Make no mistake, we get heavy weather from time to time in Michigan, but this is not tornado alley. Normally sheltered and buffered by the surrounding Great Lakes, we are not generally subject to the kind of extremes that are more common in neighboring midwestern states.
Buffalo might get six feet of snow, but we get 12 or 16 inches. In Wisconsin it might be -16 F, and here it’s zero. Tornado chasing is not a thing here.
Most of this summer has been luxuriantly mild, moist and without extremes, but in the past week there have been some brushes with weather that pushed the envelope. It’s the kind of thing that makes a normally oblivious citizen go “hmmmm..” Social media was buzzing with “..biggest I’ve ever seen..” stories.
One particularly intense node of the storm swept thru Sleeping Bear National Lakeshore, and nearby Traverse City – where a film festival was in progress, and a friend who was there described it cinematically as “something from a Michael Bay movie“.
GLEN ARBOR, MI — In the hardest hit areas of the Sleeping Bear Dunes National Lakeshore, Sunday’s storm has all but destroyed sights enjoyed for decades by millions of visitors.
“It’s pretty devastating there,” park ranger Merrith Baughman said about DH Day Campground and the Glen Haven area.”Some people won’t really recognize them.”
“We have heavy tree damage,” she said. “Big, old trees are down in multiple areas.
Hail nearly the size of a baseball in West Branch, MI – August 2, 2015
Glen Arbor, Sleeping Bear Dunes and much of Michigan were raked with widespread severe weather Sunday. But why was this particular outbreak so destructive?
Michigan is on the edge of “severe weather alley” in the middle U.S. So we don’t often see record-setting baseball-sized hail. We get our fair share of thunderstorm winds, causing damage to isolated areas.
But this severe weather outbreak had four rounds of severe thunderstorms. That’s really amazing to me as a meteorologist. Most of the time, storms here in Michigan is “one and done” – one round of storms and then the atmosphere stabilizes and can’t brew another batch.
Not Sunday, August 2, 2015. The radar loop below from the National Weather Service in Gaylord, MI. shows four lines of storms moving across northern Michigan.
So here are the reasons each type of severe weather was produced.
Why the record hail size?
Hail is formed in the part of the storm aloft where temperatures are cold and water can freeze. There was a large part of the baseball-sized hail storm in West Branch where temperatures were below freezing. Hail is formed when water droplets in the storm are sucked into the updraft in the middle of the storm. The droplets were then shoved upwards to the top of the atmosphere, where temperatures where -58°F. That’s not a typo.
Normally, when the hailstone grows large enough that the updraft can’t hold the hail in the air, the hail falls. A baseball-sized hailstone needs an updraft of 120 mph to keep it suspended. Could you imagine flying through a severe storm and hitting an updraft going 120 mph? It would make all roller-coasters look like kiddie rides. Obviously that’s why the airliners fly around the worst part of thunderstorms.
So the extreme hail was caused by a perfect mix of extreme energy, and very strong updrafts.
What about the straight-line winds?
Destructive winds yesterday were caused by some of the same factors causing the hail. We talked about the strong updraft. Also, yesterday’s horizontal winds at 30,000 feet up were 100 mph. The updraft hit the 100 mph jet stream and got re-directed toward the ground. Now, a heavy, colder, moisture laden swath of high winds is heading right toward the ground. That’s a textbook case of straight-line winds.
Tornadoes also?
Right now there is only one confirmed tornado from yesterday’s severe weather. Tornadoes need wind shear to form. Wind shear is mostly described as wind from different directions at varying heights in the atmosphere. Yesterday’s tornadoes were likely caused by lake breezes, and an abrupt shift in wind direction in the lower part of the atmosphere. That’s why the Thumb is a typical place for tornadoes to occur. The lake breeze comes inland, and interacts with a storm, causing rotation.
One reason for this post is that, in my own neck of the woods, just a week before, we experienced a rain event significant enough for me to pull out a camera to record it. Although I’ve seen heavier floods from longer lasting rains, it’s hard to remember an event where this much water came down, this fast.
Data from the US Global Change Research project shows that it’s not an illusion. The upper midwest has gotten significantly heavier rains over recent decades.
3 thoughts on “Heavy Weather in an Unexpected Place”
Just had some “heavy weather” blow through NO VA. High winds, an inch or two of rain in ten or fifteen minutes, marble-sized hail, downed branches and leaves all over the place. I live at the crest of my street, and it slopes away gradually in both directions. The rain was so heavy that it was two+ inches deep in the gutters as it ran off. More clusters of storms are still coming in from WV.
This is getting to be the pattern here—-not a single “normal” storm that might last half an hour, but very intense and scary things, and they often come through in trains. Yada-yada on the TV, flash flood warnings all the time—this is the “new normal” here in northern VA, where we are on the line between the 27% and 72% zones on the precipitation change map.
It is different now. You used to drive through puddles at the bottom of a hill now you drive through big puddles going up the hill. Places that never flooded because the drainage was plenty good now flood. True the water goes away fairly quickly, an hour or two, but it did not accumulate a decade ago.
Notice the great increase in New England, up 71%. Extreme weather in NH gets almost no national attention — the exception being the recent tent collapse in Lancaster. Serious floods have come this century that were associated with plain old rainstorms and in areas that had no identified needs for flood control previously. 20th century floods were associated with either hurricanes — the 1938 one was a monster — or sudden snow melts. Inch/hour rainstorms were unknown before.
Just had some “heavy weather” blow through NO VA. High winds, an inch or two of rain in ten or fifteen minutes, marble-sized hail, downed branches and leaves all over the place. I live at the crest of my street, and it slopes away gradually in both directions. The rain was so heavy that it was two+ inches deep in the gutters as it ran off. More clusters of storms are still coming in from WV.
This is getting to be the pattern here—-not a single “normal” storm that might last half an hour, but very intense and scary things, and they often come through in trains. Yada-yada on the TV, flash flood warnings all the time—this is the “new normal” here in northern VA, where we are on the line between the 27% and 72% zones on the precipitation change map.
It is different now. You used to drive through puddles at the bottom of a hill now you drive through big puddles going up the hill. Places that never flooded because the drainage was plenty good now flood. True the water goes away fairly quickly, an hour or two, but it did not accumulate a decade ago.
Notice the great increase in New England, up 71%. Extreme weather in NH gets almost no national attention — the exception being the recent tent collapse in Lancaster. Serious floods have come this century that were associated with plain old rainstorms and in areas that had no identified needs for flood control previously. 20th century floods were associated with either hurricanes — the 1938 one was a monster — or sudden snow melts. Inch/hour rainstorms were unknown before.