A confirmed tornado northwest of Watertown late July 27 caused “significant damage” to a farmstead, a National Weather Service meteorologist told the Argus Leader.
The damage was still being assessed, so the tornado had not yet been assigned a rating as of the morning of July 28, said Kelly Serr, a meteorologist with the National Weather Service in Aberdeen.
“We have to look at the damage to be able to assign the wind speed,” Serr said. “Radar tells us a lot – it told us there was rotation there – but it can’t tell us the actual wind speed of the tornado itself.”
There were reports of large hail on the south side of Watertown and farther to the south, Serr said, and also reports of between 3 to 5 inches of rain in Hamlin County, where some secondary roads were flooded.
Multiple images and videos of the tornado were shared online as it tore across fields near Watertown.
Storm topples power lines in Watertown
Watertown Fire Rescue responded to multiple reports of downed power lines during the July 27 storm, a news release says. Here are the details:
Shortly before 7 p.m., crews responded to 11th Street and 1st Avenue NE and found that a tree had fallen onto power lines, dropping the lines on several vehicles parked nearby. The responders confirmed that the power lines were no longer energized.
About 7:05 p.m., crews responded to a report of two power poles in the roadway at 1528 17th St. NE, north of the Premier Softball complex. Both poles had snapped off, causing a large power line to make contact with a nearby residence. The power line made a burn mark on the home and damaged a gas line outside, so crews turned off the gas and made sure no fires had started inside.
Shortly before 8 p.m., crews responded to a report of another downed power line in the 1700 block of 4th Avenue SW, where they found a tree had fallen on a power line, knocking it to the ground.
More severe weather forecast for July 28
Another round of severe thunderstorms is expected to move through the region in the late afternoon July 28, with heavy rain and hurricane-force winds possible, the weather service says.
The main concern will be wind gusts of 70 mph or more, though large hail and a few tornadoes are also possible. The storms could become a derecho as they drift over eastern South Dakota, according to the National Weather Service’s Weather Prediction Center.
The area most at risk for high winds was north of Interstate 90, including Aberdeen, Brookings, Huron and Watertown. The weather service said it “highly advised” securing any items that might easily blow away before the storms arrive.
Severe thunderstorms are expected to hit eastern South Dakota in the late afternoon July 28, potentially bringing hurricane-force winds to the region.
This article originally appeared on Sioux Falls Argus Leader: NWS still assessing damage after July 27 tornado near Watertown