Page 50 - AFMAN 15-111, 12 MAR 2019
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50 AFMAN15-111 12 MARCH 2019
10.5.2. When multiple phenomena are appended to an intensity qualifier, the qualifier is
denoting the intensity of the total precipitation.
10.5.3. Present weather groups will be encoded in the following order and precedence: (T-1).
10.5.3.1. Tornadic Activity - Tornado, Funnel Cloud, then Waterspout.
10.5.3.2. Thunderstorms - on station or in the vicinity, with or without associated
precipitation.
10.5.3.3. Precipitation in order of decreasing predominance.
10.5.3.4. Obscurations and/or other phenomena in order of decreasing predominance.
10.6. Descriptors. Descriptors serve to further describe certain weather phenomena to provide
additional specificity on the observed conditions. Additional information for each descriptor (with
encoded form in parenthesis) is provided below and in Table 10.1
10.6.1. Shallow (MI): Only used to describe fog that has very little vertical extent (<6ft) where
visibility is reduced in the horizontal but can be easily seen through when looking in the
vertical.
10.6.2. Partial (PR): Only used to describe fog where visibility is reduced in the horizontal
and covers part of the celestial dome but does not constitute a vertical visibility sky condition
(i.e. a surface-based obscuration covering less than 8 oktas of the sky).
10.6.3. Patches (BC): Only used to describe small areas of fog with little vertical extent (~6-
20ft).
10.6.4. Low Drifting (DR): Only used to describe dust, sand, or snow that is being raised by
the wind to a height of less than 6ft and is not obstructing visibility.
10.6.5. Blowing (BL): Only used to describe dust, sand, snow, or spray that is being raised by
the wind to a height above 6ft and is obstructing visibility.
10.6.6. Shower(s) (SH): Only used to describe showery-type (cumuliform) precipitation;
characterized by a rapid start, stop, and/or change in intensity. When encoded as in the vicinity,
the type of precipitation is not included (i.e., VCSH not VCSHRA).
10.6.7. Thunderstorm (TS): May be encoded by itself or with an associated precipitation
type(s); RA, SN, PL, GS, GR, and UP are the authorized types of precipitation that may be
appended to TS. When it is determined that a thunderstorm is within 5-10NM, it may be
encoded as VCTS. If thunder is heard and the distance cannot be reliably determined, TS will
be encoded as on station. (T-2). See manual observing procedures for additional guidance on
determining the use of TS in the body of the observation.
10.6.8. Freezing (FZ): Only encoded with fog when the temperature is below freezing or with
rain or drizzle when super-cooled liquid droplets are freezing on contact with surface objects
and coating them with a glaze of ice.
10.7. Weather Phenomena. Weather phenomena are divided into the three categories of
precipitation, obscurations, and other.
