The McPherson/Brown County Tornado
June 23rd, 2002
The National Weather Service, in conjunction with Local and County law enforcement, along with Emergency Management, have completed an aerial and ground survey of the tornado damage that occurred on Sunday, June 23, 2002 across McPherson and Brown counties in Northeast South Dakota.
Four separate tornado tracks have been confirmed, with two additional satellite touchdowns identified...from the Supercell thunderstorm which tracked across eastern McPherson and northern Brown counties.
The initial, brief touchdown occurred in McPherson county at 7:20 pm approximately 5 miles north and 4 miles east of Leola. This has been rated as an F0 tornado.
The second tornado touched down in McPherson county at 7:34 pm, a little over 3 miles north and 8 miles east of Leola. This tornado moved generally to the east, and crossed into Brown county at 7:40 pm about 3 miles north of state highway 10, continuing southeast for another 2 miles before dissipating. This tornado has been rated as an F1 due to damage observed in McPherson county. The first satellite tornado was associated with this tornado for part of the track across Brown county. Tornado number 2 appears very large from photographic and video evidence, but since very little ground damage can be confirmed, the rating is F1. The total track length of this F1 tornado was 5 miles.
Tornado three developed in Brown county at 7:53 pm 1 mile north of state highway 10 and 5 miles west of U.S. Highway 281. It moved east, producing F2 damage to power transmission equipment (hi-res picture/lo-res picture), then F1 damage as it crossed Highway 281 (hi-res picture 1 & 2/lo-res picture 1 & 2). Continuing east, the tornado moved just south of Barnard South Dakota. F3 damage was documented 1/2 mile south of Barnard (hi-res picture 1,2,3,4,5/lo-res picture 1,2,3,4,5). The tornado continued moving east for another 3 miles producing F2 damage (hi-res picture 1,2,3,4/lo-res picture 1,2,3,4) before dissipating. The total path length of this F3 tornado was 9 miles.
The fourth major tornado began at 8:24 pm 2 miles south and 4 miles east of Barnard, producing F0 damage at that point. This tornado moved northeasterly, strengthening to an F2 1 mile north and 1 mile east, where the second satellite tornado was observed, then increasing to an F3 2 miles west of Sand Lake National Wildlife Refuge Headquarters (hi-res picture 1,2,3,4,5,6/lo-res picture 1,2,3,4,5,6). The tornado then turned north, producing F2 damage. (hi-res picture 1,2,3,4/lo-res picture 1,2,3,4). Continuing to move north, the tornado crossed state highway 10 where it produced F4 damage (hi-res picture 1,2,3,4,5,6,7/lo-res picture 1,2,3,4,5,6,7). The tornado then turned briefly to the west, then to the south, dissipating over highway 10. The total path length of this F4 tornado was 10 miles.
This is the first F4 tornado ever recorded in Brown County, SD. F4 tornados are classified as devastating...with wind speeds ranging from 207 to 260 mph. The Fujita scale ranges from F0 to F5 in strength. For more information concerning tornadoes and the Fujita scale, see the Storm Prediction Center web page.