>> flights have to get in and out. they're very dedicated but they're dealing with very cold weather. >> reporter: the real life ice box also creating a laundry list of problems on the tarmac. refueling equipment freezing. vehicles not starting. all making the backlog even worse. the arctic cold for the aircraft, not that bad, you say. >> right. aircraft are used to high altitude and temperatures are cold. it is more on the ground that you see the impact. >> reporter: with the mercury slowly inching upward, already signs of a thaw. those in long lines at tampa international finally heard this -- >> if you want to check in, the lines are not long. >> reporter: on the east coast after suspending all flights for some 17 hours, jetblue now back and running. the beginning of a much-needed defrost and return to normal appear alex perez, abc news, milwaukee. >> and it is going to be another challenging morning with subzero windchills in many places. and nonstop snow near the great lakes.