It's all about the coolant ...
When I lived in Alabama (read: where all the Jerry Springer guests live), you'd often see the AC spitting moisture out due to humidity if you were on a good beat down I-65. Don't even ask what happens if youre in the bayous down in Louisiana.
Try driving around in the Southeast USA
From what I've been told about the climate in Spain from folks I know that went over there, it's a drier hot than Alabama. Probably similar to what Australia has (well, maybe not that dry). I mostly agree with kirbycope on this one; get some quiet fans and good copper heatsinks. Make sure the heatsinks have some thermal paste between them and the chips you're cooling to ensure efficient heat conduction as well. There are always the closed fluid systems for cooling too. And if you really, _really_ want to get into it, take a tip from a Kiwi.