“Come Rain or Come Shine“. Willis Eschenbach tells us that Global Warming will be good because “a warmer world is a wetter world”. For the USA anyway. So far, anyway. That seems to be the entire argument.
Wott's Up With That?
A response to Climate Change disinformation at wattsupwiththat.com
Wott's Up With That? 
Why is he using rainfall data from 1895-2009, when the usual AGW dates are 1975-2009?
(UPDATE) The usual climate model generalization is that there will be less rain and snow where there isn’t very much (the Southwest), and more rain and snow where there is a lot (the Northeast).
Figure 4 might suggest the latter.
Money quote:
“I have long claimed that “a warmer world is a wetter world”. I have said this without any actual data”
Good for you, Willis. The first step in recovery is acknowledging you have a problem