1 flash flood, as filed by the National Weather Service.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 Aberdeen radar (KABR), 207 km away, was scanning. The volume nearest the first event began at 02:58 UTC.
1 flash flood. Local standard time, as filed.
Heavy rains of 2 to 5 inches fell in Lyman county during the late evening hours which caused flash flooding on Medicine Creek. The KOA Campgrounds near Kennebec were flooded including the main facility. Several roads were also flooded and damaged along Medicine Creek.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 1999Every state in 1999This day in weather historyWarnings in South Dakota, May 1999
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 2026-09-24. Each event’s entry at NCEI: 5698218.