Destructive ‘drill bit’ tornado carves deadly path in Minnesota

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Destructive ‘drill bit’ tornado carves deadly path in Minnesota

Storms chasers captured shocking close-up footage of the twister, which flattened farmsteads.

Intense thunderstorms spawned multiple tornadoes in west central Minnesota on Wednesday, flattening farmhouses and claiming at least one life. One slow-moving, ferocious twister gave storm chasers the unusual opportunity to position themselves perilously close and photograph arguably some of the most remarkable tornado footage ever recorded.

The storms came after a particularly quiet tornado season on the Plains, with the fewest number of significant tornadoes in recorded history.

A rain-free storm and high storm base allowed for the tornado to be seen far and wide, and a number of chasers tempted fate with daring up-close encounters that revealed the tornado’s true force. Meteorologists and storm chasers referred to it as a “drill bit” tornado, extreme velocities concentrated in an unusually narrow vortex at times barely 10 feet across.

[‘More will die’: The ethics of up-close tornado chasing]

Three farmsteads were reportedly damaged or destroyed by the day’s strongest tornado in the vicinity of Dalton and Ashby, about 170 miles northwest of Minneapolis.

The Otter Tail County Sheriff’s Office confirmed via social media that two residents were transferred to hospitals in unknown condition, with one fatality. County officials searched the damage swath over a six- to nine-mile stretch east of Dalton.

A lone storm with no competition



A radar shot of Wednesday’s tornadic storm in Minnesota reveals the secret to its fury: With no other storms for hundreds of miles, it could tap into the atmosphere’s full power with no competition. (GR2 Analyst)

A lone rotating supercell thunderstorm displayed remarkable beauty amid an exhibition of deadly power in western Minnesota shortly after 5 p.m. on Wednesday, and the storm was firing about three hours northwest of Minneapolis near the Otter Tail-Grant County line.

Oddly enough, it was the day’s second tornado warning for areas affected, coming 13 hours after a line of predawn storms prompted concerns over rotation. Although no tornado occurred, 83 mph winds struck Fergus Falls, Minn., toppling up to 10 campers at Otter Tail.

** 83 mph wind gust at the Fergus Falls Airport around 435 am *** the airport is about 1-2 miles west of town. Take shelter now in Fergus Falls #mnwx

— NWS Grand Forks (@NWSGrandForks) July 8, 2020

The atmosphere “reloaded” over the course of the day, and the National Weather Service Storm Prediction Center issued a severe thunderstorm watch at 4:10 p.m. A few instances of wind or hail were expected, with only a “low” risk of “a tornado or two.”

The risk for tornadoes was not mentioned in the afternoon forecast discussion penned by the National Weather Service in Grand Forks, N.D. Meteorologists there did highlight the chance of winds to 60 mph or hail to quarter size.

Defying forecasts, a spinning thunderstorm quickly developed before 5 p.m., acquiring enough rotation to spur a tornado warning at 5:08 p.m. A tornado was confirmed at 5:11 p.m., potentially lasting through 5:45 p.m. as its visual confirmation was relayed to the National Weather Service.

A second cell produced a brief tornado near Vining, well to the east of Dalton, around 6:30 p.m.

Storms later merged into a line, with primarily a wind and hail threat.

A picturesque portrait of power

The highly picturesque tornado — hailed as the “tornado of the year” by veteran storm chasers — stood ominous, in stark contrast to a seemingly tranquil background illuminated by breaks of blue sky and sunshine. Tornadoes generally form in the rain-free “updraft” region on the southwest side of a severe thunderstorm, though it’s rare to have a tornado this readily visible and photogenic.

Michael Marz, a Minneapolis-based storm chaser, recorded mind-boggling video of the tornado — perhaps only a few yards wide at that point — scouring the ground in a field, its peripheral winds toppling trees outside the main condensation funnel. Note that the videos in embedded tweets from Marz may contain strong language.

The intense tornado was remarkably slow moving as well, luring storm chasers to precariously close distances.

Some debate has echoed through the storm chaser community in the past surrounding just how close “too close” is, and some have expressed concern that such close pursuit sets a dangerous precedent.

Marz also recorded a shot of the tornado shredding trees and tossing them hundreds of feet into the air. It bears striking resemblance in some ways to the Wynnewood, Okla., tornado of May 9, 2016.

However, the limited number of structures in the path of Wednesday’s tornado may make it difficult for the National Weather Service to reliably assess. Damage to trees can only be assigned a rating up to low-end EF4 strength in the most extreme of circumstances, but the rating assigned for snapped hardwood trees typically errs closer to 110 mph — in the high-end EF1 range.

The Enhanced Fujita scale rates tornadoes based on observed damage — not visual observations or radar signatures. And unless objects or structures are hit at the tornado’s peak strength, it’s impossible to assign a rating commensurate with a tornado’s maximum fury.

Social media video, as well as the ground scouring and motions of the funnel contained therein, suggest that Wednesday’s twister was a significant (EF2 or greater) tornado, and may have contained winds in the EF3 range.

July: The new May?

July has already proved a more rewarding month for many storm chasers than May or June — typically reliably active months that feature jaw-dropping storms. According to the Storm Prediction Center, “May 2020 saw a significant severe weather and tornado drought,” and that tornado deficient continued into June as “another record breaking [slow] month.”

[Opinion: storm chasing is overcrowded. That makes it even more dangerous.]

On July 1, a stunning — and surprise — tornado sneaked through Seward County, Kan. The next day, an elephant trunk tornado danced near Hemingford, Neb., while an Independence Day tornado in Saskatchewan left U.S. storm chasers envious of their Canadian counterparts.

More tornadoes spun up in parts of South Dakota and Wyoming on Monday, including one that downed a swath of trees in the Black Hills National Forest.

Additional severe thunderstorms are possible over parts of the Northern Plains, especially central South Dakota, on Thursday. More storms appear likely Monday.

TORNADO DAMAGE in Black Hills National Forest, SD surveyed by drone with massive wedge moving through the Timber Gulch region on July 6. Evidence of convergent zones and swirls in the downed trees from subvortices locally excited by topography. Tracked on @RadarOmega_WX app pic.twitter.com/PbeGJqLeAS

— Reed Timmer (@ReedTimmerAccu) July 8, 2020

Additional photos and videos from Minnesota

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