Weather Terminology from WXYZ
Have you ever wondered what humidity actually is? Confused about the dew point?
You can learn all about these and other weather terms from
WXYZ's Weather Terms below.
Be sure to also use our
interactive WXYZ Weather Calculators to see how temperatures can be affected by humidity, dew point, and other weather phenomena.
air mass - an extensive body of air that has about the same temperature and moisture distribution.
anemometer - an instrument designed to measure wind speed.
blizzard - wind speeds of at least 35 miles per hour and temperatures of 20 degrees Fahrenheit or less over an extended period. A severe blizzard means winds of 45 miles per hour and temperatures of 10 degrees or less.
celsius - a temperature scale where 0 degrees is the freezing point of water and 100 degrees is the boiling point.
clear skies - the state of the sky when less than one tenth is covered by clouds.
cold front - a zone where cold air is replacing warm air.
condensation - the process in which a vapor becomes a liquid or solid; the opposite of evaporation.
cyclone - an atmospheric low pressure system characterized by winds blowing inward in a counter-clockwise direction.
dewpoint - the temperature to which air must be cooled for saturation to occur; the temperature at which dew or frost will form.
disturbance - an agitation or disruption of the atmosphere, usually referring to a low pressure area and associated inclement weather.
dust storm - a severe weather condition characterized by strong winds and dust filled air over an extensive area.
evaporation - the process in which a liquid or solid becomes a vapor or gas. The opposite of condensation.
Fahrenheit - the standard temperature scale of the United States. Water freezes at 32 degrees and boils at 212 degrees.
flash flood - a flood that rises quite rapidly with little or no advance warning, usually the result of intense rainfall over a small area.
flash flood warning - flash flooding is occurring or imminent in the specified area.
flash flood watch - flash flooding is possible in the specified area.
front - the transition zone between two air masses.
frost - the condition when the earth's surface and/or objects on the earth fall below 32 Fahrenheit and ice crystals form.
heat wave - a period of abnormally hot and/or humid weather, that lasts at least one day and usually several days to several weeks.
high pressure area - a maximum of barometric pressure usually associated with favorable weather.
humidity - a percentage of moisture in the air compared to what it can hold at that temperature.
hurricane - a cyclone originating over the tropical oceans having torrential rains and winds greater than 75 miles per hour.
instability - a state of the atmosphere where air that starts to rise developing clouds and rain.
inversion - a reversal of the usual decrease in temperature with height.
jet stream - a zone of winds, concentrated in the upper atmosphere, blowing from west to east in the northern hemisphere. These winds act to "steer" our weather systems.
low pressure area - an area of minimum barometric pressure usually associated with inclement weather.
meteorologist - a person engaged in the study of some or various facets of the atmosphere.
monsoon - a name for seasonal winds. In Arizona, our winds shift to a more southerly direction in the hot part of the summer increasing humidly enabling the development of thunderstorms. July and August are the wettest months of the year in most of Arizona.
overcast - used when 95% or more of the sky is covered by clouds.
Pacific storm - an area of low pressure with origins in the Pacific Ocean.
partly sunny - when the sky is between four and seven tenths covered by clouds.
precipitation - all of the forms of water particles that fall from the sky and reach the ground.
rain - precipitation in the form of water droplets larger that 0.5 millimeters. Drops smaller than 0.5 millimeters are called drizzle.
ridge - an elongated area of relatively high barometric pressure.
severe thunderstorm - a thunderstorm with winds greater than 58 miles per hour and/or hail great than 3/4" in diameter.
severe thunderstorm warning - a severe thunderstorm has been sighted or indicated by radar.
severe thunderstorm watch - severe thunderstorms are possible in the specified area.
shower - precipitation that is characterized by rapid starts and stops or by rapid changes in intensity.
snow - precipitation in the form of white or translucent ice crystals.
stationary front - a zone between two air masses that shows little or no movement.
storm - a disturbed state of the atmosphere.
storm track - the path that a low pressure area follows.
temperature - the amount of heat or cold measured on a thermometer.
tornado - a violent, rotating column of air extending to the ground from a parent thunderstorm.
tornado warning - a tornado has been reported or is indicated by radar.
tornado watch - tornadoes are possible in the specified area.
tropical air - warm, humid air that develops over tropical and subtropical areas.
trough - an elongated area of relatively low barometric pressure.
virga - water falling from a cloud that evaporates before it reaches the ground.
visibility - the greatest distance in a given direction at which it is just possible to see and identify with the naked eye.
warm front - a zone where warm air is replacing cold air.
waterspout - a tornado that forms over water.
weather - the state of the atmosphere.
wind - air in motion relative to the earth's surface.
wind chill factor - the cooling effect caused by temperature and wind on bare skin.
wind direction - the compass direction from which the wind is blowing.
winter storm warning - a winter storm is imminent.
winter storm watch - a winter storm is possible.
