Severe thunderstorm watch issued for SE Michigan: Everything you need to know

Metro Detroit weather: Tracking storms on June 10, 2020

DETROIT – The Storm Prediction Center has issued a severe thunderstorm watch for all of southeast Michigan until 8 p.m. Wednesday.

The weather scenario appears to be playing out as expected and, even though the watch was issued early this afternoon, I still think the main threat will be from 4 to 8 p.m. While I cannot categorically rule out a storm between 2 and 4 p.m., I expect a significant increase in storm coverage by mid-afternoon just to our west, with a substantial area of storms crossing our area between 4 and 8 p.m.

The most widespread severe weather impact will be high-end damaging wind gusts -- some of which could even approach 75 mph. Keep in mind that this wind speed is the same speed as an EF0 tornado -- the only difference is that a severe storm’s winds blow in a straight line, while a tornado’s wind rotates.

Or, if this steamy airmass has you thinking about the tropics, a 75 mph wind is Category 1 hurricane strength. Not all of the storms will have this strong of a gust, but the potential is there.

Although this is a Severe Thunderstorm Watch, that does not mean that tornadoes are not possible. Our wind aloft is marginally conducive for tornadoes, so it IS possible that a tornado or two could develop in the watch area.

Some of the storms will also have large hail -- possibly as large as ping pong balls in the strongest storms.

Obviously, frequent lightning and torrential downpours are a given.

Here are some key messages I want you to keep in mind this afternoon:

  • Know where your place of safety is NOW -- plan ahead in case you need to quickly move to shelter later, especially if a Tornado Warning is issued.
  • Remember that some communities sound their sirens if a severe thunderstorm with 70+ mph wind gusts are expected. So not every siren this afternoon will be a tornado alert, but you need to take it just as seriously.
  • These storms will be fast movers -- they will get from the horizon to you in short order, so you have less time than you think to take cover if you’re outside.
  • There will likely be a lot of power outages...PLAN FOR THIS. Keep your devices charged, and fresh batteries on hand for flashlights should your power go out.
  • Some storms will have large hail so, if this is an option for you, park your car in a garage or under a carport.
  • There will be torrential rain in these storms. While this can cause localized urban flooding, I do not expect widespread areal flooding like we get after a big 2-4-inch rain event.
  • Always respect lightning! If you are outside and hear thunder, then lightning is close enough to strike matter how “faint” the thunder sounds. Remember that lightning can strike you TEN MILES from a storm.

One final very important message: If you are trying to get some things done outside, and are rushing to “beat the storm” before heading inside as soon as you feel the first raindrops, DON’T WAIT FOR THE RAIN. Most severe thunderstorms’ dangerous wind gusts rush out AHEAD of the storm and hit you before the rain starts.

The Local4Casters have you covered this afternoon. We’ll keep you updated on Local 4 and on, and you can follow the storms’ progress yourself on our FREE Local4Casters Weather App radar. Just search under WDIV in the App Store -- you’ll see it right there.

And I will be tweeting personalized updates through the afternoon -- follow me on Twitter at @PGLocal4.