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Table C5

Reference Time designator A2
(when T1   =   Q, X, or Y)

Instructions for the proper application of the reference time designator

1. The designator specified in this table should be used to the greatest extent possible to indicate the reference time of data contained within the text of the bulletin.

2. When the table does not contain a suitable designator for the reference time, an alphabetic designator which is not assigned in the table should be introduced and the WMO secretariat notified.

Data Type
Data Type
A Analysis (00 hour) N 39 hours forecast
B 3 hours forecast O 42 hours forecast
C 6 hours forecast P 45 hours forecast
D 9 hours forecasts Q 48 hours forecast
E 12 hours forecast R 54 hours forecast [48+6]
F 15 hours forecast S 66 hours forecast [+12]
G 18 hours forecast T 78 hours forecast
H 21 hours forecast U 90 hours forecast
I 24 hours forecast V 102 days forecast
J 27 hours forecast W 114 days forecast
K 30 hours forecast X 126 days forecast
L 33 hours forecast Y 138 days forecast
M 36 hours forecast Z 150 days forecast

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     Page last Modified: 23 October, 2013 1:40 PM