On 07/05/11 11:04, Martin Rowley wrote:
07/0558Z - 07/0630Z (latter time determined by the 10-minute rule):
weak, low audio-frequency rumbles fairly near, with short period of
moderate/heavy rain around the start of the period, soon becoming
slight.

"Hugh Newbury" wrote ...


Martin, what's the 10-minute rule?

.... sorry Hugh, meant to write it in .... if you can't obviously see
that a thunderstorm has passed the 'station' or observing point, then
it is considered that the thunderstorm has ceased 10 minutes after the
last thunder heard.

Martin.


--
Martin Rowley
West Moors, East Dorset (UK): 17m (56ft) amsl
Lat: 50.82N Long: 01.88W
NGR: SU 082 023