The temperature of a ground surface (e.g. black top, concrete, grass) at a specific time and location. #WeatherTerms
A measure of the coldness or warmth at a specific time and location expressed in either Fahrenheit (F) or Celsius (C) degrees. #WeatherTerms
Precipitation in the form of ice crystals. It originates in clouds when temperatures are below the freezing point, when water vapor in the atmosphere condenses directly into ice without going through the liquid stage. Once an ice crystal has formed, it absorbs and freezes additional water vapor...
Wet snow with a water content in excess of 30%. It has no compressive strength but can refreeze, creating a hazardous condition. #WeatherTerms
Frozen raindrops. Sleet occurs when rain falls through a deep enough layer of the atmosphere to freeze before reaching the ground surface. It can occur when surface temperatures are either above or below freezing; and unlike freezing rain, sleet hits the ground as frozen ice pellets that can...
A system that comprises automatic weather stations (referred to as environmental sensor stations) in the field; a communication system for data transfer; and central systems to collect field data from numerous stations. These stations measure real-time atmospheric and pavement temperatures,...
The amount of water vapor in the air relative to what it could hold at a given temperature. #WeatherTerms
The hardening process that occurs by breaking up the layers and particles of snow is accelerated by mechanical agitation, which occurs either from wind action causing drifting snow or plowing. This effect has very practical implications in snow management. For example, the time and effort in...
Another consequence of Temperature Instability of snow is its change in structure with time. An undisturbed snow mass will densify (decrease in volume) and increase in hardness and compressive strength. The snow crystals will then grow, causing the bond strength between crystals to drop...
Temperature Instability affects the amount of liquid coating the snow particles, which in turn influences compressibility , hardness , density and cohesiveness . This characteristic is probably the most important factor affecting its properties, and thus the most important factor affecting...