Page 40 - AFMAN 15-111, 12 MAR 2019

40 AFMAN15-111 12 MARCH 2019

8.4.6. Software limitations in some automated sensors only support visibility reporting
increments of 1/4SM (from 0 to 1 3/4 SM) and 1/2 SM (from 2 to 3 SM). Leadership will
locally document procedures to ensure supplementation during controlled airfield hours for
observed values that are beyond the capability of the software to report when required to meet
published landing and/or circling minimum visibility values. (T-3).

Table 8.1. Visibility - Reportable Values.

Visibility - Reportable Values in SM | Meters
0 0000 1/2 0800 1 1/2 2400 3 4800
1/16 0100 5/8 1000 1 5/8 2600 4 6000
M1/8 M0200 3/4 1200 1 3/4 2800 5 8000
1/8 0200 7/8 1400 1 7/8 3000 6 9000
3/16 0300 1 1600 2 3200 7 9999
1/4 0400 1 1/8 1800 2 1/4 3600 8 9999
5/16 0500 1 1/4 2000 2 1/2 4000 9 9999
3/8 0600 1 3/8 2200 2 3/4 4400 10 9999
Notes:
1. Values are reported in 1SM increments from 10 to 15SM and 5SM increments above 15SM.
2. All values greater than 6SM are reported as “9999” when reporting in meters.
3. Some values may not be supported by FMQ-19, FMQ-23 or Automated Surface Obeserving
System (ASOS) software.
4. M1/8 (M0200) is an automated report for visibility less than 1/8SM (0200m).
5. MAJCOMs may direct the use of 3000m and 5000m in place of 3200m and 4800m
(OCONUS).

8.5. Manual Observing Methods.
8.5.1. Prevailing visibility is observed with un-aided vision (i.e. no binoculars or night vision
goggles) from a designated point of observation that permits the weather technician to evaluate
the horizon circle at the surface.
8.5.1.1. The point of observation should be as free from obstructions as possible to permit
the maximum view of the horizon circle. Where obstructions exist, move to as many
locations as necessary and practical within the period of observation to view as much of
the horizon as possible.

8.5.1.2. At locations that necessitate deviation, visibility may be determined from a
designated point of observation that is elevated but is always be reported as the surface
visibility and will be documented in the FLIP (e.g. “SFC VIS determined at ATC tower”
or “Visibility obs at 50ft AGL”). (T-2).
8.5.2. Evaluate visibility as frequently as practical using all available visibility markers to
determine the greatest distance that can be seen in all directions around the horizon circle.

8.5.2.1. If a marker has sharp outlines and little blurring of color, the visibility is much
greater than the distance to that marker.