It is late blight time. Looks like the early stage of LB.

Doesn't look like late blight to me. (But if the plants collapse in several days, we'll know it is.)

That said, doesn't look like verticillium either.

Some leaf edge browning. Perhaps short of water?

Are they in pots or the ground?

They are on ground, same spot every year cause I have no other. Can't believe late blight or they would be dead-dead, by nows. I think, THINK, that it is the same thing that kills my plants every year just as they start producing good. I have about 15 varieties, both hybred and OP and it seems to affect (effect) them all the same. Water is 2 drippers a foot apart, one on each side of plant. Right now they are getting a gal a day each. Had lots of rain earlier.
KennyP

One gallon a day isn't much for a full size tomato plant.

Try running them for a longer time and /or supplementing with hand-watering or an extra dripper per plant.