https://droughtmonitor.unl.edu/About/WhatistheUSDM.aspx
> Who draws the map?
> Several authors from the NDMC, NOAA and USDA create the map. They take turns, usually two weeks at a time.
> How do they figure out where and how bad drought is?
> This is what makes the U.S. Drought Monitor unique. It is not a statistical model, although numeric inputs are many: [...]
https://droughtmonitor.unl.edu/About/WhatistheUSDM.aspx
> Who draws the map?
> Several authors from the NDMC, NOAA and USDA create the map. They take turns, usually two weeks at a time.
> How do they figure out where and how bad drought is?
> This is what makes the U.S. Drought Monitor unique. It is not a statistical model, although numeric inputs are many: [...]