Tornado watch canceled

6:45 p.m. Update

SIOUX FALLS, S.D. - The tornado watch has also been canceled for the area.

5:08 p.m. Update

SIOUX FALLS, S.D. - A severe thunderstorm warning has been canceled for O'Brien County in northwest Iowa.

According to the National Weather Service, the storm has moved out of the area.

4:55 p.m. Update

SIOUX FALLS, S.D. - A severe thunderstorm warning has been issued for O'Brien County in northwest Iowa, to expire at 5:15 p.m.

At 4:47 p.m. National Weather Service Meteorologists were tracking a severe thunderstorm capable of producing quarter-size hail. This storm was located near Larrabee, or 24 miles northwest of Storm Lake, and moving northeast at 30 miles per hour.

The thunderstorm will be near Sutherland around 4:55 p.m. and Royal around 5:15 p.m.

Severe thunderstorms produce damaging wind in excess of 60 miles per hour, destructive hail, deadly lightning and very heavy rain. People are advised to move to an interior room on the lowest floor of a building. Heavy rains flood roads quickly, so do not drive into areas where water covers the road.

The tornado watch remains in effect.

Tornado watch issued for southwest Minnesota, northwest Iowa

2:45 p.m. Update

SIOUX FALLS, S.D. - The National Weather Service has issued a tornado watch, set to end at 9 p.m. today, for counties in Minnesota, including Cottonwood, Jackson, Murray, Nobles, Pipestone and Rock, and for counties in Iowa, including Dickinson, O'Brien, Osceola and Lyon.

Hail, tornado-producing storms expected

11:40 a.m. Thursday

NORMAN, Okla. - The National Weather Service expects significant and severe thunderstorms today and tonight over most of Iowa, central and southern Minnesota, as well as eastern South Dakota.

Large hail, damaging winds and a few tornadoes are expected to occur over the upper Mississippi valley, into parts of the mid-Missouri valley. Severe storms are also possible across the northern plains and upper Great Lakes.

A powerful upper-level storm system will move eastward today across the northern plains, while an associated surface low pressure center and trailing cold front shift eastward across the Dakotas and Nebraska into Minnesota and Iowa. A warm and humid air mass present ahead of this storm system will fuel severe thunderstorm development this afternoon along the cold front initially over the eastern Dakotas and eastern Nebraska, with storms subsequently developing east into Minnesota, Iowa and Wisconsin through tonight.

The warm and humid conditions, in conjunction with strong jet stream winds, will favor the development of intense, severe storms, including supercells with the thread for large hail, possibly strong tornados, and damaging winds.

With time, the storms may organize into a large complex, with the potential for more widespread damaging winds spreading east across parts of Minnesota and Iowa into western Wisconsin tonight.

State and local emergency managers are monitoring this developing situation. Those in the threatened area are urged to review severe weather safety rules and listen to the radio, television and weather radio for possible watches, warnings and statements later today.