BILOXI, Miss. (WLOX) -While summertime thunderstorms are a part of life in South Mississippi, they can still cause problems. One of the biggest threats with thunderstorms in the summer time are downbursts.
Downburst winds were likely to blame for tree limb and minor roof damage in parts of Harrison and Jackson counties Wednesday, June 27, 2019.
So what is a downburst?
Thunderstorms form when warm air rises, cools, condenses and forms clouds. Eventually enough moisture gathers in the cloud to fall to the surface as rain.
Sometimes, a layer of dry air can get entrained into the thunderstorm cloud.
When rain falls through this layer of dry air, it evaporates and rapidly cools. This cool air is very dense and rushes down to the surface, sometimes violently.
How large are they?
Downbursts fall into two categories: macorburst and microburst. A microburst is typically have a radius of strong winds of about 2.5 miles. While a microburst has a radius of strong winds greater than 2.5 miles. Downbursts typically are responsible for wind damage in very small areas. One block may see just heavy rain, while one block over trees are knocked down.
How strong can they be?
For winds to be considered severe, they must be at least 58 mph or greater. Some downbursts can produce winds up to 150 mph and produce as much damage as a tornado.
Hail often accompanies downbursts
How does hail form?
Hail forms when upward moving winds inside a thunderstorm called updrafts keep water particles suspended high in the cloud where it is freezing.
The particles freeze then start to fall. But updraft winds through the hail back up into the cloud and another layer of ice forms.
Eventually the ice grows so large, the updraft can not hold it in the cloud anymore and it falls to the ground as a chunk of ice. Sometimes violently at speeds of over 80 mph.