existed and were a mortal hazard to aircraft was wrong,” writes Mike Smith, author of “Warnings: The True Story of How Science Tamed the Weather”. “It would be another two years and one day, August 2, 1985, when Delta 191 crashed in Dallas before Dr. Fujita’s theory would be accepted.”

The Delta crash of 1985, which killed 137 people, motivated microburst detection and pilot training initiatives through the Federal Aviation Administration.

“Pilots now train regularly to survive it,” reports a piece from the NY Times in 2005. “Millions of dollars have been spent on sophisticated Doppler radar and sensors to detect it. It is almost certain that thousands of passengers are alive today who never knew – or ever will know – of their potential danger.”

Today, the University Center for Atmospheric Research’s Aviation Application Program continues to develop systems to better to detect these dangerous storms.

Related: Microburst! Inside the explosive storm that blasted D.C., Md. (Photos/video)