The Holmes, ND tornado was rated as an EF4, with peak winds estimated to 185 mph.  This tornado made its initial touchdown roughly 1 mile north of Mayville, ND around 349 pm, and produced a near continuous damage path through rural north-central Traill county into rural south-central Grand Forks county before lifting about 10 miles west of Thompson, ND around 410 pm.  The damage path was nearly 17 miles long and reached a maximum width of 150 yards at times.  Damage was most extreme at a farmstead near Highway 15, where a home was completely swept from its foundation and destroyed.

A pronounced debris ball was seen in radar reflectivity imagery (shown below), similar to the Northwood EF4 tornado in August of 2007.  This debris ball showed up just north of the KMVX WSR 88D, and became a very strong signature around the time EF4 damage was inflicted. 

   Holmes EF4 

Holmes, ND EF4 tornado track (click for larger image).

 
     

 

Base Reflectivity from 347 pm CDT - 433 pm CDT

347 pm CDT

352 pm CDT

357 pm CDT

401 pm CDT

406 pm CDT

410 pm CDT

415 pm CDT

420 pm CDT

424 pm CDT

429 pm CDT

433 pm CDT

       

 

  Debris Ball from 347 pm CDT -  410 pm CDT

347 pm CDT

353 pm CDT

358 pm CDT

347 pm CDT

403 pm CDT

410 pm CDT

       

 

Base Velocity from 347 pm CDT - 443 pm CDT

347 pm CDT

352 pm CDT

357 pm CDT

401 pm CDT

406 pm CDT

411 pm CDT

415 pm CDT

420 pm CDT

424 pm CDT

429 pm CDT

434 pm CDT

438 pm CDT

443 pm CDT

   

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