I would not recommend it. Many used to run a cooling fan on their NiCD or NiMH packs while charging/discharging but sudden extreme temp changes aren't good.
The pack will actually perform better while it is warm [not HOT] off the charger. Anything over 125-130 degrees F and your charger is probably going past cutoff and overcharging them.

Charging at a lower amperage will help the heat issue somewhat