Hurricane Melissa’s 252-mph Gust Verified — Just 1 MPH Short of Global Record

Newly verified observations show Hurricane Melissa produced a wind gust of 252 miles per hour, just 1 mph below the fastest gust ever recorded on Earth and 4 mph stronger than any previously measured gust in a tropical cyclone at sea. The measurement comes from a dropsonde released by a Hurricane Hunter aircraft and was reviewed by National Oceanic and Atmospheric Administration and National Center for Atmospheric Research scientists.

How the reading was confirmed

The gust was captured by an NRD41 dropsonde, an instrument that transmits detailed profiles of wind, pressure and temperature from the top of the storm down toward the ocean surface. Atmospheric scientist Holger Vömel of the National Center for Atmospheric Research worked with NOAA meteorologists to examine the data and rule out instrument error. "Everything behaved exactly as it was intended to," Vömel said, after checking the dropsonde record for artifacts that can indicate a malfunction.

Gusts vs sustained winds

Scientists emphasize the important difference between short-lived gusts and sustained winds. The Saffir–Simpson hurricane scale is based on the highest one-minute sustained wind speed; gusts are transient bursts that can register much higher speeds but do not determine a storm's category. Melissa's sustained winds reached 185 mph, just 5 mph shy of the Atlantic record, and the storm tied for second place in Atlantic history for sustained wind speed.

Context and comparisons

The global gust record of 253 mph was measured during a 1996 tropical cyclone on Barrow Island, Australia, at a standard observation height of 10 meters (33 feet) above the ground. The Melissa dropsonde gust was recorded much higher above the ocean—roughly 20 times that height—so direct comparisons should account for measurement altitude and surface effects. Land features can channel and accelerate winds in ways that do not occur over open water, which influences how gusts are recorded onshore.

Melissa also reached a minimum central pressure of 892 millibars, tying it for the third-strongest hurricane on record in the Atlantic. On land, the storm was the strongest to make landfall in Jamaica and produced that nation's second-highest recorded rainfall total since 2000.

Human impact

Scientists say that while record-setting numbers draw attention to storm dynamics, the human consequences are the most important consideration. "This is a record-breaking sounding, and it's really amazing that we can observe that. But there's also people on the ground who suffered through that," Vömel said.

Editor's note: a paragraph was corrected after posting to clarify the height at which the 1996 Barrow Island gust was measured.