On 26/08/12 11:41, Norman wrote:
Martin Rowley wrote:

....

... yes, to be utterly boring (but correct) even with all the fancy stuff
available, it is essential in my view to have some sort of check gauge.
Doesn't have to be a 'standard' copper effort - I've got one of those, but I
also have a 'cheapo' 3 inch alongside to double-check. It needs 'correcting'
- roughly uprating whatever value is given by ~10% - but allowing for that it
gives good service (and has done for many years).


I agree, Martin. My Davis VP consistently measures totals around 15-20% lower
than I measure with a standard 5" copper gauge. Reliance solely on this level
of AWS is unlikely to result in accurate rainfall totals.

I regularly keep track of the difference between the AWS and the std
gauge. This month so far:

AWS 80.0mm, Std G 108.2mm

This year:

AWS 511.6mm, Std G 678.6mm

Hugh

--

Hugh Newbury

www.evershot-weather.org