Swiss bureaucrat Sepp Blatter in an interview with L'Equipe --
Le président de la FIFA n'exclut pas que «des rencontres aient lieu dans des pays proches» du Qatar.
Neighbouring countries could host matches, something that was not mentioned in Qatar's bid. Unfortunately, a cursory look at a weather map shows that all the countries near Qatar share its weather, although you could probably find some cooler parts in Iran or northern Iraq, which is presumably not what anyone who voted for the bid had in mind.
As the Wikileaks document dump shows in another context, it's important to consider the possibility that there is no deep or hidden explanation for the strange outcomes of international relations. It's just that there's a lot of stupid and superficial people at the top of these organizations. Sepp Blatter really thinks that 45C weather is just a minor detail in his credential of the first Arab-Muslim World Cup.