OFFICE NOTE 124
(Updated version of June 1976 edition)
NMC/NCEP FORMAT FOR SURFACE REPORTS
Original
NMC Automation Division Staff
June 1976
FINAL Revision
Dennis A. Keyser
NCEP Environmental Modeling Center
MARCH 2001
Revision Number 4 to NMC/NCEP Office Note Number 124.
The date of this revision is March 16, 2001 (03/16/2001).
This office note describes the format for
surface reports in the
NMC observational files. This revision
represents the final
update to NMC/NCEP Office Note Number
124. This format for
representing meteorological surface observational
data at NMC
(later NCEP) was discontinued in March
1997 when WMO FM 94-IX
Code Form: Binary Universal Format for
the Representation of
meteorological data (BUFR)
became operational at NCEP. WMO BUFR
remains the official observational data
format at NCEP. An
accurate version of this Office Note is
still necessary for
historical reference. This revision
incorporates corrections
and expansion of the table specifying
report type and additional
data code figures for certain meteorological
parameters which
were previously unspecified.
Revision Number 3 (dated 2/1996) had also
incorporated some
minor corrections and additions since
Revision 2 which had been
made necessary by the January 1, 1982
synoptic code change. The
specifics of this change are explained
in detail.
Information contained in the NMC observational
surface synoptic
reports consists of combinations from
the IBM EBCDIC character
set. A negative value is indicated
by a minus (-) sign located
in the leftmost position. A positive
value is unsigned.
A report is composed of two main parts:
(1) the report
identification group of fixed length (50
characters), and (2)
the bookkeeping and the observational
data of variable length.
Each report consists of 70 characters
or more.
The information contained in the report
identification group is
given in APPENDIX S.1.
The last parameter in this group
contains the total number of ten-character
words in the report
and thus provides the linkage from one
report to the next so
that several reports may be contained
in a block. The report
identification group is followed by the
category/counter and
observational data groups as needed.
The format of the
category/counter groups is described in
APPENDIX
S.1.
Observational data is formatted according
to the categories
described in APPENDIX
S.2. Where no data of a given category
exist, the category/counter group as well
as the data will be
absent from the report. The final
group in a report contains
the ten characters "END REPORT".
The number of characters in
each category of data is evenly divisible
by 10 and the
character "X" is used as fill if necessary.
Because of this
and the length of the groups, the number
of characters in a
report (including the "END REPORT") is
also evenly divisible by
10. Reports are formatted such that
the "END REPORT" signal is
found in the same block as the beginning
of that report.
Following are the modifications made necessary
by the
introduction of FM 12-VII and FM 13-VII
January 1, 1982:
(1) The code figures for iR
, iW , and iX are placed into
character
characters
25, 26 and 27 respectively of the report identification
group.
(2) The second character of past
weather W2, is located in the 36th
character
of category 51. (This location was previously
assigned
to the quality
mark of the dewpoint depression.) The exception is
when a manual
P,
H or C flag is assigned to the dewpoint
depression,
in which case this character is the quality mark of the
dewpoint
depression.
(3) Category 08
code figures 110-149 give section and group number
information.
For example, code figure 136 means the data are from
a 6-group
in section 3 of FM 2-VII or FM 13-VII.
(4) Section 5 of WMO code FM 12-VII
is stored in category 09. These
data are
indicated by a 5 in the first character of the first group
only.
The hourly (SA) data remarks section is stored in category
09 indicated
by a 1 in the first character of each group.
(5) Pressure level indicator 1 has
changed meaning from 1000 gpm to
1000 mb.
(Several of the old indicators are no longer used.)
(6) tR, the length
of time covered by the 6RRRtR group is located in
the 12th
character of category 52. (This location
was previously
assigned
to Rt, time precipitation began.)
(7) Period of swell waves in category
52 has changed from a code figure
to seconds.
(8) The unit of wave height in category
52 has changed from half-yard
to half-meter.
