Bacterial, fungal, or something else?

[FlipTX]

I've attached a picture of some of my tomato leaves. It's not the best photo quality so I'll do my best to describe what's going on.

I started noticing a few small dark brown spots with yellow margins on some leaves, a week or two ago. This was only on my Sugary plant; all others were fine. Then after our latest bout of heavy rain, I find grayish areas on many of the leaves of ALL my plants. The leaves quickly turn yellow and the grayish areas become thin and crispy. They are mostly on the lower to mid level leaves, of both my in-ground and container grown plants. None of the fruit show any symptoms, although most are only the size of marbles or ping pong balls so it's early. All plants are mulched and sprayed with Daconil on a 7-10 day schedule. I don't notice any powder or obvious fuzzy fungus on the leaves or stems.

The least affected plant is Marglobe although it's starting to show symptoms, too. The potato plants, which were planted earlier than the tomatoes, and the peppers which were planted at the same time as the tomatoes, don't seem to have any foliar symptons.

Are my plants goners?