I need a bit of help. While running RegCM4.6 coupled to CLM4.5, whether it is Tiedtke, Emanuel or Grell, there is a dry bias in my the United States (CONUS) domain, particularly over the eastern portion of the continent and especially over summer (we are seeing a dry bias in summer of ~50%. Default parameters are used in all cases. We have been able to reproduce observed precipitation better in Tiedtke by increasing the autoconversion coefficient and decreasing the below-cloud evaporation coefficient... however, I am curious if anybody else has had this problem, and what they have done to solve it.

Productive information about this issue would be much appreciated!

Best,

Matt

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