My tomatoes have been doing very well, until recently when I began noticing brown/black lesions on the leaves and now the tops of some fruit are beginning to turn brown as well. I have never had any problems with tomato diseases and I am at a loss. Any ideas on what it could be and / or what to do about it? It is affecting about 6 plants right now. I suppose it could have something to do with the fact that it has been very hot and humid for the past week.

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