Why did emergency sirens go off overnight when there were no tornadoes? Chris Edwards has the answer

(WXYZ) - Are you dragging a little today because sirens woke you up from a sound sleep? If so, you've got lots of company. Tens of thousands of metro Detroiters were jolted out of bed by warning sirens in the middle of the night. The first severe thunderstorm warnings were issued just after 2:15 am and the dangerous storms didn't clear the area until almost 4:30. During that time, the National Weather Service never saw any evidence of a tornado, and no tornado warnings were ever issued. So why did the sirens go off?

They were activated in many communities, especially in the northern suburbs, because the severe thunderstorm warnings mentioned the possibility of wind gusts to 70 mile per hour with the storms. These are "straight-line" winds, not associated with any twisting winds from a tornado. Many communities use the 70 mile per hour wind as a threshold; if the storms are capable of that much wind, they will alert their citizens by activating warning sirens, regardless of what time of day it happens. The communities make the decisions independently, which explains why your neighboring municipality may have stayed silent. This policy has been in place for several years, but many people continue to mistakenly call them "tornado sirens."

As damage reports today confirm, winds did indeed gust close to 70 miles per hour as the storms roared through. Many trees and power lines came down, leaving at least 140,000 homes and businesses without power. Even though we all value our sleep, the best thing to have done as the storms approached, whether sirens woke you or not, was to go to your designated safe place. For most of us, that's the basement or at least the lowest level of your house, away from windows and walls leading to the outside.

Winds of 70 mile per hour are as strong as a weak tornado, and have on many occasions delivered widespread damage and even death. No one wants to be alarmed needlessly, especially in the middle of the night, but the warning system has safety as the number one priority. That's also why Dave Rexroth and Keenan Smith were both in the Tracking Center as the storms arrived, bringing updates on-air, on-line and on Facebook and Twitter.

Warning sirens are just one way to alert you of dangerous conditions. Before you go to bed tonight, perhaps a little earlier than normal to catch up, you should make sure you have one of the very best ways to stay aware of severe weather. If you don't already have it, download Storm Shield to your mobile device here http://www.wxyz.com/weather/weather-news/wxyz-storm-shield-app. You may not have liked the timing of the storms last night, but the timing of our 40% sale for Storm Shield is perfect. And the sale only lasts as few more days, unlike severe weather season in Michigan, which has a long way to go.

Follow Chris Edwards on Twitter at twitter.com/ edwardswxwxyz

Print this article Back to Top

Comments