Definition
Altitudes in the atmosphere where the outside air temperature is warmer than 0°C (32°F), so any ice that forms on an aircraft will begin to melt and liquid water will not freeze on contact with the airframe.
Plain English
Heights at which the air is warm enough that ice melts instead of forming.
Context Anchor
Seen in instrument flying and icing discussions when deciding whether to climb, descend, or change route to get out of icing conditions.
Why Pilots Care
Helps pilots choose an altitude that reduces the chance of encountering structural icing.
Grounding Statement
Picture the airplane moving from a cold cloud layer into a warmer layer of air where ice has a chance to stop building and start melting.
Intuition Check
Above-freezing does not mean the whole route is warm or ice-free. It means a specific altitude layer is warmer than 32°F or 0°C.
Example Sentence 1
After picking up light rime ice in the climb, the pilot requested a descent to 4,000 feet, where forecast temperatures indicated above-freezing levels.
Example Sentence 2
The forecast showed above-freezing levels beginning at 7,000 feet, allowing the flight to avoid icing by cruising higher.