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Severe Thunderstorms in the Upper Midwest; Excessive Heat in the Central U.S.

Severe thunderstorms, capable of severe wind (locally exceeding hurricane force), very large hail, flash flooding and a few tornadoes, are possible late this afternoon into tonight across portions of the of the Upper Midwest into the southern Great Lakes. Excessive heat covers much of the central third of the country and is expected to persist into the weekend over the south-central states. Read More >

 

#11 Berthoud, Colorado Tornado 

June 4th, 2015 Berthoud, Colorado

 

On the evening of June 4th, 2015 a rare EF3 tornado, with estimated wind speeds up to 140 mph, tracked almost due west along the Boulder, Larimer county line.  The tornado was a quarter mile wide, at times, and had a path length of 6 miles.  This is the strongest tornado on record, that has affected Boulder and Larimer counties, since official ratings began in 1950.  28 homes were damaged with three being destroyed.  Fortunately, there were only a few minor injuries and no deaths.

 

Tornado track and intensity based on NWS Storm Survey

 

EF scale: The Enhanced Fujita scale classifies tornadoes into the following categories:

EF0...Weak......65 to 85 MPH
EF1...Weak......86 to 110 MPH
EF2...Strong....111 to 135 MPH
EF3...Strong...136 to 165 MPH
EF4...Violent...166 to 200 MPH
EF5...Violent...>200 MPH

Video of Tornado courtesy of Cory Reppenhagen

 

Reflectivity Loop at 0.5 Degrees

 

Storm Relative Velocity Loop at 0.5 Degrees

 

Damage pictures near the Boulder/Larimer county line