Category: Define

Greenwich Mean Time (GMT) The name of the twenty-four hour time scale which is used throughout the scientific and military communities. Standard Time begins at

Ground Clutter A pattern of radar echoes reflecting off fixed ground targets such as buildings or hills near the radar. This may hide or confuse

Gulf Stream The warm, well-defined, swift, relatively narrow ocean current which exists off the east coast of the United States, beginning near Cape Hatteras. The

Gully Washer A heavy rain shower that occurs suddenly, possibly creating a flash flood. Shower Precipitation from a convective cloud that is characterized by its

Gust A sudden significant increase in or rapid fluctuations of wind speed. Peak wind must reach at least 16 knots (18 miles per hour) and

Gust Front The leading edge of the cool, gusty surface winds produced by thunderstorm downdrafts. Sometimes confused with an outflow boundary. Gust A sudden significant

Gustnado A weak, and usually short-lived, tornado that forms along the gust front of a thunderstorm, appearing as a temporary dust whirl or debris cloud.

Heat A form of energy transferred between two systems by virtue of a difference in temperature. The first law of thermodynamics demonstrated that the heat

Heat Balance The equilibrium which exists on the average between the radiation received by the earth and atmosphere from the sun and that emitted by

Heat Index The combination of air temperature and humidity that gives a description of how the temperature feels. This is not the actual air temperature.