Thursday, 23 May, 2013

Typically, the swirl of stormy weather obscures the cells at the heart of severe thunderstorms. This uncommonly clear view of an entire thunderstorm cell, with the top of the growing cumulonimbus tower topping out at 40,000 feet, reveals many interesting features, including “fall streaks” of what may be hail from the underside of the overhanging anvil portion of the cloud. Shortly after this photo was taken on May 22, 2011, near Madison, the storm pelted the Sun Prairie area with large, damaging hail.

Tornadoes need wet air, dry air, and wind shear. What explains the big improvement in tornado prediction? Is climate change boosting these storms?

What are the different types of thunderstorms? Thunderstorms can be classified by severity or structure. For example, the National Weather Service defines a severe thunderstorm as one that produces one or more of the following: wind gusts of at least 58 mph, hail at least one inch in diameter, or a tornado. A supercell thunderstorm [...]

How many lightning bolts hit Wisconsin each year? Multiple cloud-to-ground lightning captured by C. Clark for NOAA with time-lapse photography. Wisconsin gets hit by lightning about 300,000 times a year; most of that during the spring and summer. That’s about five flashes for each square mile in the state. For about 20 years, the continental [...]

Scott Bachmeier, a research meteorologist at the Cooperative Institute for Meteorological Satellite Studies at UW-Madison, says that particles in the air scatter light. In the day, the particles scatter more violet and blue light, but our eyes are more sensitive to blue light — that’s why the sky appears blue. Thunderstorms, which can be the [...]