Kossin wanted to see if, on average, the traveling speed of such tropical cyclones was slowing down. To find out, he used data from the U.S. National Hurricane Center and the Joint Typhoon Warning Center to study the position of such storms’ centers every six hours. From those, he was able to calculate the moving speed of these coastal storms between 1949 and 2016.

Source: Los Angeles Times June 06, 2018 16:52 UTC