Early morning thunderstorms leave downed trees, power outages
By ERIK SANDIN – Stillwater Gazette
Parts of the St. Croix Valley spent this morning cleaning up from a fast moving line of powerful thunderstorms that roared through the region during the early morning hours.
The storms brought heavy rain and wind gusts up to 70 mph to parts of the Valley. The strongest cells struck the southern metro area, including Cottage Grove in southern Washington County, according to National Weather Service meteorologist Jim Taggart.
The high winds downed trees and power lines, leaving thousands in the metro area and Valley without power on a day when Taggart said temperatures are expected to rise to the low to middle 90s and combined with dew points in the middle 60s, will make it feel like 100.
Washington County Administrator Molly O’Rourke briefed the Board of Commissioners this morning on storm damage in the county.
"We’ve got lots of power outages," she said. "We’ve also had many traffic signals out."
"Straight line winds are what happened here," added county Emergency Services Director Deb Paige. "We did sound the sirens in the southern part of the county."
With another round of thunderstorms forecast tonight and into Wednesday, a large part of eastern Minnesota, including the metro area and the Valley, are under a flash flood watch until early Thursday.
Paige said there is concern about additional rain causing a sudden rise on the lower St. Croix River.
"They are concerned with the St. Croix," she said about the NWS. "Right now, we’re fairly low on the St. Croix."
Taggart said this morning’s storms moved through the Valley around 4:30 to 5 a.m. after developing west of the metro area.
"The storms developed in western Minnesota about two to three o’clock in the Redwood Falls area," he said. "The most severe part of the storms went through the southern part of the Twin Cities."
Taggart said the storms brought wind gusts of 60 to 70 mph and .75- to 1-inch rainfalls. He added that one NWS observer in Stillwater reported 1.5 inches of rain.
"We were lucky. It was moving at a pretty good clip," Taggart said about the line of storms, adding that the system moved through the metro area around 60 to 70 mph.
A National Weather Service statement said the storms are forming along and north of a stationary front over extreme southern Minnesota. The statement adds that any storms developing today could produce heavy rain with rates of more than one inch per hour.
The statement said any more heavy rains could "exacerbate flooding problems from not only rainfall received this morning but also rainfall received over the past several days."
Taggart, however, said because of the hot, humid forecast today, any thunderstorms in the metro area would probably not occur until tonight.
"Right now, it looks like any thunderstorm activity is north of the Twin Cities," he said. "During the evening is when it looks like storms might develop (in the metro)."
Taggart said as the front in southern Minnesota moves north, it would shift winds in the area and clear out lingering clouds.
"As the boundary moves northward, our winds will switch from the east to the south and things will clear out," he said.
The NWS said more storms are possible for early Wednesday as low pressure moving out of South Dakota drags a cold front across the region.
"It looks like late tonight or tomorrow, the front will come through and things will calm down for us." Taggart said.