On Friday, August 14, 2015 at 7:29:21 PM UTC+1, Dave wrote:
Official Teignmouth Met Office Station rainfall 24hrs to 10am 14-Aug-15 was 50.1 mm or 1.972 inches in old money.

I can only remember one or two other occasions when 50mm has been exceeded.

50mm has a return period of 28 months in Penzance (based on 23 years of 09:00 to 09:00 records, so not a particularly rare event here.

Some years have seen 50mm recorded on 2 occasions, a mixture of winter & summer events.
1997 saw 53.1mm 7/11 & 52mm 3/8
2002 saw 84.5mm 13/11 & 62.5mm 31/12
2009 saw 65.2mm 24/4 & 51.8mm 16/7

My most notable rainfall event was when I recorded 90.2mm in 2 hours on 2/6/92 in Wootton Bassett (pre royal!) 92mm was recorded at Purton, 2 miles way, virtually none at RAF Lyneham. It made it into the MetO hydrometeorological bulletin. I even got a visit from the MetO (1 person. not the entire organisation!) and was handed satellite images (a novelty in those days) and a copy of the bulletin, a very pleasant surprise.

Graham
Penzance