GRAND RAPIDS, Mich. (WOOD) — May 31, 2023 was the 25th anniversary of the famous “derecho” thunderstorm outbreak of 1998.

A derecho (Spanish for “straight”) is a fast-moving line of severe thunderstorms that produces a wide and long swath of significant wind damage. Around 5 a.m. that Sunday, the storms blasted through West Michigan with winds estimated as high as 130 mph in Grand Haven, Spring Lake and Walker. According to the Storm Prediction Center, this episode ranks as one of the top thunderstorm events in world history!

From the Storm Prediction Center: “The leading edge of the derecho reached the eastern shores of Lake Michigan around 4:45 a.m. EDT Sunday and blasted across Lower Michigan at a speed of about 70 mph. It reached the “Thumb” area in a little over 2 hours (Figure 1). Winds of 60 to 90 mph were common; in some areas, winds were estimated to have reached 130 mph. Of all the regions affected by the derecho, the greatest damage and the greatest number of casualties occurred in Lower Michigan. In this region four people were killed and 146 were injured (not including those who self-treated). Total damage was estimated to be $172 million (1998 U.S. dollars). Approximately 250 homes and 34 businesses were totally destroyed, and over 12,000 homes and 800 businesses were damaged. About 860,000 customers lost electrical power. This was a new historical record, slightly exceeding the number of customers that lost power during the Southern Great Lakes Derecho of 1991. In some locations power was not restored for up to 10 days. For Consumers Energy, the utility company that serves much of western and middle Lower Michigan, this derecho was the most destructive weather event in the company’s history. Besides the loss of hundreds of power poles and lines, five of the company’s 345-kilovolt transmission towers were blown down between Ludington and Grand Rapids. These massive towers were designed to withstand continuous winds up to 90 mph and gusts to 110 mph.”

A large area of significant wind damage occurred from South Dakota all the way to the East Coast. At one point, not a single stoplight was working between Grand Rapids and Baldwin. The toll would have been much higher if the storms came in the afternoon instead of in the early morning when most people were asleep in their homes.

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Radar loop of the storms as they blasted across the Midwest and Great Lakes

The initial supercells formed in South Dakota Saturday afternoon the 30th. These supercells eventually formed the line that raced from eastern S.D. to Massachusetts and out into the Atlantic Ocean. Twenty years later you could still identify swaths where most of the trees were blown over (White Lake exit on US 31 – the Spring Lake Cemetery). Here’s a radar loop from South Dakota to Michigan. Read more here, here, and here. Storm Reports here (pages 2 – 8). The 1998 storm was a “once in a lifetime event.”

I went out to visit Spencer, South Dakota, where the worst tornado occurred as the supercells first formed. That small town was pretty much wiped out. Only two blocks in the entire town were spared significant tornado damage. The tornado was an EF4 and was the most destructive tornado in the history of the state. The tornado occurred at sunset and afterward it was soon dark. It was mid-morning before some of the victims were found. A portable Doppler radar indicated winds of 220 mph with that tornado. In a town of 315, there were six fatalities and nearly half the town residents who where there that night were injured. The population of the town dropped to 145 after the tornado.

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Wind damage reports from May 31, 1998

Area of Lower Michigan affected by the worst damage from the May 31, 1998 derecho. Each plus sign is where significant wind damage occurred, based on a damage survey by Grand Rapids NWS Forecast Office meteorologists.

Radar of the derecho crossing Lower Michigan

I talked with Robert Johns, who was a lead forecaster at the Storm Prediction Center. He said they issued tornado watches instead of severe thunderstorm watches for Wisconsin and Michigan, anticipating tornado-like damage from the derecho.

Actual record wind gusts in red, estimated in tan.

The numbers on the map above are wind gusts from the storm. Those marked in red were measured gusts; those in tan were estimated wind gust speeds. The estimated gusts were based on damage surveys by Grand Rapids NWS Forecast Office meteorologists. Thirteen Michigan counties (noted in black lettering and within light blue border) together were declared a Federal Disaster Area by the Federal Emergency Managers Association.

The purple “S” represents where a “seiche” took place on the eastern shore of Lake Michigan. Derechos crossing Lake Michigan occasionally produce what is called a seiche (pronounced as “say-sh”). A seiche is a pronounced oscillation of the lake surface. Such oscillations can at times change the water level at a given point by as much as 10 feet. The May 30-31, 1998, derecho produced a seiche as the water level rose on the east side of the lake because of the intense westerly winds. At the time the derecho hit the east shore, a tug boat, the Stephen M. Asher, was traveling through a channel between Lake Michigan and White Lake north of Muskegon (the purple “S” above). The sailors on board the tug noticed the surge and the rise in water level as the derecho winds moved through. However, after the winds had subsided, the boat received an even higher surge from the opposite direction as the water in White Lake tried to return back down the channel into Lake Michigan. It was this return surge that overturned and ultimately sank the boat. Fortunately, the sailors were able to reach the bank of the channel and no one drowned.

I would be surprised if we saw an event of that intensity (130 mph wind gusts in Grand Haven and Walker) and widespread area again in my lifetime. Here’s pictures from Grand Haven after the storm.

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Damage to condominiums in Spring Lake
Frequency of Derechoes in the United Sates

Here’s a summary of fatalities and injuries from the Iowa derecho of Aug. 10, 2020. This does not include injuries that occurred after the event (there are sometimes more injuries after a derecho than during the storm).

A final note: In 1998, there were four major derechos across the Great Lakes states. This one was the worst. Storm Team 8 will be tracking storms this summer. We’ve had a pretty quiet spring for severe weather in West Michigan so far. Let’s hope that continues.