CHICAGO, Dec. 9 (Xinhua) -- Hundreds of flights were delayed and cancelled at several airports in Chicago due to a snow storm Wednesday that hit some states in mid-west of the United States, transportation officials in Chicago said.

A man adjusts the chute on a snowblower as he cleans up snow in Waukesha, Wisconsin Dec. 9, 2009. Much of the Midwest is forecast to have blizzard conditions and more snow fall, local media reported on Wednesday.(Xinhua/Reuters Photo) Photo Gallery>>>

    According to weather service observers, in great Chicago area, the biggest 24-hour snow totals were 8.5 inches in the northwestern areas, about 7 inches in the northern area.

    The official snow reading at Chicago's O'Hare International Airport this morning was 2.8 inches. But the airport in the northern city of Rockford, about 130 kilometers north of Chicago, had 11.4 inches of snow by this evening.

    Illinois state transportation officials were concentrating their snow-removal and ice-melting efforts in the northern areas which harder hit than areas in the south.

    By 8 p.m., windchills already had dipped into the single digits throughout the Chicago area, with windchills hitting 6 degrees below zero. Drivers are urged to watch out for patches of ice on roads, bridges and ramps as evening falls.

    In the city of Chicago, flooding and high standing water were reported on some city streets, and salt trucks were sent out to keep those intersections from freezing.

    Chicago's Snow Command was coordinating with the Chicago Transit Authority to make sure that the snow didn't drastically slow bus and train service. City crews will be available to salt bus terminals, turnarounds and garages.

    According to reports reaching here, a mixture of heavy snow, strong winds and freezing rain pounded the state of Wisconsin, causing widespread power outages, hundreds of school closings and treacherous travel.

    The University of Wisconsin in Madison was closed after it was blanketed by a foot and a half of snow. All state offices were shut down, and the U.S. National Weather Service issued a blizzard warning for 47 counties in the state through this evening.

    The Wisconsin State Patrol said as many as a dozen semi-trailer trucks became stuck on Interstate ramps near Madison. Patrol communications officials said the heavy snow made the ramps impassible and measures have been taken to clear the roads.