Imagine that we take a section of the earth’s surface, a few dozen square miles in area, and permanently keep it heated to a temperature significantly above the boiling point of water. What effect will this have on the weather nearby? I imagine that you’d have a permanent updraft over the heated area and strong surface-level winds blowing into it from surrounding land. Would there be permanent storm systems generated by the artificial temperature difference? How far downwind of the affected area would unusual weather be noticeable for?
Well here’s the deal with weather modeling… it’s incredibly difficult. Prior to WWII, weather could be predicted with decent accuracy for only a few days ahead and sometimes not at all. Nowdays, with tons of computing power, new advances in chaos theory and 50+ years more experience, weather can be predicted with decent accuracy just a couple of days more than back in 1940.
You have already surmised the obvious, as for the rest, it would depend on the details. Who would be willing to devote time to figuring out? Probably not anyone with access to a serious model as they are usually busy trying to solve real world weather problems.
We’re talking about dumping a SERIOUS amount of heat into the atmosphere here, aren’t we though, my rather vague WAG is that the effect would be very significant locally and possibly be enough to upset all sorts of other systems globally (by ‘systems’, I mean things like the Gulf Stream, El Nino etc.).