Altitude MSL of base of high cloud layer. Returns 0 if no high cloud layer is active. Measured in feet. Read-only.
Note: All weather variables report the weather in the aircraft's current location. This weather information only reflects the weather defined by the weather commands if the aircraft is in the area defined by the Weather and Weather_Char commands.
Example
IF CLOUD_HIGH_BASE > 30000 THEN
PRINT "You should be clear of clouds below FL290."
ENDIF