Weather Whys: Wind

A: There are several reasons why it’s windy one day and calm the next, says Brent McRoberts of Texas A&M University. Wind is caused by air flowing from an area of higher pressure to an area of lower pressure, he explains. “Add to that the rotation of the Earth, which also affects air flow,” he adds. “And during daylight hours, winds increase as sunlight heats the ground and causes convection to occur, meaning heat is moving away from the Earth’s surface. At night, this convection dwindles and the winds die down. Nature is always trying to balance things out, and the result of trying to balance and equalize pressure from one area to another results in wind.”

A: Winds that blow uphill are called upslope winds, and winds that blow downhill are called downslope winds, McRoberts adds. “Winds that blow from large bodies of water inland are called sea breezes. Santa Ana winds are dry winds that can fan forest fires, especially in California. The U.S. has some of the windiest weather on Earth. In fact, the highest wind speed ever recorded in the U.S. occurred April 12, 1934, on Mount Washington, N.H. For a few seconds, the wind blew an incredible 231 miles per hour.”