Unacceptably strong winds at the Complex 41 launch pad forces a scrub in the launch of Lockheed Martin's Atlas 5 rocket and the New Horizons spacecraft. Liftoff was targeted for the end of the day's window but the winds exceeded the 33-knot limit, prompting an abort of the countdown at T-minus 2 minutes, 34 seconds.
Source: NASA TV (1 min 41 sec QuickTime 6 file)
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