WeatherWeather Science


Ever wonder how fast hail falls?

Hail Speeds
Severe Thunderstorm Watch tweet
Posted at 5:35 PM, Jun 08, 2022
and last updated 2022-06-09 00:24:25-04

The frequency of large, damaging hail peaks in intensity in our region in June, with July being the next busiest month.

Tuesday's severe weather outbreak coming during the peak month of hail season.

When posting to social media on Tuesday, I had a viewer ask about the speed at which hail falls.

Severe Thunderstorm Watch tweet
Severe Thunderstorm Watch tweet from Alan Rose and reply from KOAA 5 viewer Mike Hoffman

In response to my tweet about the potential for tennis ball size hail, Mike Hoffman said, "Good Lord. Tennis ball sized hail? How would anything survive that insanity? What is terminal velocity for hail that large?"

Well it got me thinking...and NOAA's National Severe Storms Laboratory has research dedicated to this topic.

So, let's break it down...

Hail Speeds
The speed at which hail falls to the surface vs. the size of the hailstone

Small hailstones pea to quarter size, or roughly less than an inch in diameter, can fall at speeds of 9-25 mph.

The larger the hail, the faster it falls.

That said, let's now examine larger hailstones typically found in severe thunderstorms that range from quarter to golf ball size.

These stones can reach speeds of 25-40 mph.

Giant hailstones as large as 2-4" in diameter that can be compared to such things as limes to softballs, these can hurtle towards Earth at speeds of 44 to 72 mph.

Finally, for monster hail larger than 4" in diameter, it's possible that these hailstones can fall at speeds as fast as 100 mph.

It's important to note that there is a margin of error in these numbers due to things like the shape of the hailstone, degree of melting, the direction it's falling, and atmospheric conditions as the time of the storm.

With severe weather season peaking later this month, it's always best to know the risk of hail before planning any outdoor activities, especially during the afternoon hours.

For that, you can turn to First Alert 5 for the very latest.