Aleutian Low - a persistent low pressure center located near the Aleutian Islands on the mean charts of sea level pressure from late fall to late spring. It represents one of the main centers of action for atmospheric circulations in the northern hemisphere. Some of the strongest lows of the season are oftentimes Aleutian lows.

Computer Model - A system of computers which run complex physics equations on meteorological data to produce mathematical forecasts. Forecast models are first initialized with the current conditions in the atmosphere, and then thru a series of complex algorithms, they model what will be happening anywhere from 12 to 180 hours from the current time. There are several computer models that meteorologists utilize in predicting the weather.

Pluie - This is the french word for rain. To say, "it is raining today" one would say, "Il pleut aujourd'hui."

Super-Typhoon - A tropical cyclone in the western Pacific basin that has one minute sustained wind speeds of a last 150 mph. This corresponds to what would be a category 4 or greater hurricane if the tropical cyclone were in the Atlantic or eastern Pacific.

Doldrums - An east-west belt of light and variable surface winds where the trade winds of the two hemispheres converge. This region is located in a belt just north and south of the equator. Sailers dubbed this area as the doldrums because the lack of wind would mean their ships would stay idle for weeks at a time.

Sub-vortices - Small areas of intense rotation located within a type of tornado called a multi-vortex tornado. These spinning whirls can be thought of as individual tornadoes that are mixed within the main tornado. These are also sometimes referred to as suction vortices and the winds within them can be 100 mph stronger than the main body of the tornado. These can explain why the damage path in a tornado can vary greatly.

Anvil - The flat, spreading top of a cumulonimbus cloud, often shaped like an anvil. Anvils are a result of strong winds near the top of the thunderstorm. Thunderstorm anvils may spread hundreds of miles downwind from the thunderstorm itself, and sometimes may spread upwind.