May 12 derecho unleashed 6 tornadoes on western Minnesota, eastern North Dakota
A weather phenomenon known as a derecho unleashed damaging wind storms across the region last week. Not only is this massive wind storm relatively rare, but it is unusual for it to form so early in the season.
GRAND FORKS — The National Weather Service in Grand Forks has confirmed a mega-storm known as a “derecho” unleashed at least six different tornadoes May 12 on eastern North Dakota and western Minnesota.
The National Weather Service defines a derecho as a “widespread, long-lived wind storm that is associated with a band of rapidly moving showers or thunderstorms.”
Although the derecho can produce destruction similar to that of tornadoes, the weather service says the derecho’s damage typically is directed in one direction along a straight swath. As a result, the term “straight-line wind damage” is sometimes used to describe derecho damage.
Last Thursday evening’s rash of storms and hurricane-force winds uprooted and destroyed trees; snapped power poles like matchsticks, and damaged buildings, outbuildings and vehicles throughout the region. No lives were lost in the Red River Valley, although one Minnesota man was killed by a large grain bin that blew over in Lake Lillian about 87 miles west of Minneapolis, and two people died in South Dakota due to the storm, according to wire reports.
The National Weather Service in Grand Forks described the flurry of storms as “a fast-moving and long-tracking Derecho/downburst/wind episode which tracked north-northeastward from northeastern Nebraska, through eastern South Dakota and southwestern Minnesota into far southeastern North Dakota and west-central Minnesota."
Derechos are relatively rare — but especially so in May.
“It’s pretty unusual (to happen) this early in the year,” said Vince Godon of the National Weather Service. “Usually, it’s more like a July/August event.”
Godon says derechos are more likely to occur in the Midwest when the corn fields are growing and transpiring moisture into the air, which helps contribute to the 90-and-above temperatures and dewpoints in the 70s.
So how did the derecho affect us? The weather service recently released this detailed report:
- Tornado 1, EF1 (weak), with peak winds of 100 mph near Charlesville and Elbow Lake, Minn. This twister began at 7:07 p.m. half a mile southeast of Charlesville, Minn., and ended three minutes and three miles later 13 miles west of Elbow Lake, Minn.
Several large ash and cottonwood tree limbs were broken down in shelterbelts and several power poles were damaged.
- Tornado 2, EF1 (weak), producing peak winds of 100 mph near Le Mars in Richland County, N.D. This twister began at 7:10 p.m. 1.5 miles southwest of Le Mars, then traveled 3 miles to end at northwest Le Mars three minutes later.
The storm broke tree limbs of ash and box elder trees in shelterbelts, cracked at least two wooden power poles and caused two other poles to lean.
- Tornado 3, EF2 (strong), producing peak winds of 115 mph near Tenney and Campbell, Minn. It began at 7:16 p.m. 1 mile southwest of Tenney in Minnesota’s Wilkin County and lasted nine minutes during its nine-mile journey, which ended 3 miles north of Campbell, Minn.
According to weather service records, “this tornado was best marked by the trail of at least 23 power poles which were cracked or completely snapped along its route.”
In addition, numerous trees were snapped and garage doors blown in at rural homesteads. The community of Campbell showed widespread tree damage, with numerous spruce trees uprooted and ash and cottonwoods snapped. Falling trees damaged numerous homes and communities throughout the community and large steel bins at the Campbell elevator complex were partially caved in.
- Tornado 4, EF1 (weak), producing peak winds of 100 mph, by Battle Lake, Minn. It began at 7:31 p.m. 2 miles southwest of Battle Lake, Minn., and ended just three minutes later 1.5 miles north/northeast of Battle Lake. This short, intense storm flipped a single-wide trailer; snapped or uprooted numerous spruce, poplar and ash trees, and blew metal roofing off a storage building.
- Tornado 5, EF1 (weak), producing peak winds of 85 mph over West Mason Lake. This waterspout was observed over West Mason Lake, near Clitherall, Minn., from 7:40 to 7:41 p.m. The winds it generated broke several large 6- to 10-inch diameter tree branches on the lake’s north shore.
- Tornado 6, EF2 (strong), producing peak winds of 115 mph near Verndale and Sebeka, Minn. The tornado was reported 1 mile southwest of Verndale in Wadena County at 7:53 p.m. It ended 18 minutes later after traveling 16 miles to 5.5 miles southeast of Sebeka.
This tornado snapped power poles while breaking and uprooting trees throughout a broad area. Falling trees also damaged numerous homes and vehicles throughout the communities of Verndale, Blue Grass and surrounding rural areas.
Numerous farm buildings, especially those which were open to the south, lost steel roofing and sidewall panels to the winds. Roofs were torn off turkey barns and other industrial buildings as well.