Editor’s note: Below is an article I wrote that appears in this month’s Allen County HamNews, the joint newsletter of three Fort Wayne amateur radio clubs.

A garden-variety thunderstorm blew through Allen County at midday on July 18. It was strong enough to prompt the northern Indiana office of the National Weather Service (IWX) to issue a Special Weather Statement but not a Severe Thunderstorm Warning. Gusts during the storm resulted in someone reporting to IWX that winds were “well above severe limits.” IWX meteorologists doubted that, with good reason.

At about the same time, my rooftop anemometer on the northeast side of Fort Wayne measured a peak gust of 22 mph — well below the 58-mph minimum severe thunderstorm criteria. I was surprised, because that gust really sounded more impressive from inside our house. When I looked around our yard, however, I didn’t even see any small twigs on the ground.

The “well above severe limits” wind estimate prompted IWX to share on Twitter a post with a picture of the Beaufort Wind Chart, which helps storm spotters estimate wind speeds based on what they see the wind do. That chart indicates that winds in the range of 55 to 63 mph (around the lower end of severe storm criteria) usually uproot trees and cause “considerable structural damage.” I doubt that the person who reported winds “well above severe limits” observed either of those phenomena.

Research published in the Journal of Applied Meteorology and Climatology and reported on by the online earth and space news site Eos, indicates that people “overestimated the speeds of wind gusts—on average, by about one third of the gusts’ actual speeds.” Researchers also found flaws in the Beaufort scale, but as IWX tweeted, “informed estimates are much better than a guess.”

We storm spotters don’t always have access to anemometer data, but there’s something we can do that will be much more valuable to the National Weather Service than even informed estimates of wind speeds. What is it? The answer is fairly simple and the clue comes from the Beaufort chart.

Rather than reporting an estimated wind speed, we can report what we see the wind do.

If we see the wind uproot a tree, we can report that a tree was uprooted, its approximate size and whether it appeared to be healthy or rotted.

If we see the wind damage a structure, we can report the visible damage (e.g. shingles blown off a roof).

We don’t even need to look up wind speeds on the Beaufort chart, because National Weather Service meteorologists have their own copies. A clear description of what the wind did enables National Weather Service meteorologists to determine — with the help of radar velocity data — what the wind speed probably was. More importantly, a clear description of wind damage helps meteorologists determine whether to issue or extend a Severe Thunderstorm Warning.