You have antifreeze leaking from somewhere that is hitting something hot and turning it to steam.When you turn on the AC the fan is pulling it into the vents. Keep track of your engine collant levels and if they are lowering then there is your problem!!
A 1998 Jeep Cherokee has disc brakes in the front.
The 2014 Jeep Cherokee has 53.8 in. of front hip room.
The 2001 Jeep Cherokee has 37.7 in. of front head room.
The 2014 Jeep Cherokee has 41.1 in. of front leg room.
The 2001 Jeep Cherokee has 54.1 in. of front shoulder room.
The 2001 Jeep Cherokee has 41.4 in. of front leg room.
The 2014 Jeep Cherokee has 57.6 in. of front shoulder room.
The 2014 Jeep Cherokee has 39.4 in. of front head room.
The 2001 Jeep Cherokee has 54.8 in. of front hip room.
The front track of the 2014 Jeep Cherokee is 5 ft. 2 in. (62 in.).
Cold air blowing out of the heater is a sure sign of low coolant. Antifreeze running out of the front of the motor _could_ be a bad water pump. The two go together like ham & eggs.
The 2002 Jeep Grand-Cherokee has 56.5 in. of front hip room.