Severe thunderstorms rolled across northeast Iowa this morning producing damaging hail. The worst of it was in Hardin, Grundy, and Black Hawk counties where hundreds of dollars in damage occurred in less than an hour as the system moved from west to east.

Mark Schackenberg is the chief meteorologist at KWWL-TV in Waterloo, and says there are reports of hail stones as large as ping pong balls. “In certain spots, in the heavier cell of this, it did produce one and half inch hail for about five minutes –five to six minutes,” Schackenberg says, “It started to hail with small hail and eventually became large hail and it came down heavy and eventually that hail tapered off and we had just Rain. And now we have all the damage out there now.”

Schnackenburg says storms like this are why the National Weather Service thunderstorm warnings need to be taken seriously. “They really mean business now because the criteria for the hail size is a bit larger than it was a couple of years ago,” according to Schnackenberg.

He says the studies show saw that severe damage can come from one inch diameter sized hail to do any significant damage compared to the three quarter inch sized hail. Schnackenberg says the hail covered the ground for a couple of hours making driving and especially walking treacherous.