Notation	Name	Description	Status
0	High-resolution data sample		stable
1	Within 20 hPa of surface		stable
2	Pressure less than 10 hPa (i.e., 9, 8, 7, etc.) when no other reason applies		stable
3	Base pressure level for stability index		stable
4	Begin doubtful temperature, height data		stable
5	Begin missing data (all elements)		stable
6	Begin missing relative humidity data		stable
7	Begin missing temperature data		stable
8	Highest level reached before balloon descent because of icing or turbulence		stable
9	End doubtful temperature, height data		stable
10	End missing data (all elements)		stable
11	End missing relative humidity data		stable
12	End missing temperature data		stable
13	Zero degrees Celsius crossing(s) for RADAT		stable
14	Standard pressure level		stable
15	Operator-added level		stable
16	Operator-deleted level		stable
17	Balloon re-ascended beyond previous highest ascent level		stable
18	Significant relative humidity level		stable
19	Relative humidity level selection terminated		stable
20	Surface level		stable
21	Significant temperature level		stable
22	Mandatory temperature level		stable
23	Flight termination level		stable
24	Tropopause(s)		stable
25	Aircraft report		stable
26	Interpolated (generated) level		stable
27	Mandatory wind level		stable
28	Significant wind level		stable
29	Maximum wind level		stable
30	Incremental wind level (fixed regional)		stable
31	Incremental height level (generated)		stable
32	Wind termination level		stable
33	Pressure 100 to 110 hPa, when no other reason applies		stable
34	Freezing level base		stable
35	Freezing level top		stable
36	Flight level base		stable
37	Flight level top		stable
40	Significant thermodynamic level (inversion)		stable
41	Significant relative humidity level (according to NCDC criteria)		stable
42	Significant temperature level (according to NCDC)		stable
43	Begin missing wind data		stable
44	End missing wind data		stable
60	Level of 80-knot isotach above jet		stable
61	Level of 80-knot isotach below jet		stable
62	Other		stable
63	Missing value		stable