(9) The units of 24-hour pressure
change have been changed from a code
figure to
tenths of millibars. If the pressure change is less than
zero the
value stored is the absolute value (in tenths) plus 500.
(10) Certain reports are actually converted
hourlies (stored with block
station
identification and report type 511). The 37th character
of
the report
identification group indicates whether the report is a
converted
hourly or a regular synoptic report (1=hourly, 9=regular
synoptic).
(11) Hourly reports (stored with call letter
identification and report
type 512)
have experienced no changes due to the January 1, 1982
code change.
LIST
OF APPENDICES
Report
Identification
Category/Counter
Group
Formats
for the Categories of Data
Category
51 - Surface Data
Category
52 - Surface Data
Category
08 - Additional Data Groups
Category
09 - Plain Language Data
Table
SM.1 - Report Type
Table
SM.8a - Code Figures and Specifications
for Category 08
Table
SM.8a.1 - Definitions of Symbols Used in
Table SM.8a
Table
SM.8b - Indicator for Specification
Table
SM.8c - Indicator for Form
Table
SM.9 - Content of Plain Language Data
Table
SM.51 - Markers for Parameters
Sample Reports to Illustrate Formats
APPENDIX
S.1
______________________________________________________________________
Character|
|
|
Number(s)| Parameter
| Unit
| Remarks .
|
|
|
1 - 5 | Latitude *
| Hundredths of degree | Negative if in
|
|
| So. Hemisphere
|
|
|
6 - 10 | WEST longitude * | Hundredths
of degree | Values 00000 to
|
|
| 35999
|
|
|
11 - 16 | Station
| Alphanumeric | Left justified,
|
identification $|
| blank fill
|
|
|
17 - 20 | Observation time *| Hundredths of hour
| -----
|
| (UTC)
|
|
|
|
21 - 27 | Reserved
| See @ below |
-----
|
characters |
|
|
|
|
28 - 30 | Report type
| Character from | Always an
|
| Table SM.1
| integer
|
|
|
31 - 35 | Station
| Meter
| Negative if
|
elevation * |
| below sea
|
|
| level
|
|
|
36 | Synoptic format
| -----
| See % below
|
flag (land |
|
|
synoptic only) |
|
|
|
|
37 | See $ below
|
|
|
|
|
38 - 40 | Total length
| Number of
| -----
|
of report | ten-character
words|
|
|
|
.
* Whenever value is "missing" or not applicable,
all characters for the
parameter will contain "9".
@ For report types 511-562 (see Table
SM.1): Characters 21-24 hold receipt
time (hundredth of an hour,
missing is 9999; characters 25-27 hold flags
iR, iW,
iX.
For report types 571,573,574,576:
Characters 21-22 hold the number of
individual retrievals that
were used to produce this superob (missing or not
a superob get 99);
characters 23-26 hold the standard deviation of the
individual retrievals that
were used to produce this superob {units are 10
times that for datum in cat.
08 (see Tables SM.8a and SM.8a.1),
missing or
not a superob get 9999}.
% New = 1, ASOS = 2, AWOS = 3, automatic
other than ASOS or AWOS = 4,
manual = 9.
$ Either: converted hourly flag (hourly
= 1, regular = 9) or location flag for
ships.
_____________________________________________________________________
Character|
Number(s)|
Parameter
.
|
41 - 42 | Category code figure from
Appendix
S.2
|
43 - 45 | Number of ten-character
words in the report which
|
precedes the next category/counter group plus one. *
|
46 - 47 | Number of times data format
for current category is
|
repeated (i.e., the number of levels or entries)
|
48 - 50 | Total number of characters
in current category (fill
|
characters not counted)
|
.
* More simply stated, the relative position
in the report of the
next category/counter group.
APPENDIX
S.2
Whenever values are "missing", all
characters allowed
for that parameter will contain
"9", except for quality
marks which will always be as stated.
