Last week's storms produced 9 tornadoes, including one 10 football fields wide
HILLSBORO, N.D.—Meteorologists have confirmed storms from last week produced seven tornadoes in the Red River Valley, including one in Traill County that tracked 23 miles and reached the width of 10 football fields.
Severe weather brought hail, damaging winds and, to some counties, tornadoes on July 11, downing power lines, breaking trees and causing power outages. The National Weather Service counted nine confirmed reports of tornadoes for that evening in east North Dakota and west Minnesota, according to a weather summary on the service's website. No injuries or deaths were reported.
All but two twisters touched down in the Red River Valley, the largest being a multi-vortex tornado that touched down 8 miles east of Hatton, N.D., or 40 miles southwest of Grand Forks. The vortex traveled 23 miles, reached speeds of 135 mph and at its maximum width was 1,200 yards, according to the weather service. Those measurements gave it a ranking of EF-2 on the Enhanced Fujita Scale, which meant the damage it caused was considerable, according to the weather service.
The tornado eventually let up about 4 miles northeast of Hillsboro, about 40 miles south of Grand Forks, but not before snapping trees, structural damage and downdraft winds of 80 to 100 mph, according to meteorologists.
The length of a football field including end zones is 120 yards.
There were two other EF-2 tornadoes in the Valley, meteorologists concluded. One that touched down about 4 miles southeast of Hillsboro tracked 11 miles and hit speeds of 130 mph. It was measured at 600 yards wide at one point and crossed into Minnesota before retreating into the skies near Halstad, Minn., or 30 miles north of Fargo.
The third EF-2 tornado traveled 13 miles, starting 3½ miles north of Borup, Minn., or about 35 miles northeast of Fargo, the report stated. It hit speeds of 135 mph and was measured at 500 yards wide.
"It collapsed at least one shed, snapped numerous trees and tossed dozens of large 2,000-pound round hay bales more than a half mile across a sugar beet field," meteorologists said in their report. "It also snapped at least a half dozen wooden power poles along its path."
Two tornadoes also touched down in Grand Forks County, meteorologists confirmed. The first was a EF-1 twister about 4 miles northwest of Northwood, N.D., or 40 miles southwest of Grand Forks, that traveled 4½ miles with a maximum width of 150 yards. The maximum speed was 90 mph. The second hit the ground about 4 miles northwest of Manvel, N.D., hit speeds of 75 mph, also was 150 yards wide and traveled for 1.7 miles, earning it an EF-0 ranking. That was roughly 15 miles northwest of Grand Forks.
Other EF-1 tornadoes included one touching down 6 miles southwest of Alvarado, Minn., in Polk County, according to the report. That one lasted 10 miles, hit speeds of 95 mph and was only 250 mph. Another appeared 5 miles northwest of Adams, N.D., or about 70 miles northwest of Grand Forks, hitting 105 mph, tracking 7 miles and measuring in at 150 yards wide.
There were two tornadoes confirmed outside the Valley. One was spotted near Clyde, N.D., or about 50 miles north of Devils Lake.The other came down near Rocklake, N.D., or about 60 miles north of Devils Lake. Both were ranked EF-0 tornadoes, only traveled half a mile and hit speeds of 70 mph.