| Code/Flag Figure |
Description |
Status |
|
1
|
Surface
|
Operational
|
|
2
|
Standard level
|
Operational
|
|
3
|
Tropopause level
|
Operational
|
|
4
|
Maximum wind level
|
Operational
|
|
5
|
Significant temperature level
|
Operational
|
|
6
|
Significant humidity level
|
Operational
|
|
7
|
Significant wind level
|
Operational
|
|
8
|
Beginning of missing temperature data
|
Operational
|
|
9
|
End of missing temperature data
|
Operational
|
|
10
|
Beginning of missing humidity data
|
Operational
|
|
11
|
End of missing humidity data
|
Operational
|
|
12
|
Beginning of missing wind data
|
Operational
|
|
13
|
End of missing wind data
|
Operational
|
|
14
|
Top of wind sounding
|
Operational
|
|
15
|
Level determined by regional decision
|
Operational
|
|
16
|
Freezing level
|
Operational
|
|
17
|
Pressure level originally indicated by height as the vertical coordinate
|
Operational
|
|
All 18
|
Missing value
|
Operational
|