MINNEAPOLIS (AP) -- A storm system pushing through the upper Midwest produced reports of weak tornadoes in rural areas northwest of the Twin Cities Saturday afternoon.

The National Weather Service says a tornado touched down near a barn east of Becker in Sherburne County, knocking down several oak trees. Another tornado was reported to have touched down briefly in the vicinity of Big Lake, also in Sherburne County.

Other areas report downed trees and hail in thunderstorms that also produced heavy downpours.

A tornado watch in effect until 10 p.m. covers 25 counties in Minnesota and six in Wisconsin.

The watch covers southeastern Minnesota and northwestern Wisconsin.