Earth . Space . Weather . The Edge . Newsletter . News to go
Asteroids . Comets & Meteors . Drought & Fire . Earthquakes . El Niño . Environment . Global Warming . Health
Hubble . Hurricanes . Mars . Moon . Science research . Space missions . Solar System . Technology . Tornadoes . Volcanoes

101 . Q&A . A B C D E F G H I J K L M N O P Q R S T U V W X Y Z . Site map . Search

ezscienceindex

Telescope basics buying tips **includes animations

Temperature

Thermal: Small rising columns of air caused by surface heating.

Thunder: The sound caused by a lightning stroke as it heats the air and causes it to rapidly expand. Animated lighting page explains which comes first and why.

Tides **includes animations

Tonight's sky *includes images

Tornadoes **includes animations

Trade winds: Persistent tropical winds that blow from the subtropical high pressure centers towards the equatorial low.

Tropical cyclone: A warm-core, nonfrontal low pressure system that develops over tropical or subtropical waters and has a definite organized surface circulation.

Tropical depression: A tropical cyclone in which the maximum one-minute sustained surface wind speed is 38 mph or less.

Tropical disturbance: An organized mass of tropical thunderstorms, with a slight cyclonic circulation, and winds less than 20 knots.

Tropical storm: A tropical cyclone in which the maximum one-minute sustained surface wind speed of 39 mph to 73 mph.

Tropical storm warning: A warning for tropical storm conditions including sustained winds within the range of 39 to 73 mph that are expected within 24 hours.

Tropical storm watch: An announcement that a tropical storm poses or tropical storm conditions pose a threat to coastal areas, generally within 36 hours. A tropical storm watch should normally not be issued if the system is forecast to attain hurricane strength.

Troposphere

Trough: An elongated area of low pressure at the surface or aloft.

Tule fog: Radiation fog in the central valley of California that forms during night and morning hours in late fall and winter months following the first significant rainfall. A leading cause of weather related casualties in California.

Turbulence: Disrupted flow in the atmosphere that produces gusts and eddies.

Typhoon: A warm-core tropical cyclone with one-minute sustained winds of 74 mph or more that forms in the Northern Hemisphere west of the International Dateline (the Western Pacific). The term hurricane is used for Northern Hemisphere cyclones east of the International Dateline to the Greenwich Meridian.

Tsunamis **includes animations