During Monday evening’s severe storms, sirens were sounded throughout many communities in central and southern Grant County, despite the fact that a Tornado Warning was not issued.
“Warning sirens are meant to notify people that they need to seek shelter immediately and turn on their TV or radio for information” said Steve Braun, Grant County’s Emergency Management Director. Although many people refer to them as ‘tornado sirens’, the sirens are also occasionally sounded for other severe weather threats. Based on the information available as the storms approached, Braun says that there was a clear and imminent threat to people’s safety which made it prudent to sound the sirens.
As the storm approached from the west, at 7:27 p.m. the National Weather Service issued the first of several Severe Thunderstorm Warnings for Grant County. The warning advised that the communities in the storm’s path could expect “70 mph wind gusts” and “ping pong ball size hail” and that “people and animals outdoors will be injured”. It also advised to “expect hail damage to roofs, siding, windows, and vehicles. Expect considerable tree damage. Wind damage is also likely to mobile homes, roofs, and outbuildings”.
As the storm entered the county in the Cassville area, the Grant County 9-1-1 Communication Center began receiving reports from fire and police officials of large trees and power lines down, and measured wind gusts of 65 miles per hour. That, according to Braun, is when the decision was made to sound the first round of sirens, in Lancaster, Stitzer, Potosi, and Dickeyville. As the storm progressed and more damage reports came in, sirens were eventually activated in Montfort, Livingston, Platteville, Cuba City, and Hazel Green ahead of the storm.
The radar signature for Monday’s storm was particularly ominous, according to Braun. The storm evolved into a bow echo, which are known for producing severe straight line winds and occasionally tornados, causing major and widespread damage.
“We try to reach a balance when activating the sirens”, Braun noted. “We don’t want to cry wolf or set them off for every thunderstorm, but at the same time we also don’t want to wait too long to get the warning out when the storm may be significant”.