Friday storms in Metro Detroit: Breaking down hail, wind, tornado threats

4Warn Weather – Showers and storms are set to arrive in Southeast Michigan in the mid-afternoon on Friday, and should last through the night.

That wet weather has the potential to be severe, and could create some hazardous conditions like strong winds and hail.

Below, we’re breaking down the severe weather risk and threats for Friday, Aug. 11 with the help of 4Warn Meteorologist Ashlee Baracy, and the National Weather Service’s Storm Prediction Center.

Different risk levels in SE Michigan

Southeast Michigan is risk for severe weather on Friday, but the risk level varies depending on the area.

The Storm Prediction Center initially placed most of Michigan under a “marginal risk” for severe weather on Friday. This risk level, the dark green coloring on the map below, is the lowest category on the spectrum (level 1 of 5).

However, an updated forecast shows much of the southern Lower Peninsula, including Southeast Michigan, has been upgraded to a slight risk (level 2 of 5) for severe weather. That risk level is indicated by the yellow on the map below.

Meteorologists predict that multiple rounds of thunderstorms will move across all of Southeast Michigan Friday afternoon and Friday night. Storms are expected to arrive mainly after 3 p.m., and more severe weather is expected later in the evening. Isolated severe, or near severe, storms are possible.

To the west of our state, portions of multiple states are under a slight risk or enhanced risk (level 3 of 5) for severe weather. Several parts of the U.S. are at risk for thunderstorms (the light green shade), but those aren’t expected to be severe.

Specific severe weather threats

Any severe storms that arrive in Metro Detroit on Friday have the potential to create some hazardous conditions in the area.

Wind gusts could exceed 60 mph. Hail greater than 1 inch in size is possible. The region will experience a few downpours, and there is also a low tornado threat.

We’re breaking down the specific threats in some more detail below.

Wind outlook

• According to the Storm Prediction Center, strong winds are among one of the largest risks associated with Friday’s potentially severe storms.
• Isolated wind gusts around 60 mph are possible during the storms. Winds moving at this speed are capable of causing considerable damage to structures, especially roofs, small trees and more.
• If multiple storm cells move in a linear motion across the region, as is possible Friday, damaging wind is the most likely hazard. Strong winds are particularly possible Friday night.

Hail outlook

• Large hail may fall during the thunderstorms.
• Isolated hail has the potential to reach 1-inch diameter in size -- about the size of a quarter.
• Hail this size is capable of causing minor damage.

Tornado outlook

• There is a chance for a weak, isolated tornado in Southeast Michigan on Friday.
• This risk is primarily for those west of US-23, and shouldn’t affect most of Metro Detroit.
• A bit further away, the Storm Prediction Center forecasts a 2% chance of a tornado just southwest of Michigan, primarily in northern Illinois. See the map of the risk below.