Hi,

the WMO 306 Manual on Codes (2001) says that after a sunshine group in
the regional part of a SYNOP there can be groups with radiation
information if available. Those groups can start with 0..6 for the
different radiation types (0 = positive net rad., 1 = negative net
rad., ... 5 = upward long-wave rad., 6 = short-wave rad.).

But how can they be distinguished from another "regular" 5xxxx or
6xxxx (precipitation) group? E.g. in this SYNOP from yesterday:

AAXX 13031 10430 26520 /1601 10158 20141 39900 40086 58007 87/// 333
55300 69907 83/30 84/42 87/47

is "69907" precipitation (I think it is) or short-wave radiation?

Thanks for any help.

On 15 Jun, 09:17, wrote:
Hi,

the WMO 306 Manual on Codes (2001) says that after a sunshine group in
the regional part of a SYNOP there can be groups with radiation
information if available. Those groups can start with 0..6 for the
different radiation types (0 = positive net rad., 1 = negative net
rad., ... 5 = upward long-wave rad., 6 = short-wave rad.).

But how can they be distinguished from another "regular" 5xxxx or
6xxxx (precipitation) group? E.g. in this SYNOP from yesterday:

AAXX 13031 10430 26520 /1601 10158 20141 39900 40086 58007 87/// 333
55300 69907 83/30 84/42 87/47

is "69907" precipitation (I think it is) or short-wave radiation?

Thanks for any help.

I think the groups in (e) to (h) below have to be included each time
if radiation data are to follow. Your 69907 would be rainfall, not
radiation. It would be helpful to have Part B, to see regional
practice for the countries if interest.

FM 12 SYNOP, FM 13 SHIP, FM 14 SYNOP MOBIL
-
12.4.7.1.2 When the group 5j1j2j3j4 is used, one or more of the
following symbolic expressions shall
be adopted:
-
(a) 5EEEiE to report the daily amount of either evaporation or
evapotranspiration;
(b) 54g0sndT to report temperature change data in period covered by
W1W2;
(c) 55SSS to report the daily hours of sunshine;
(d) 553SS to report the duration of sunshine in the past hour;
(e) 55407 to indicate that the supplementary group 4FFFF, which
follows immediately,
is used to report net short-wave radiation during the previous hour,
in kJ m-2;
(f) 55408 to indicate that the supplementary group 4FFFF, which
follows immediately,
is used to report direct solar radiation during the previous hour, in
kJ m-2;
(g) 55507 to indicate that the supplementary group 5F24F24F24F24,
which follows
immediately, is used to report net short-wave radiation during the
preceding
24 hours, in J cm-2;
(h) 55508 to indicate that the supplementary group 5F24F24F24F24,
which follows
immediately, is used to report direct solar radiation during the
preceding
24 hours, in J cm-2;

Above extracted from this URL: http://www.knmi.nl/%7Emeulenvd/wmo/m...l-I-1PartA.pdf

John

wrote:

On a depressing note, does anyone know when the synop code will cease to
be, as I was under the impression that it's days were numbered and
BUFR/GRIP coding (all '0's and '1's) was going to take over.

--
Keith (Southend)
http://www.southendweather.net
e-mail: kreh at southendweather dot net

On 15 Jun., 20:49, wrote:
I think the groups in (e) to (h) below have to be included each time
if radiation data are to follow.
....
Hi John,
thanks for the info. The ambiguous part I mean is related to

(c) 55SSS to report the daily hours of sunshine;
(d) 553SS to report the duration of sunshine in the past hour;

In section 12.4.7.4.3 it says:
"When the group 5j1j2j3j4 has the form 553SS, the supplementary
group(s) j5FFFF may take one or more of the following forms:
j5 = 0 FFFF = positive net radiation during the previous hour, in kJ m-
2;
j5 = 1 FFFF = negative net radiation during the previous hour, in kJ m-
2;
j5 = 2 FFFF = global solar radiation during the previous hour, in kJ m-
2;
j5 = 3 FFFF = diffused solar radiation during the previous hour, in kJ
m-2;
j5 = 4 FFFF = downward long-wave radiation during the previous hour,
in kJ m-2;
j5 = 5 FFFF = upward long-wave radiation during the previous hour, in
kJ m-2;
j5 = 6 FFFF = short-wave radiation during the previous hour, in kJ m-
2."

To me (I'm not a native English speaker) it sounds like there can be 1
to 7 groups after 553SS, starting with 0 to 6. In 12.4.7.4.4, they
mention similar groups to follow 55SSS. If a radiation group starting
with 6 may follow, and also the precipitation group starting with 6,
how can the two cases be distinguished? 554xx and 555xx seem to be
used for just two other kinds of radiation; I could find no relation
to 55SSS and 553SS. Am I missing something here?

t would be helpful to have Part B, to see regional practice for the countries if interest.

Part B for Region VI (Europe) says only:
"These groups" (in section 3) "shall be used in accordance with
Regulation 12.4.7 of Volume I.1 of the Manual on Codes." and at what
time those groups should be included. Some national parts also just
mention the period for which it is valid and the reporting times.

I got help off list as response to posting. As far as I have
understood:

For the supplementary radiation groups 5xxxx (those that can follow
55SSS and 553SS) it is assumed that the value cannot be bigger than
5299 (in whatever unit). As after the 55SSS group there can follow
only 553xx (or bigger) main groups, all other smaller 5xxxx groups
must be supplementary radiation groups.

From all 6xxxx groups of section 3 only the last can be precipitation
and only if the indicator in section 1 says so (values 0 and 2); all
other 6xxxx must then be supplementary radiation groups.

Thanks!