Thunderstorms are formed by the combination of three main ingredients: moisture, unstable atmospheric air and an external acting force making the damp and volatile air rise upward. Thunderstorms come in several different... More »

Meteorologists use the Lifted Index (LI) to estimate the atmosphere's potential to produce severe thunderstorms. The Lifted Index measures the temperature of rising air in the atmosphere to determine the likelihood of a ... More »

Obvious clues to look for that a thunderstorm is on the way include a static noise on an AM radio station, the smell of rain and a sudden drop in temperature along with a strong breeze. Other signs are a change in wind d... More »

Tornadoes form when unstable air in a thunderstorm creates a horizontal rotation in the clouds and strong downdrafts draw that vortex down to the ground. Overlapping fronts can trigger the wind shear necessary to initiat... More »

Tornadoes are narrow, circulating columns of air that originate from a supercell thunderstorm, from the cloud to the ground, and constantly become darker as they pick up dirt and debris from the ground. Tornadoes move at... More »

The natural forces that form a tornado involve a rotating column of air that extends from the base of a thunderstorm cloud to the surface of the ground. These rotating forces tend to be violent due to their intense speed... More » Science Weather & Tides Storms

According to the National Oceanographic and Atmospheric Administration, tornadoes form when warm air creates a rotating updraft in a powerful thunderstorm. When winds blow in sharply different directions or at different ... More »