Why do hot air balloons only fly at sunrise or a few hours before sunset?
During the summer, the winds are the calmest in the morning or early evening. In our part of the country, balloons usually will not fly in winds more then 10-12 miles per hour. The hills and valleys create turbulence when it is windy, which makes it unsafe to fly. In the plain states where it is flat, balloons are able to fly in higher winds because the land is flat and therefore usually less turbulent. The heat of the sun also causes turbulence as it warms the ground. In the winter, it is possible for balloons to fly anytime during the day, if winds are not related to weather fronts.
