Barometer - An instrument used to monitor variations in air pressure at the surface. The first barometer was invented by the Italian physicist Torricelli in 1643. For the centuries to follow, the barometer was the main tool used in weather forecasting.

isodrosotherm - A line of equal dew point temperature. Isodrosotherms are typically drawn for surface dew points. They can give meteorologists a good read on where surface fronts are located since tightly packed isodrosotherms indicate a dew point gradient.

Centripetal Force - A force that acts on an object moving in a curved path. Centripetal force is directed towards the center of an objects axis of rotation. This force is responsible for keeping an object moving in a curved path.

Microburst - A strong and localized downdraft that occurs beneath a strong to severe thunderstorm. Microburst's occur on a small scale, as most are smaller than a mile wide in diameter. These localized, intense winds can produce major damage and typically last for a matter of seconds to several minutes.

Rainbow - An arc of concentric colored bands formed by refraction that occurs when sunlight passes through raindrops. Anytime you see it raining while the sun is out, there will almost always be a rainbow. Just position yourself with your back to where the sun is shining and you will find it.

Updraft - A stream of air that accelerates upward from the surface. The strongest updrafts are found within thunderstorms. Strong thunderstorms can see updraft speeds of over 100 mph!

Stratopause - The boundary or transition layer between the stratosphere and mesosphere. The stratopause is located around 30 miles above the surface of the earth.