Ground Snow Loads
Does SBCA have a state by state map for ground snow loads per the building code?
If you view the map you can see some areas require site-specific case studies to establish ground snow loads. It is always best to consult with local building departments to verify snow loads for particular areas.
There are some commercially available programs that aid in the calculation of ground snow loads, one of which is available from the Applied Technology Council. This web page can give you snow loads within seconds based on either street address or latitude/longitude. However, you should still verify that value with your local building code department.