0 0 ISOLATED CLOUD FRAGMENTS OF CLOUDS
1 1 CONTINUOUS CLOUD
2 2 BROKEN CLOUD - SMALL BREAKS
3 3 BROKEN CLOUD - LARGE BREAKS
4 4 CONTINUOUS CLOUD
5 5 BROKEN CLOUD - SMALL BREAKS
6 6 BROKEN CLOUD - LARGE BREAKS
7 7 CONTINUOUS OR ALMOST CONTINUOUS WAVES WITH TOWERING CLOUDS ABOVE THE TOP OF THE LAYER
8 8 GROUPS OF WAVES WITH TOWERING CLOUDS ABOVE THE TOP OF THE LAYER
9 9 TWO OR MORE LAYERS AT DIFFERENT LEVELS
15 15 MISSING VALUE
