| Code/Flag Figure |
Description |
Status |
|
0
|
Quasi-stationary front at the surface
|
Operational
|
|
1
|
Quasi-stationary front above the surface
|
Operational
|
|
2
|
Warm front at the surface
|
Operational
|
|
3
|
Warm front above the surface
|
Operational
|
|
4
|
Cold front at the surface
|
Operational
|
|
5
|
Cold front above the surface
|
Operational
|
|
6
|
Occlusion
|
Operational
|
|
7
|
Instability line
|
Operational
|
|
8
|
Intertropical front
|
Operational
|
|
9
|
Convergence line
|
Operational
|
|
10
|
Jet stream
|
Operational
|
|
11
|
Cloud clear
|
Operational
|
|
12
|
Cloud
|
Operational
|
|
13
|
Turbulence
|
Operational
|
|
14
|
Storm
|
Operational
|
|
15
|
Airframe icing
|
Operational
|
|
16
|
Phenomenon
|
Operational
|
|
17
|
Volcano
|
Operational
|
|
18
|
Atmospherics
|
Operational
|
|
19
|
Reserved
|
Operational
|
|
20
|
Special clouds
|
Operational
|
|
21
|
Thunderstorm
|
Operational
|
|
22
|
Tropical cyclone
|
Operational
|
|
23
|
Mountain wave
|
Operational
|
|
24
|
Duststorm
|
Operational
|
|
25
|
Sandstorm
|
Operational
|
|
26-62
|
Reserved
|
Operational
|
|
63
|
Missing value
|
Operational
|