3-9. Standard Artillery Computer
Duration, in hours, of the valid period from I 8:
M e t e o r o l o g i c a l Message
code figure 9 indicates 12 hours.
The complete standard artillery computer meteo-
rological message consists of a number of groups in
Height of the Meterological Datum Plane above
symbolic form, containing an introduction and 27
mean sea level in decimeters. This plane is the
computer lines. It is not necessary to include all
horizontal surface where the zone heights of
the meteorological elements are measured on
lines in every message, only those lines from the
land, the Meteorological Datum Plane is nor-
Meteorological Datum Plane (MDP) to the com-
really located at the height of the station
puter lines required by the artillery units initiating
above Mean Sea Level. At sea the Metero-
Iogical Datum Plane is normally at mean
a. The normal standard artillery computer meteo-
Pressure at the Meteorolgical Datum Plane in
rological message contains four groups, in sym-
hundreds, tens, and units, of millibars. When
bolic form, METCMQ LaLaLaLoLoLo YYGoGoGO
the pressure is 1,000 millibars or more, the
hhhPdPdPd. Refer to c below for an explanation of
thousandths digit is omitted.
the symbolic code for the first communication line
Zone number corresponding to a Iine number in
in the computer message. When it is not necessary
the message. Refer to table B.
to send the second group for hemispheric latitude
Direction from which the mean vector wind is
or longitude location, a series of XXXXXX will
blowing. measured clockwise from geographic
replace the second group.
north and expressed in thousands, hundreds,
b. The body of the message contains meteoro-
and tens of roils. Encoded from 001 to 640,
logical information for use with meteorological
as 000 when windspreed is zero. For zone
No. 00, the value of the wind direction is
computers. The message is printed in pairs of eight-
measured at the Meteorological Datum Plane.
figure groups, example: ZnZndddFFF TTTTPPPP
Speed of the mean vector wind for the zone,
etc. . . . called lines.
expressed in hundreds, tens, and units of knots.
(1) Each line, except for 00, contains means
For zone No, oo, the value will be windspeed
direction and windspeed values including mean
measured at the Meteororlogical Datum Plane,
virtual temperature values for a specific zone layer
Mean virtual temperature for the zone given in
in the atmosphere also included is the barometric
hundreds, tens, and tenths of a degree Kelvin.
pressure at the midheight of the zone.
For zone No. 00, the value will be the tempera-
(2) Line number 00 contains the actual values
ture measured at the Meteorological Datum
for the Meteorological Datum Plane.
Air pressure in the middle of the zone given in
(3) Refer to table B for the zone number code
thousands, hundreds, tens, and units of mini
and the designated upper and lower standard height
bars. For zone No. 00, the value will be the
limits for each zone.
pressure measured at the meteorological
c. Symbolic codes and explanations are given
below. . . _
S _lic _
Table A Code for Octant of Globe
-- Greenwich longitude
0 to 90 \
90 to 180 \
180 to 90 E
90 to 0 E
0 to 90 \'
90 to 180 \'
180 to 90 E
90 to 0 E .
Used when the area of applicability iS not indi-
cated by Iatitude and longitude.