Partly Cloudy skies occur when 3/8ths to 5/8ths of the sky is covered by clouds.
Mostly Sunny skies occur when 1/8th to 2/8ths of the sky is covered by clouds. The term Mostly Sunny is only used during daylight hours, and is replaced with Mostly Clear at night.
Mostly Cloudy skies occur when 6/8ths to 7/8ths of the sky is covered by with clouds.
Virga are streaks of precipitation that fall from a cloud but evaporate before reaching the ground.
An Alberta Clipper is a winter low pressure system that moves southeast out of the Canadian Province of Alberta and quickly passes over the Plains, Midwest, and Great Lakes regions of the US.
These systems usually bring snow, wind, and colder temperatures with it.
Humidity measures the amount of water vapor present in the air.
Also known as a Twister, a Tornado is a spinning column of air that reaches the ground. This is different from a Funnel Cloud, which is the same as a tornado but has not touched ground.
A Red Flag Warning is a term used by fire-weather forecasters to call attention to limited weather conditions that may result in extreme burning conditions. Red Flag criteria occurs whenever a geographical area has been in a dry spell for a week or two, or for a shorter period , if before spring green-up or after fall color, and the National Fire Danger Rating System (NFDRS) is high to extreme.
A Red Flag Warning is issued during an on-going fire event or when the fire weather forecaster has a high degree of confidence that Red Flag criteria will occur within 24 hours.
A Fire Weather Watch is issued when conditions are forecast to be favorable for a Red Flag Warning. This means that there could be low relative humidity and warm temperatures.
RADAR stands for Radio Detection and Ranging. Radar uses radio waves that reflect off of objects to determine the distance to an object by the strength of the returning signal. In weather terms, Radar is used to measure distance, speed and direction of precipitation.