Given what jcf has said then the tropics, generally, would not be too big an issue. Tropical environments rarely get over 35°C because the moisture in the air absorbs heat (as humidity). It’s when you get into tropical & sub-tropical deserts that you’d have issues because in the summer/dry months, & sometimes even in the winter/wet months temperatures are regularly 45°C & higher, some regions regularly reaching 50/55°C.
However, that being said, the humid tropics are not a good place for metals generally, especially dissimilar metals, because electrolysis is accelerated by the humidity. In coastal regions, where salt laden air is also a factor, the tropics are down-right cruel to dissimilar metals. Just imagine one of the early steel-block/aluminium-head motors running salt water through its cooling system, instead of inhibitor-laden coolant.