Dear All,

Am I right in thinking that the gust reported in SYNOPs every 3 hours
(06, 09, 12Z etc.) is the peak gust during the past 3 hours, and the
gusts at the other times (04, 05, 07, 08Z etc.) are just the strongest
gust in the last hour?

Is this adhered to in every country that reports SYNOPs?

Many thanks !
Richard

Richard Dixon wrote:
*********
(After) 333 Group - Special / Climatological Data

9SSss -- Supplementary information

90710 10=past hour (proceeds UK gust reports), Ireland does not report
this.

910XX 10=gust in past 10 minutes. 91155=55 knots (UK when indicator is '4')
911XX 11=gust in past hour 91199 00125 = a gust of 125 knots.
912XX Highest mean wind speed in the time indicated by group 904XX.
e.g. 90410 = last hour's obs, 91234 = highest mean wind 34 knots or m/s.
(912XX not used for UK reports.)

********
000 Group - Identification and Location (Beginning)

iw -- Wind type indicator

0 m/s (estimated)
1 m/s (from anemometer)
3 knots (estimated)
4 * knots (from anemometer)


or

iu -- Wind type indicator

0 m/s (land stations abd ships with certified instruments)
1 knots (land stations and ships with certified instruments)
2 m/s (ships with uncertified instruments)
3 knots (ships with uncertified instruments)

This indicator "iu" is used only in the following codes:

FM63 - BATHY (Report of bathythermal observation)
FM64 - TESAC (Temperature, salinity and current report from a sea station).


e.g.
Lille(52m) - France
AAXX 19094 (* the 4 indicates Knots from anemometer)
07015 22962 02404 10122 20042 30161 40218 56007
333 60007 90710 91110 93100
555 60005=

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