[Proj] proj4 definition for transverse mercator projection from RegCM3 model for North America

[Hailey Eckstrand]

I've figured out my problem. The projection was documented as transverse
Mercator as there was no option for rotated Mercator in the netcdf metadata
requirements. The projection type ended up being Swiss oblique Mercator & the
north_easting & false_easting were off by 25000. 
Thanks for all the help. 
The final correct definition ended up being:

+proj=somerc +lat_0=47.5 +y_0=3150000.0 +x_0=3900000.0 +lon_0=-97.0 +k_0=1.0
+units=m +a=6371229.0

Hailey