Instability which reached around 1000 J/kg of MLCAPE in an environment of weak deep-layer flow allowed thunderstorm cores to collapse and produce mainly damaging wind.
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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.
Instability which reached around 1000 J/kg of MLCAPE in an environment of weak deep-layer flow allowed thunderstorm cores to collapse and produce mainly damaging wind.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sioux Falls, SD wrote its last area forecast discussion before the first event at May 11, 11:07 AM CST, 2 hours 55 minutes earlier.
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</html>The Sioux Falls radar (KFSD), 74 km away, was scanning. The volume nearest the first event began at 20:00 UTC.
3 thunderstorm wind, 1 hail. Local standard time, as filed.
Thunderstorm winds tipped over a semi-truck near mile marker 36 on Interstate 29.
Thunderstorm winds snapped several large trees.
A flag pole was snapped off by thunderstorm winds, which also broke off several medium-sized branches in the yard.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2023Every state in 2023This day in weather historyWarnings in South Dakota, May 2023
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 2026-09-30. Each event’s entry at NCEI: 1101713, 1101712, 1101711, 1101714.