And just to emphasise the points Stephen made about the effect of wind eddies.

My site is well exposed but is often windy and the rain is often dense and fine
(many droplets swirling around). Here is a comparison for annual rainfall of
Davis AWS (1.4m above ground) versus manual 5" check gauge on the ground in
short grass.

2005 AWS 1263 mm Gauge 1406 mm (9% deficit with AWS)
2006 AWS 1333 mm Gauge 1544 mm (14% deficit with AWS)

I'll have to live with that, using the manual gauge for the definitive record
and the AWS for recording interesting rainfall event timings etc.

Will (Haytor, Devon, 1017 feet asl)
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