Thomas tried to talk to the old man the Gladers found outside the city because?

Thomas approached the old man because he wanted to know if it was safe to enter the city.

“Sir? We really need your help!” He felt bad for shouting, worried the old man might take it the wrong way, but he had no choice. The wind was gusting stronger and stronger. “We need you to tell us if it’s safe to go inside the city! We can carry you there if you need help yourself. Sir? Sir!”