Bullettin is issued daily and consists of 3-hourly averaged forecast fields for 3 and a half days from
15/01/2021
at 00:00 GMT to
18/01/2021
at 12:00 GMT.
Forecast fields are centred at 1.5hr,
4.5hr, 7.5hr, 10.5hr, 13:5hr, 16.5hr, 19.5hr and 22.5hr
GMT each day.
(e.g. forecast fields for day
15/01/2021
at 4.5hr
is the mean from 3 hrs to 6 hrs GMT on
15/01/2021
)