Climate Temperature Forecasting

[the_photon]

Hey all,

I am wondering what kinds of models, circulation cycles, etc. are used by the National Climatic Data Center to predict temperatures over the long range (e.g. two or three months). I certainly understand that for most of the western united states, things like sub-surface temperatures in El Nino zones are used to predict precipitation amounts over the next three months, but what about temperature? What exactly goes in to a long range temperature forecast?

If you're not wanting to explain the who smash, a link or reference would be helpful.

Thanks,

the_photon