Weather Underground Forecast for Tuesday, September 11, 2012. There will only be one significant storm in the country on Tuesday. A cold front will begin the day stretched from the Southwest through the Dakotas before moving eastward into the Central Plains and Upper Midwest by the end of the day. There will not be a tremendous amount of moisture associated with this front, but rain and thunderstorms will form from the Four Corners through the Dakotas. The heaviest of this precipitation will fall in Utah and Colorado. Elsewhere, a stationary front will remain very close to the southern tip of Florida. This front could produce scattered showers and thunderstorms mainly south of Lake Okeechobee. To the north, an expansive high pressure system will move eastward to along the eastern seaboard. This system will continue to provide widespread dry conditions from the eastern Plains to the East Coast. Warm air will stream northward into the Southern and Central Plains, keeping afternoon temperatures in the 90s and 100s. Much cooler conditions are expected in the Northwest and Intermountain West as Pacific air streams into the region. The Northeast will rise into the 70s, while the Southeast will see temperatures in the 80s and 90s. The Plains will rise into the 90s and some 100s, while the Northwest will see temperatures in the 70s. Temperatures in the Lower 48 states Monday have ranged from a morning low of 28 degrees at Lakeview, Ore. to a high of 122 degrees at Cross City, Fla.