Possibly. Could also be the onset of late blight or any of the other countless tomato foliar fungal issues. Can you post photos?

For the first time in all my years of growing tomatoes in containers - and almost always cherry tomatoes - I have disease issues. Primarily powdery mildew. But also a drying and browning of the ancillary leaves or suckers that emerge from the nodes of the larger flower and fruit bearing stems. The stuff that gets pruned out if you prune your 'maters :-) And my Sweet 100's are more severely affected than the Sungolds, which makes sense as Sungold has much greater disease resistance. The Sweet 100's look dismal and I am contemplating riping them out entirely. But they are still producing fruit, which is untouched. They have stopped flowering, though.

Sungold is still flowering and fruiting. And I do groom out the worst looking foliage pretty much daily. There is really nothing odd in our weather this season that would have prompted this so I am at a bit of loss as to the cause.

I really do not have a good location to grow tomatoes in my garden - too much shade in general - so will have to reevaluate my plans for next season. It might be the first time in more than 25 years I don't grow my own cherry tomatoes. Sad :-(

A pretty bad year here for tomatoes too. All 20 of the early plants are now shot and the 6 that I planted late (mid Jun) are hurting bad from moisture loving plant diseases. The type of scourge/blight that works its way up the plant from the bottom turning green leafs yellow to brown to dust exposing the remaining tomatoes near the top to sunscald resulting in a mealy mater mess no better than winter time store bought.

It may actually be septoria.

This is an Opalka, This one seems to be hit the hardest, but honestly all of them have it.

pic 1 looks like late blight. pic 2 looks like septoria. the late blight map shows that there's late blight in PA along the MD border.