By this point in the instruction, you probably know the importance of very cold cloud-top temperatures. They are associated with active weather. Play the IR imagery loop. After observing the systems identified on the imagery, step through each frame to locate the system with the coldest cloud-top temperatures.

Which system has the coldest cloud-top temperatures?

1. Opal
   
2. System 1
   
3. System 2
   
4. Tropical System