Hail Basics

Tuesday, April 26th, 2016

Oh my word, what a spring – From baseball size hail in San Antonio, TX area to grapefruit size hail (4 inches!) in the Wylie, TX area. Not to mention the hail that has fallen recently in Kansas, Iowa, California, Nebraska, Oklahoma, Missouri, Wisconsin, Ohio, Wisconsin, Michigan, Colorado, Wyoming, Illinois, Delaware just to name a few in the past week or so! So we thought we would do a little hail basics for all of those interested in the whys and hows of hailstorms.

What is hail and where does hail come from?

Now I know y’all know this, but not every thunderstorm has hail. The conditions have to be just right for hail to form. Hail forms when updrafts or the upward movement of air in thunderstorms carry precipitation, either sleet or raindrops, upward into very cold areas of the atmosphere; this is where the precipitation is able to freeze into balls of ice. What creates big hailstones is a very strong updraft, the one in San Antonio was 100+ mph, that is able to continue to lift the hail allowing the hail to continue to grow as it encounters other hail or more water droplets. When the storm’s updraft is not strong enough to keep the hail up, either due to the weight of the hail or the strength of the updraft weakens, the hail falls.

Hail can be any shape or size – from pea sized hail – approximately ¼ inch to softball size hail at approximately 4.5 inches. As I mentioned earlier, the size of the hail depends on the strength of the storm’s updraft. Usually, the bigger the hail the more irregularly shaped it will be due to the melding of several hailstones. Vivian, SD is the record holder of the biggest recorded hail; this hailstone was approximately diameter of 8 inches and a circumference of 18.62 inches. Then there was the crazy hail storm in Denver, Colorado, June, 2015 where people were shoveling several inches of hail – crazy!

Thunderstorms that produce hail are rampant in the spring and summer. This is due to the perfect “storm”, if you will, of warm surface temperatures that are essential in creating strong thunderstorms and cold upper atmosphere temperatures needed to create ice.

Professional roofing companies and insurance companies that help out with hail storm damage call the areas of hail damage hail swaths. This is in part because when viewed from the air, it is readily seen that hail falls in paths. These hail swaths come in all shapes and sizes from a couple of acres to areas that are 9-10 miles wide and more than 100 miles long. Piles of hail in hail swaths have been so deep, a snow plow was required to remove them, and occasionally, hail drifts have been reported.

What states are most affected by hail?

While every state has risk of hail, there are some states that seem to have more hailstorm damage claims; meaning these storms produce big enough hail to warrant homes and businesses getting new siding and roofing. These states are: Kansas, Nebraska, Missouri, South Dakota, Iowa, Colorado, Illinois, Texas, South Carolina and Pennsylvania. The central plains of the United States are most affected with large hail.

Estimating Hail Size


  • Pea = 1/4 inch diameter
  • Marble/mothball = 1/2 inch diameter
  • Dime/Penny = 3/4 inch diameter
  • Nickel = 7/8 inch
  • Quarter = 1 inch — hail quarter size or larger is considered severe
  • Ping-Pong Ball = 1 1/2 inch
  • Golf Ball = 1 3/4 inches
  • Tennis Ball = 2 1/2 inches
  • Baseball = 2 3/4 inches
  • Tea cup = 3 inches
  • Grapefruit = 4 inches
  • Softball = 4 1/2 inches

As we are in the throes of spring, hail is still in the forecast for this crazy year. Our years of experience in helping roofing contractors get leads has made MailStorm a go to in times of direct mail needs. We understand the need to get your name out to hail swaths quickly in order to help the communities that have been impacted by these hail storms. Contact us today for you hail postcards and hail door hangers. We look forward to helping you help others.