1. level ground, 10m X 7m, short irigated grass (or surface representative of general area). surrounded by fense.
2. No steeply sloping ground nearby (no hollow)
3. Away from trees, cars, buildings, parking lots, .etc (most important for precip. and wind)
4. All instruments should be on same site.
5. Area with little development
6. If changes in instrumentation or site (keep old instruments/site running for one year)
7. Inspect site/instruments once every 2 years