Here's a little bit of reading regarding placement of weather instruments from the WMO-
http://www.wmo.int/pages/prog/www/IMOP/ ... MetObs.pdf" onclick="window.open(this.href);return false;
I think it's almost impossible in suburbia to get an uncompromised placement, especially on my measly 400 squares!
In the end I look at it as the instruments are taking readings at a microclimate level and then they are read as Mesoscale+ which makes mounting important but it depends how serious you are. I think this is the most true for the Thermo/Hygro which is easy to comp. over grass or near plants causes DP misreads due to transpiration, solar or thermal radiance over reading temps ect, it really turns into a nightmare quick... personally I run the most compromised setup, my anemometer is ok except it can't handle cloudy days in a row, my rain gauge suffers blocking on its western semi-circle and my thermo is probably the worst example... Mounted on a block rendered wall, under eave, facing north, over height(2m), gets direct sunlight at least twice a day including in the afternoon(worst-but depends on time of year),next to a twin head AC unit for the ducted whole house system and it was over grass but the grass has been replaced by river rock!
The rock has added another +0.7C-0.9C to the temp comp. But it will be exponential come summer!
Solution...
DIY FARS(Fan Aspirated Radiation Sheild), the pipe with the fan carries the sensor, it sits inside the gill screen(pancake stack), the fan runs from the solar panel array pictured during the day(also charges the batteries) and runs from the batteries by night. If I mount it where solar comp is still a noticeable problem I can mitigate by wrapping the mounting pipe in silver duct tape- not gaffer tape but the actual shiny insulation looking stuff!
I work on it between "other" weather technical projects so going is slow, might be ready next year???
Good luck nafets!