[quote=@PolkaDancer]Also just wondering, could things such as flooding the city or large scale disasters be done by us gods or not?[/quote]

Part of that would fall under the realistically arbitrary but also necessary rule of excessive destruction. Certainly you could make a river rise a few metres and burst its banks to cause some random destruction, and do so repeatedly, but on a city wide scale, that would take a while to have really catastrophic effects. Honestly I don't think the power limit (medium skyscraper an hour) I've set on the gods will ever be sufficient to change things like climate or tectonic plates far enough or suddenly enough to produce a noticeable effect. Those things are just so monstrously huge. 

The thing that bothers me so much about a nuclear explosion as opposed to other forms of destruction is that it's set off by an [i]object[/i]- A comparatively small one at that- and objects are fair game to create. Earthquakes, cyclones, mass floodings are all triggered by events, sometimes a long string of events going back quite a while. Could you engineer the kind of climatic events needed to pull stuff like this? Probably not, because the main limitation on your power is the time it takes to exercise, and events require much more precise timing, possibly in more than one place at once.

Within the boundaries of your divine realm, however, go nuts. Access from your divine realm to the mortal plane is limited by the size and number of portals you can maintain, though.