Category 51 -- Surface data (60 characters each entry)
_________________________________________________________________________________
No. of |
|
characters |
Parameter
| Unit
.
|
|
5 | Sea-level
pressure (see Note 1) | Tenth of millibar
|
|
5 | Station
pressure
| Tenth of millibar
|
|
3 | Wind
direction
| Degree
|
|
3 | Wind
speed
| Knot
|
|
4 | Air
temperature
| Tenth of degree C
|
|
3 | Dewpoint
depression
| Tenth of degree C
|
|
4 | Maximum
temperature
| Tenth of degree C
|
|
4 | Minimum
temperature
| Tenth of degree C
|
|
1 | Quality
mark for sea-level pressure | Character from Table SM.51
|
|
1 | Quality
mark for station pressure | Character from Table
SM.51
|
|
1 | Quality
mark for wind
| Character from Table SM.51
|
|
1 | Quality
mark for air temperature | Character from Table
SM.51
|
|
1 | Past
weather (W2) (see Note 2)
| WMO code table 4561
|
|
3 | Horizontal
visibility
| WMO code table 4300
|
|
3 | Present
weather (WW)
| WMO code table 4677
|
|
2 | Past
weather (W1)
| WMO code table 4561
|
|
2 | Fraction
of the celestial dome | WMO code table 2700
| covered by cloud (N)
|
|
|
2 | Fraction
of the celestial dome | WMO code table 2700
| covered by all the CL (or CM)
|
| clouds present (Nh)
|
|
|
2 | Clouds
of genera Sc, St, Cu, Cb (CL)|
WMO code table 0513
|
|
2 | Height
above the ground of the base | WMO code table 1600
| of the cloud (h)
|
|
|
2 | Clouds
of genera Ac, As, Ns (CM)
| WMO code table 0515
|
|
2 | Clouds
of genera Ci, Cc, Cs (CH)
| WMO code table 0509
|
|
1 | Characteristic
of pressure tendency | WMO code table 0200
| during the 3 hours preceding the |
| observation time (a) (see Note 3) |
|
|
3 | Amount
(magnitude) of the pressure | Tenth of millibar
| tendency (see Note 3)
|
|
|
.
Note 1 - Reference Category 51, sea-level pressure
(PPPPP), the following
information describes the method for accommodating the possible
values encoded in the 4PPPP group of FM 12-VII.
Characters Level Unit
PPPPP
Sea level
Tenth of millibar
21PPP
1000 mb
Geopotential meter
25PPP
500 mb
Geopotential meter
27PPP
700 mb
Geopotential meter
28PPP
850 mb
Geopotential meter
29PPP
Unknown
(as reported)
Note 2 - If character is P, H or C
then this parameter is the quality mark
for dewpoint depression. (See Table SM.51.)
Note 3 - When the characteristic of the pressure tendency
is 9 and the
amount of the pressure tendency is not 999, the tendency is a
24-hour pressure change in tenths of millibars unless less than
zero. In this case the stored value is the absolute value (in
tenths) of pressure tendency plus 500.
Category 52 -- Surface data (40 characters each entry)
_________________________________________________________________________________
No. of |
|
characters |
Parameter
| Unit
.
|
|
4 | Amount
of precipitation past 6 hours | Hundredth of an
inch
| (see Note 1)
|
3 | Total
depth of snow on ground
| Inch
| (see Note 2)
|
|
|
4 | Total
precipitation past 24 hours |
Hundredth of an inch
| (see Note 1)
|
|
|
1 | Duration
of precipitation observation | Number of 6-hour
|
| periods
|
|
2 | Period
of waves (see Note 3)
| Second
|
|
2 | Height
of waves
| Half meter
|
|
2 | Direction
from which swell waves are | WMO code table 0877
| moving
|
|
|
2 | Period
of swell waves
| Second
|
|
2 | Height
of swell waves
| Half meter
|
|
4 | Sea
surface temperature
| Tenth of degree C
|
|
2 | Special
phenomena, general
| See Note 4
|
|
2 | Special
phenomena, detailed
| See Note 4
|
|
1 | Ship's
course
| WMO code table 0700
|
|
2 | Ship's
average speed
| WMO code table 4451
|
|
7 | Water
equivalent of snow and/or ice | Hundredth
of an inch
|
|
.
