Thunderstorms feed off of warm, unstable air that is often present during spring and summer as well as autumn in this part of the country. While the air may be well above freezing at the surface, that is not the case thousands of feet aloft. As a thunderhead towers higher into the atmosphere, it eventually reaches the freezing level.
Within the storm, there are different regions where winds rush up into the storm updraft and accelerate towards the ground downdraft. Raindrops inside the storm are carried along with the wind currents. When conditions are favorable for it, those raindrops can be carried up into the mid to upper portions of the storm, where the air is below freezing. Naturally, the raindrop will freeze and eventually fall back down below the freezing level.
As this small ice pellet collides with other raindrops, it accumulates an outer layer of liquid water. The ice pellet can often get recaptured in the updraft again and again, getting thrust into the upper reaches of the storm each trip up while also adding outer layers of water freeze. A hailstone begins as a water droplet that is swept up by an updraft inside of a thundercloud. Inside the cloud, there are a large number of other supercooled water droplets already present.
As the water droplet reaches higher elevations within the cloud it comes into contact with more and more supercooled particles. This is because it is at the highest parts of the cloud, where the temperature is too low at least 32 degrees Fahrenheit for water molecules to remain in either a liquid or gaseous state.
The hail embryo will grow larger and larger as it reaches higher altitudes in the updraft. The hailstone will reach a size and weight where gravity will begin to act on it and pull it down. However, this is not necessarily the end of its formation, as it could be pulled into another strong updraft and remain in the upper part of the cloud.
For example, a May hailstorm in Texas injured people when they were caught outside during Mayfest with very little shelter available; 60 of those injured required hospitalization. Even hail storms that produce a lot of small hail can be dangerous because all those hailstones can completely cover roads. If these hail piles are deep enough, they can prevent car tires from touching the road at all. This makes driving conditions similar to icy winters. The best way to protect yourself from a hailstorm is to be prepared, especially if you live in a hail-prone region.
If severe weather occurs, such as a bad thunderstorm, tune in to the radio or another news source to make sure you stay up to date of any immediate threats to your family or property. Make sure you stay inside until the hail stops and stay away from skylights and windows. Close the drapes or curtains if you have them to keep broken glass and hailstones out of your home.
Avoid trees because they can lose branches during thunderstorms and isolated trees can also attract lightning. Daily 11 Today. Thunderstorm Safety and Preparedness. By Simone M. Scully April 20, A very severe hail storm with wind driven baseball- sized hail destroyed property in eastern Nebraska on June 3, Typically large hail just falls straight down, mostly damaging roofs, but in this photo, we see a rare case of the damage done when big hail was pushed along by strong straight line winds.
Extreme hail storm falling on the high plains of Nebraska. This extreme weather event caused damage to vehicles and property.
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