Weather may ground the iconic balloons of the Macy's Thanksgiving Day Parade. A cold front is expected to move into the New York area this week, bringing with it high winds that could force authorities to stop balloons from flying. The city doesn't allow the balloons to lift off if there are sustained winds higher than 23 miles an hour or gusts over 34 miles an hour. Current forecasts put winds just around that limit, but authorities will likely make the call on Thanksgiving morning.