Military TAF Codes: The 5-Group and 6-Group Tables
A military TAF reads as an ordinary TAF until the trailer at the end. There it adds three groups a civil forecast never carries, plus remarks about the forecasting service itself. The two numeric tables below are AFMAN 15-124 Tables 1.5 and 1.7, read by the wxdecoder parser exactly as the manual writes them.
How the numeric groups are built
Both hazard groups use the same six-digit frame, and only the leading digit differs.
Digit 1 is the marker: 5 for turbulence, 6 for icing. Digit 2 is the intensity and type. Digits 3 to 5 are the base of the layer in hundreds of feet. Digit 6 is the thickness in thousands of feet.
So 620105 splits as 6, 2, 010, 5: the icing group, light rime icing in cloud, based at 1000 feet, 5000 feet thick. The layer runs 1000 to 6000.
The two fields use different units, and mixing them up is the most common error with either group. The base is hundreds. The thickness is thousands.
Turbulence: the 5-group
AFMAN 15-124 Table 1.7. The digits have a pattern: 2 to 5 are moderate and 6 to 9 are severe, odd numbers are frequent, and the second pair of each block is in cloud.
| Code | What it means |
|---|---|
0 |
no turbulence |
1 |
light turbulence |
2 |
occasional moderate turbulence in clear air |
3 |
frequent moderate turbulence in clear air |
4 |
occasional moderate turbulence in cloud |
5 |
frequent moderate turbulence in cloud |
6 |
occasional severe turbulence in clear air |
7 |
frequent severe turbulence in clear air |
8 |
occasional severe turbulence in cloud |
9 |
frequent severe turbulence in cloud |
X |
extreme turbulence |
Icing: the 6-group
AFMAN 15-124 Table 1.5. These run in blocks of three: 1 to 3 light, 4 to 6 moderate, 7 to 9 severe. Inside each block the order is mixed, then rime in cloud, then clear in precipitation.
| Code | What it means |
|---|---|
0 |
trace icing |
1 |
light mixed icing |
2 |
light rime icing in cloud |
3 |
light clear icing in precipitation |
4 |
moderate mixed icing |
5 |
moderate rime icing in cloud |
6 |
moderate clear icing in precipitation |
7 |
severe mixed icing |
8 |
severe rime icing in cloud |
9 |
severe clear icing in precipitation |
The altimeter group
Written out rather than coded, and easy to read once you know the parts.
| Code | What it means |
|---|---|
QNH2992INS |
altimeter setting 29.92 inches of mercury |
QNH |
names the setting type: the one that reads field elevation on the ground |
INS |
marks the unit as inches rather than hectopascals |
Service remarks
These describe the forecasting service rather than the weather, and they change how much the rest of the forecast is worth. The first one reads backwards at a glance.
| Code | What it means |
|---|---|
AMD NOT SKED |
amendments are not scheduled: nobody is on duty to update this forecast |
LAST NO AMDS AFT |
the final forecast for this airfield, not amended after the time given |
LIMITED METWATCH |
reduced forecaster coverage between the hours given |
AUTOMATED SENSOR METWATCH |
sensors only, with no forecaster on duty at all |
AMD |
this forecast was amended at the time that follows |
COR |
this forecast was corrected at the time that follows |
Frequently asked questions
What does 520005 mean?
The leading 5 marks the turbulence group. The 2 is occasional moderate turbulence in clear air. The 000 is a base at the surface, and the final 5 is a thickness of 5000 feet.
Do civilian TAFs have icing and turbulence groups?
No. A civil TAF carries neither. Those hazards reach civil pilots through AIRMET Zulu, AIRMET Tango and SIGMETs, which cover areas of airspace rather than one aerodrome.
Does AMD NOT SKED mean the forecast was amended?
The opposite. It means amendments are not scheduled at this airfield, so nobody will update the forecast if conditions change. It is a warning that the forecast is unwatched.
Is there a conflict in the AFMAN turbulence table?
A small one. The manual worked example at paragraph 1.3.3.1 narrates code 4 as light to moderate in cloud, while Table 1.7 says moderate. The table is the normative text, so that is what our decoder reports.