FLIR RAYMARINE A75 WiFi - Page 381

Term Denition
Occluded Front An area where warm air is pushed upwards as a cold front overtakes a warm front and pushes underneath it.
Precipitation
Moisture that is released from the atmosphere as rain, drizzle, hail, sleet or snow, as well as dew and fog.
Pressure Centre A region of high or low pressure.
Squall line A non-frontal band, or line, of thunderstorms.
Super typhoon A typhoon that reaches maximum sustained 1 minute surface winds of at least 65 m/s (130 kt, 150 mph).
This is the equivalent of a strong category 4 or 5 hurricane in the Atlantic basin or a category 5 severe
tropical cyclone in the Australian basin.
Tornado
A funnel shaped whirlwind which extends to the ground from storm clouds.
Tropical cyclone
A low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms
and, in the Northern Hemisphere, a counterclockwise circulation of winds near the earth's surface.
Tropical
depression
An organized system of clouds and thunderstorms with a dened surface circulation and maximum sustained
winds of 38 mph (33 kt) or less.
Tropical storm
An organized system of strong thunderstorms with a dened surface circulation and maximum sustained
winds of 3973 mph (34 63 kt).
Tropics
An area on the Earth's surface that lies between 30º north and 30º south of the equator.
Trough
An elongated area of relatively low atmospheric pressure, usually extending from the centre of a low
pressure region.
Typhoon
The name for a tropical storm originating in the Pacic Ocean, usually the China Sea. They are basically the
same as the hurricanes of the Atlantic Ocean and the cyclones of the Bay of Bengal.
Wave cyclone
A storm or low pressure centre that moves along a front.
Wave period
The period is the time gap between successive waves and the longer the period the faster the waves travel.
Weather application (North America only)
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