A large-scale bow echo fueled by MLCAPE around 2500 J/kg and 30 to 35 knots of deep-layer shear developed across central South Dakota, before weakening toward the James River where shear profiles were much weaker around 20 knots. Storms produced damaging wind gusts prior to weakening.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FSD wrote it up.
A large-scale bow echo fueled by MLCAPE around 2500 J/kg and 30 to 35 knots of deep-layer shear developed across central South Dakota, before weakening toward the James River where shear profiles were much weaker around 20 knots. Storms produced damaging wind gusts prior to weakening.
The Aberdeen radar (KABR), 205 km away, was scanning. The volume nearest the first event began at 01:20 UTC.
5 thunderstorm wind. Local standard time, as filed.
A brief burst of wind caused damage to tree branches before settling back to 30 to 40 mph.
Part of a roof was blow off a lean-to. Photos of damage provided by the Emergency Manager. Property damage amounts are rough estimates.
Part of a roof was blown off a hoop barn, with numerous tree branches blown off toward the northeast. Photographs provided by the county Emergency Manager. Property damage amounts are rough estimates.
A machine shed walk-in door was ripped from its hinges and thrown 40 to 50 feet. The door was latched at the time of the storm with all other doors closed. Several tree branches from 3 to 4 inches in diameter also downed by the strong winds. Property damage amounts are rough estimates.
An anchored play set and gazebo were destroyed. Several large limbs were also downed by the strong winds. Minor damage occurred to house skirting and siding. Property damage amounts are rough estimates. Crop damage is an estimate from insured losses. Information provided by the United States Department of Agriculture.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2020Every state in 2020This day in weather historyWarnings in South Dakota, July 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 910520, 910518, 910519, 910522, 910521.