Archives
Categories
WeatherGuys Links
Monthly Archives: April 2026
What is the tornado scale?
A tornado is a powerful column of winds that rotate around a center of low pressure. The winds inside a tornado spiral inward and upward, often exceeding speeds of 300 mph. We classify the strength of a tornado after trained observers assess the damage it did to the area.
All tornadoes are assigned a single number from the Enhanced Fujita Scale (EF) according to the most intense damage caused by the storm. When tornado-related damage is surveyed, it is compared to a list of damage indicators and degrees of damage to help estimate the range of wind speeds the tornado likely produced. The rating is assigned based on a set of 28 damage indicators, such as barns, schools and trees; the degree of damage to each one is used to determine the EF scale of every tornado. Continue reading
Why do clouds turn green during some storms?
The visible light spectrum covers colors from violet to red. Each color corresponds to a different wavelength, with green sitting roughly in the middle. Blue and violet have shorter wavelengths. Light rays change direction when they hit particles — a process known as scattering. The sky looks blue because air molecules scatter shorter wavelengths more effectively.
Clouds are made of water drops and ice crystals that scatter light from the sun in all directions. It is the multitude of drops and crystals that make a cloud look white during the day. Sometimes only a small amount of light escapes out the bottom, and so cloud bottoms often appear grayish. Continue reading
Category: Meteorology, Phenomena, Severe Weather
Comments Off on Why do clouds turn green during some storms?
Comments Off on Why do clouds turn green during some storms?
What is the shape of raindrops?
While cartoonists typically draw raindrops like a teardrop or a pear shape, raindrops are not shaped like that.
They are drawn as teardrops to give the image of falling through the atmosphere, which they do. But as they fall, raindrops are flattened and shaped like a hamburger bun by the drag forces of the air they are falling through. Continue reading
How is air quality measured and what are the trends in Wisconsin?
The amount and density of pollutants in the air are converted into an Air Quality Index, or AQI. The Wisconsin Department of Natural Resources’ statewide monitoring network is operated following a federally approved plan. The DNR statewide network includes 30 ozone and 18 fine particle, or PM2.5, monitoring sites. PM2.5 describes particles with diameters that are generally 2.5 micrometers or smaller and thus inhalable.
Under the Clean Air Act, the Environment Protection Agency sets National Ambient Air Quality Standards for pollutants. Continue reading
