Freezing level contour lines at specific altitudes.
Multiple freezing level boundaries.
OptionalrangeOverall freezing level range description (e.g. "RANGING FROM SFC-110 ACRS AREA" or "040-060 ACRS AREA").
OptionalrangeUpper bound of the freezing level range in feet.
OptionalrangeLower bound of the freezing level range in feet. Undefined when the lower bound is at the surface.
Freezing level information from an AIRMET Zulu bulletin. Describes where the freezing level is located across the advisory area, including altitude ranges, contour lines, and multiple freezing level boundaries.