Significant Wind Levels
The beginning of section 6 may be identified in the
coded message by the indicator group 21212. This
section is used to report winds at "significant wind
levels." All observers on U.S. Navy ships, Marine
Corps, and naval upper-air observers operating outside
WMO Region IV report significant level winds in this
section, and need not report any information in the
PILOT reporting code. Synoptic stations and other land
or mobile land stations within WMO Region IV do not
include this group in the TEMP coded report. Instead,
the Fixed Regional Level Winds are reported using the
appropriate PILOT code message Parts B and D.
Data for each significant wind level is contained in
two groups of five-digit numbers, nnPPP and ddfff,
which are repeated for each level selected. The first
group for each level is used the same as in the significant
temperature levels: it contains the level identifier nn
and the pressure level PPP. The second group, ddfff, is
the wind direction and speed. Encoding is the same as in
part A of the code. Levels of missing wind data are
reported similarly to missing significant levels of
temperature and humidity.
System Status and Seawater Temperature
1-28
Section 7 (Table 1-9), 31313 srrarasasa 8GGgg
9snTwTwTw, contains information on the rawinsonde
system used for the observation, the actual launch time
of the instrument, and the seawater temperature. The
31313 is the section identifier.
In the second group, srrarasasa, the sr is the solar
and IR radiation correction, found from WMO Code
Table 3849. MRS systems use code figure 4, solar and
IR radiation corrected automatically by system. The
rara is the code for the rawinsonde system used and is
obtained from WMO Code Table 3685. The current
MRS system is reported by code 61 for the "Vaisala RS-
80 Marwin." The sasa is the tracking technique and
system status, from WMO Code Table 3872. Code 05 is
used with MRS equipment using VLF-Omega
frequencies. GPS equipped systems will use code
figure 08.
The actual UTC time of the radiosonde release is
entered in the fourth group following the 8 indicator. If
the radiosonde instrument is released at 1120Z, the
group would read 81120.
The seawater temperature group is only reported by
ships, and is deleted in reports from other stations. It is
in the fourth group, which begins with the indicator 9.
The sn, the sign of the temperature (0 for positive and 1
for negative) is followed by the water temperature
(TwTwTw) in tens, units and tenths of a degree Celsius.
Cloud Data
Section 8 (Table 1-9) reports cloud information in
one group following the 41414 indicator group. The
NhCLhCMCH is the cloud group. The Nh is the sum of
all the low-etage clouds present, or if no low-etage
clouds are present, the sum of all the mid-etage clouds
present, in oktas (WMO Code Table 2700), and h is the
coded height above the surface of the lowest cloud layer
(WMO Code Table 1600). The CL, CM, and CH
represent, respectively, the predominant type of low-,
mid-, and high-etage clouds from WMO Code Tables
0513, 0515, and 0509.
Regional Codes
Regional codes are added to the international code
following the regional code indicator groups. In WMO
Region IV, the required regional codes are specified in
the FMH-3. In Region IV, all regional data is reported
in “additional” data groups, commonly called the 101-
groups, following the 51515 Regional code indicator.
Other countries may use different regional codes
following any of the other regional code indicator
groups 52525, 53535, . . ., 59595, and national codes
61616, 62626, . . ., or 69696. Regional and national
codes for other countries are found in WMO
Publication 306, Manual On Codes, Volume II,
Regional Codes and National Coding Practices.
The 101 -groups are five-digit groups following the
format 101 AdfAdf. The AdfAdf indicates the type of
data being reported as listed in table 1-6. Actual data
may follow a "101-group" in additional code figure
groups. Only data pertaining to the sounding below the
100-hPa level is reported with 101-groups in Part B.
These groups can be used to report doubtful data,
corrected data, or early transmission data. If the
sounding terminates below the 100-hPa level, the
reason for termination is also entered in this section.
PART C - UPPER MANDATORY LEVELS
Part C of the TEMP codes contains reports for
mandatory levels above the 100-hPa level. The
mandatory levels reported in this section are the 70-hPa,
50-hPa, 30-hPa, 20-hPa, and 10-hPa levels. This
section uses the same format as Part A of the TEMP
code message, including identification data, mandatory
level data for the levels above 100 hPa, tropopause data
