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International Maritime Meteorological Tape (IMMT-5) Format (deck 926) (by ESRL)

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Table 1. Field-by-field mapping between the International Maritime Meteorological Tape (IMMT-5) format (left columns) and the International Maritime Meteorological Archive (IMMA-1) format (right columns). Mappings of fields configurations between IMMT and IMMA are direct (no transformation) except as listed below this table for fields marked with an asterisk "*" (note: preliminary information, under development).
IMMT-5*IMMA-1
abbr
*it
yr
mo
dy
hr
lat
lon
*lat
*lon
*hi
vi
*h
vv
*n
*d
*wi
w
*at
at
*dpti
dpt
dpt
*slp
ww
w1
w2
*nh
*cl
*cm
*ch
*sst
sst
si
wmi
wp
wh
*sd
sp
sh
is
es
rs
os
op
id
c1
nu
qci
ix
ir
rrr
tr
*wbti
wbt
wbt
a
ppp
ds
vs
*sd2
sp2
sh2
*ic1
*ic2
*ic3
*ic4
*ic5
fm
immv
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi1
qi21
hdg
cog
sog
sll
*slhh
*rwd
rws
qi22
qi22
qi22
qi22
qi22
qi22
qi22
rh
rhi
awsi
imono

* Following is a list of exceptions, organized by IMMA field name, to a direct mapping (IMMT=IMMA) of individual input IMMT field configurations (on the left) to IMMA output configurations (on the right). Some outstanding questions in the transformation method are highlighted.

IT
"3"="0"
"4"="1"
"5"="2"
LAT
quadrant 3=negative LAT
quadrant 5=negative LAT
LON
quadrant 5=negative LON[+360.0]
quadrant 7=negative LON[+360.0]
HI
"0"="0"
"1"="1"
"2"="1"
"3"="0"
VI
"0"="0"
"1"="0"
"2"="1"
"3"="1"
H
"/"="A"
N
"/" and blank (assumed missing)=missing
D
"00"="361"
"99"="362"
tens=tens*10
WI
"0"="0"
"1"="1"
"3"="3"; related field action: knots=knots*0.51444444444444444444 for both W and RWS
"4"="4"; related field action: knots=knots*0.51444444444444444444 for both W and RWS
AT
sign 1=negative AT
DPTI
"0"="0"
"1"="0"; related field action: negative DPT
"2"="2"; related field action: negative DPT
"5"="1"
"6"="1"; related field action: negative DPT
"7"="3"; related field action: negative DPT
SLP
hundreds<500.0=hundreds+1000.0
NH
"/" and blank (assumed missing)=missing
CL CM CH
"/"="A"
SST
sign 1=negative SST
SD
"99"="38"
WBTI
"0"="0"
"1"="0"; related field action: negative WBT
"2"="2"; related field action: negative WBT
"5"="1"
"6"="1"; related field action: negative WBT
"7"="3"; related field action: negative WBT
SD2
"99"="38"
IC1 IC2 IC3 IC4 IC5
"/"="A"
SLHH
sign 1=negative SLHH
RWD
"000"="361"
"999"="362"

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