Note 1 - Trace is output as 9998.
Note 2 - Trace is output as 998.
Note 3 - No estimate due to confused sea. Output
as 98.
Note 4 - Special phenomena, general, is missing (99)
only if special
phenomena, detailed, is missing (99).
Category 08 -- Additional data (10 characters each entry)
_________________________________________________________________________________
No. of |
|
characters |
Parameter
| Unit
.
|
|
5 | Data
given by specifications
|
| in Table SM.8a.1 (see Note 1)
| Variable
|
|
3 | Form
of additional data in
| Code figure from
| report (see Note 2)
| Table SM.8a
|
|
1 | Indicator
for data
| Character from Table
| specification
| SM.8b
|
|
1 | Indicator
for form of
| Character from Table
| additional data
| SM.8c
|
|
|
|
.
Note 1 - Value set to "missing" (99999) if not
applicable or transmitted as
missing.
Note 2 - Entries will be ordered as encountered in
report.
Category 09 -- Plain Language Data (12 characters each entry)
_________________________________________________________________________________
No. of |
|
characters |
Parameter
| Unit
.
|
|
1 | Indicator
of content of the
| Character from Table
| plain language
| SM.9
|
|
11 | Plain language
data
| Alphanumeric text
|
|
.
APPENDIX
S.3
* - No longer used.
& - Includes one or more of the following:
surface tag, ice
concentration,
ice age, ice edge, calculated surface type.
a = SSM/I ice age (0 = first year ice, 1 = multiyear ice).
CCC = Height above sea-level in hundreds of feet.
DDDD = The original data value
determined by the data type.
The data type is indicated in Table SM.8b.
For pressure, pressure in millibars multiplied by ten.
For latitude, latitude in degrees multiplied by one
hundred (negative if southern hemisphere).
For longitude, longitude in degrees west(?) multiplied by
one hundred.
For air temperature, air temperature in degrees Celsius
multiplied by ten.
For water temperature, water temperature in degrees Celsius
multiplied by ten.
For wind, wind represented by ddfff (where dd is direction
in degrees divided by 10 and rounded to the nearest 10
degrees, and fff is speed in knots).
e = SSM/I ice edge (0 = no edge present, 1 = edge present).
f = SSM/I
surface tag (0 = land, 1 = vegetation covered
land, 2 = near coast, 3 = multiyear ice, 4 = possible
ice, 5 = ocean, 6 = coast).
iii = Ice concentration in per cent.
LL = Level indicator;
99 means sea level, 97 means station
level (surface).
mmm = Soil moisture in millimeters.
NN = Relative humidity category indicator (01 through 13).
ppppp = Altimeter setting in tenths of millibars.
PPP = Pressure in whole millibars (last three digits).
RRR = Liquid water in inches times ten.
RRRR = Precipitation in inches times one-hundred.
ss = SSM/I calculated
surface type (1 = vegetation, 3 = ice,
5 = ocean, 6 = coast, 7 = flooded condition, 8 = dense
vegetation, 9 = dense agriculture crops, 10 = dry
arable soil, 11 = moist soil, 12 = semi-arid surface,
13 = desert, 14 = precipitation over vegetation,
15 = precipitation over soil, 16 = composite
vegetation-water, 17 = composite soil-water-wet soil;
18 = dry snow, 19 = wet snow, 20 = refrozen snow).
sss = Snow depth in millimeters.
ttt = Temperature in
degrees Celsius multiplied by ten (even
tenths digit indicates positive, odd tenths digit
indicates negative).
tttt = Time in hours (UTC)
multiplied by one hundred plus
minutes.
TTT = Temperature in degrees Kelvin.
TTTT = Temperature in degrees Kelvin multiplied by ten.
wwwww = Wind speed in meters per second multiplied by ten.
xxx = Minutes.
zzz = Height above sea-level
in meters multiplied by ten.
