I was reading a notes on ws-2080 from http://lancet.mit.edu/~mwall/reviews/ws2080-amazon.html
and there is a note the rain collector has no guard around its collection surface. if the collector is in a windy location, the readings will be low as most of the water will blow out of the collection dish. you might want to build a vertical wall around the collector to block the wind.
and wonder what is a verticall wall around the collector ?
does any other weather stations like davis not have this problem?