Straight-line winds are responsible for most thunderstorm wind damage and should not be underestimated. Winds can exceed 100 miles per hour (mph). Straight-line wind damage is often mistaken for tornado damage. One type of straight-line wind is known as a microburst.
A microburst is a small area of rapidly descending air. They can and do cause damage equal to that of a strong tornado. They are also an extreme aviation hazard.
Most flash flood fatalities occur at night and the majority of victims are trapped in automobiles.
Strong currents of air within a storm carry water droplets high enough to freeze, and then begin to fall until they are lifted again. This cycle continues until the particles become too large and heavy for the updraft to lift, and they fall to the ground. Large hail stones can fall at speeds greater than 100 mph.