TABLE
SM.8b - INDICATOR FOR SPECIFICATION
________________________________________________________________________
Character |
Meaning
.
|
blank |
Not specified
P (see $) | Data type is pressure
L (see $) | Data type is latitude
G (see $) | Data type is longitude
T (see $) | Data type is air temperature
S (see $) | Data type is water temperature
W (see $) | Data type is wind
|
.
$ - Applies only to code figure 600.
TABLE SM.8c - INDICATOR FOR FORM
________________________________________________________________________
Character |
Meaning
.
|
blank |
Not specified
0 (see $) | Refers to good accuracy
1 (see $) | Refers to fair accuracy
2 (see $) | Refers to suspect accuracy
3 (see $) | Refers to poor accuracy
7 (see $) | Refers to out-of-bounds
value
|
.
4 digits
4 digits
transmitted output
.
0 (see *) XXXX
XXXX
1 (see *) XXX/
XXX9
2 (see *) XX/X
XX9X
3 (see *) XX//
XX99
4 (see *) X/XX
X9XX
5 (see *) X/X/
X9X9
6 (see *) X//X
X99X
7 (see *) X///
X999
8 (see *) /XXX
9XXX
9 (see *) /XX/
9XX9
A (see *) /X/X
9X9X
B (see *) /X//
9X99
C (see *) //XX
99XX
D (see *) //X/
99X9
E (see *) ///X
999X
F (see *) ////
9999
* - Applies only to code figures 110-149.
$ - Applies only to code figure 196
(non-superobs).
TABLE SM.9 - CONTENT OF PLAIN
LANGUAGE DATA
________________________________________________________________________
Character |
Content
.
|
1
| Remarks section from SA (hourly) report
2
| Section 5 (or other) from FM 12-VII or FM13-VII report
|
.
TABLE SM.51 - MARKERS FOR PARAMETERS
_______________________________________________________________________
Character| Parameter| Meaning
| Local BUFR
| |
| Table Value.
-- all surface
data types --
blank | Any
| Not specified
| 7
H
| Any | Monitor keep
| 0(see *)
P
| Any | Monitor purge
|14(see *)
A
| PMSL | Good agreement between PMSL & PSTN
| 1(PMSL/PSTN)
B
| PMSL | Disagreement between PMSL & PSTN
|13(PMSL/PSTN)
D
| PMSL | Fair agreement between PMSL & PSTN
| 5(PMSL/PSTN)
| | at high
elevations
|
-- land surface
data only --
C
| PMSL | Missing PSTN for which expected
| 9 (PMSL)
-- marine surface
data only --
A
| Wind | Wind measurement by anemometer
| 5
C
|PMSL,wind,| Corrected value, by O.P. Center |
4
|temp,tdep | manual q. control (eff: 3/15/89) |
D
| PSTN | Unreliable PMSL from a ship report |12(PMSL/PSTN)
| | (reject
list)
| (see $)
| |
| .
Note: Here, PMSL refers to mean sea-level
pressure and PSTN refers
to station pressure.
* Overrides any other BUFR table values
previously assigned.
$ Overrides any other BUFR table values
previously assigned to PMSL).
APPENDIX
S.4
Typical land station other than blocks 70-74
070930086701001 12001223191511000091901551012010600993699999
350023-08803399999999
20200360308080803101020050801502020
69901116 091137139 0END REPORT
Typical land stations from blocks 70-74
035400976072353 12001223392511003971901551012010601013209672
180010005007201390050A
0749999900999909999930050901602024
51047 058047************XXXXXXEND
REPORT
Typical hourly (SA) report
0422007253CEF 12001155999512000759902351012010601009899999
300010022701199999999
0400109903030602101010075201701040
0003999999999999999999999999999999999999080190101074491014
0
9023020241 20003 WET 1RWY
XXXXXXEND REPORT
Typical moving ship (without name)
0264022200SHIP 12001242444523000009901751012010601018099999
060011018504099999999
A 0989999908080506101020205201701040
9999999999990101999999019099990000099999END
REPORT