Page 16 - AFMAN 15-111, 12 MAR 2019

16 AFMAN15-111 12 MARCH 2019

3.10.1. When cloud height and visibility values are less than or equal to halfway between two
reportable values, report the lower value; otherwise, report the next higher value. Example:
cloud heights of 2,549 feet (ft) and 2,550 ft are reported as 2,500 ft and visibility values of 5
1/4 SM (8250 m) and 5 1/2 SM (8500 m) are reported as 5 SM (8000 m).

3.10.2. When computations of pressure values require that a number be rounded to comply
with standards of reportable values, the number is always rounded down to the next reportable
value. Example: A station pressure reading of 29.249 is rounded down to 29.245 and 29.244
is rounded down to 29.240. An ALSTG of 29.249 and 29.244 are both truncated to 29.24.
3.10.3. ALSTGs provided for international aviation purposes and reported in hPa are always
rounded down and reported as whole numbers. Example: 1009.9 hPa and 1009.1 hPa are both
truncated to 1009 hPa.
3.11. Dissemination. Most WFs/Dets use an ADS as the primary local and longline
dissemination system. During periods when the ADS is unavailable use AF Weather-Web Service
(AFW-WEBS), the OWS or another WF/Det to disseminate observations longline. Figure 3.2
contains example METAR/SPECI augmented observations.
3.11.1. Pressure altitude (PA) and density altitude (DA) are disseminated locally. When
required, disseminate PA (e.g., PA +130) or DA (e.g., DA +3680) following the last element
or remark in the observation, with the exception of runway condition remarks which are
reported last.

3.11.2. Corrections (COR) to Transmitted Data. Disseminate CORs in the same manner as the
observation being corrected as soon as possible whenever an error is detected in a transmitted
report. However, if the erroneous data has been corrected or superseded by a later report (with
the same or more complete dissemination), do not transmit the corrected observation.
Transmitted corrections will consist of the entire corrected observation. Use the original date
and time of the observation as the date and time in the COR'd observation. See Attachment 3.
(T-0).