How can anything be too dry at present? Wonder if they normally live under your grass and are trying to escape the wet? I don't know why anyone would want to get rid of ants, there are tens of millions of them to each one of us, so do-one can win that one. (Mind, when I lived in Zambia, I did sometimes wonder why my four and a half million were all in my kithen at once!) I must confess I just ignore them, unless they insist on pushing a plant out of its pot, a rare occurence, I usually just repot the plant. They may just be getting into flying mode for mating, and if left be will settle down to their usual appearance. The boiling wate method seems unnecessarily cruel to me, how would we like it? If you really must get rid of them, there are less dreadful ways of doing so, various powders and liquids that poison them, hopefully less agonisingly than boiling water would.