Dry thunderstorm facts for kids
A dry thunderstorm is a type of thunderstorm where there is lightning and thunder, but most or all of the precipitation does not reach the ground. They usually happen in deserts or areas with low water vapor. Because dry air usually absorbs liquid water, the rain is absorbed before it reaches the ground. They happen a lot during the summer months in western North America.
Dry thunderstorms are dangerous because they can cause dust storms and wildfires. Dust storms can happen because the dry soil and sand are picked up by strong winds. Wildfires can happen because the lightning can hit trees and there is no rain to put out the fires.
Hazards
Dry thunderstorms are notable for two reasons: they are the most common natural origin of wildland fires, and they can produce strong gusty surface winds that can fan flames.
Dust storms
Strong winds often develop around dry thunderstorms as the evaporating precipitation causes excessive cooling of the air beneath the storm. This cool air then descends rapidly and fans out upon impacting the ground, an event often described as a dry microburst. As the gusty winds expand outward from the storm, dry soil and sand are often picked up by the strong winds, creating dust and sand storms known as haboobs.
Fires
In areas where trees or other vegetation are present, there is little to no rain that can prevent the lightning from causing them to catch fire. Storm winds also fan the fire and firestorm, causing it to spread more quickly.
Pyrocumulonimbus are cumuliform clouds that can form over a large fire and that are particularly dry. When the higher levels of the atmosphere are cooler, and the surface is thus warmed to extreme temperatures due to a wildfire, volcano, or other event, convection will occur, and produce clouds and lightning. They are similar to any cumulus cloud but ingest extra particulates from the fire. This increases the voltage difference between the base and the top of the cloud, helping to produce lightning.
