Toph and Fire.

In the final hours of ATLA, Sokka, Suki, and Toph were just finished taking over a war blimp from the Fire Nation. As they were planning on how to take down the fleet, Phoenix King Ozai is burning the ground along with the other Fire Benders. As the fire was blazing, Toph makes the comment, "Wow. That's a lot of fire." How on earth did she know there was fire every where? I'm sure there is an explanation, but she was in the air, away from it, and blind. Help!