The balloon was damaged by the accumulation of snow this winter, despite efforts to minimize its impact.
The weight of the snow on the balloon was an estimated five to 10 tons.
In anticipation of even more snow, the manufacturer recommended that the balloon be deflated.
The damage cut short the life of the balloon, which was intended to fly for its final year in 2014.
This was actually the second Channel 6 ZooBalloon to fly at the Philadelphia Zoo. This type of balloon's life expectancy is about five to seven years.
The inaugural balloon lasted six years, and the current would have been flying for its seventh year this coming spring.
The Philadelphia Zoo and Channel 6 staff were preparing for farewell festivities and a final send-off celebration after Labor Day. However, due to these unexpected circumstances, the balloon will not take flight this year.
The Channel 6 ZooBalloon has been a part of Philadelphia since June 2002, when it was introduced as the only tethered helium balloon located in an American zoo.
Approximately 228,000 zoo guests have flown in the balloon since its first flight.