Do you know the difference between a hurricane and a typhoon? Find definitions for weather terms from absolute humidity to zonal flow and everything in between in the WeatherBug weather glossary.

Wall Cloud

A localized, persistent, often abrupt lowering from the base of a parent cloud. Wall clouds can range from a fraction of a mile up to nearly five miles in diameter, and normally are found on the south or southwest (inflow) side of the thunderstorm. When seen from within several miles, many wall clouds exhibit rapid upward motion and cyclonic rotation.

More Glossary Terms:

• Variable
• Variance
• Veering Winds
• Virga
• Visibility

• Warm Advection
• Warm Cloud
• Warm Front
• Water Vapor
• Waterspout