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Header of Code for Ship Weather Reports

 

 

Code format

B B X X CALLSIGN    
Y Y G G iw 9 9 La La La Qc Lo Lo Lo Lo  4 ix h V V 
N d d f f  1 sn T T T 2 sn Td Td Td 4 P P P P
5 a p p p 7 w w W1 W2 8 Nh CL CM CH 2 2 2 Ds Vs
0 ss Tw Tw Tw 2 Pw Pw Hw Hw 3 dw1 dw1 / / 4Pw1Pw1Hw1Hw1
6 Is Es Es Rs 8 sw Tb Tb Tb ICE ci Si bi Di zi

Meanings of each group

B B X X : Identifier of a ship weather report

CALLSIGN : Call sign of the VOS

Y Y G G iw :
Y Y - Day of month (UTC)
G G - Time of observation to nearest hour (UTC)
iw - Wind speed indicator
9 9 La La La :
9 9 - Indicator for sea station position groups
La La La - Latitude, degrees and tenths
Qc Lo Lo Lo Lo :
Qc - Quadrant of the globe
Lo Lo Lo Lo - Longitude, degrees and tenths
4 ix h V V :
4 - Indicates that precipitation group is omitted
ix - Indicator for weather group
h - Height of base of the lowest cloud
V V - Horizontal visibility
N d d f f :
N - Total cloud amount
d d - Direction of surface winds (true direction, in tens of degrees)
f f - Speed of surface winds
1 sn T T T :
1 - Group indicator for air temperature
sn - Sign of temperature (0 for 0 C or above, 1 for below 0 C)
T T T - Air temperature in whole degrees or and tenths
2 sn Td Td Td :
2 - Group indicator for dew-point temperature
sn - Sign of temperature (0 for 0 C or above, 1 for below 0 C)
Td Td Td - Temperature of dew-point in whole degrees or and tenths
4 P P P P :
4 - Group indicator for pressure
P P P P - Mean sea level pressure in hectopascal and tenths, thousands digit omitted
5 a p p p :
5 - Group indicator for pressure change
a - Characteristic changes in atmospheric pressure in last 3 hours
p p p - Change of pressure in tenths of hectopascal during last 3 hours
7 w w W1 W2 :
7 - Group indicator for weather
w w - Present weather
W1 W2 - Past weather during the preceding 6 hours
8 Nh CL CM CH :
8 - Group indicator for clouds
Nh - Total amount of low clouds (or medium clouds, if no low clouds)
CL - Type of low clouds: Cu, Cb, Sc, St
CM - Type of medium clouds: Ac, As, Ns
CH - Type of high clouds: Ci, Cs, Cc
2 2 2 Ds Vs :
2 2 2 - Section indicator for maritime data
Ds - Ship's course made good during the past 3 hours
Vs - Ship's average speed during the past 3 hours
0 ss Tw Tw Tw :
0 - Group indicator for sea surface temperature
ss - Sign and type of measurement of sea surface temperature
Tw Tw Tw - Sea surface temperature in whole degrees and tenths
2 Pw Pw Hw Hw :
2 - Group indicator for wind waves
Pw Pw - Period of wind waves in seconds
Hw Hw - Height of wind waves in units of half metre
3 dw1 dw1 / / :
3 - Group indicator for swell directions
dw1 dw1 - Direction in tens of degree from which the predominant swell is coming
4 Pw1 Pw1 Hw1 Hw1 :
4 - Group indicator for period and height of the predominant swell
Pw1 Pw1 - Period of the first (predominant) swell in seconds
Hw1 Hw1 - Height of the first (predominant) swell in units of half metre
6 Is Es Es Rs :
6 - Group indicator for ice accretion
Is - Type of ice accretion
EsEs - Thickness of ice in cm
Rs - Rate of ice accretion
8 sw Tb Tb Tb :
8 - Group indicator for wet bulb temperature
sw - Sign and type of wet bulb temperature
Tb Tb Tb - Wet bulb temperature in whole degrees and tenths
ICE : Indicator, ice group follows
ci Si bi Di zi :
ci - Concentration or arrangement of sea ice
Si - State of development
bi - Ice of land origin
Di - Bearing of principal ice edge
zi - Ice situation and trend over preceding 3 hours
Last revision date: <11 Apr 2018>