These symptoms look quite typical for tomato foliage late in the summer, and appear to be Early Blight and perhaps a bit of Septoria Leaf Spot. Both fungal leaf infections are very common, and some tomato varieties are more resistant to them than others. Weather does play a role, with wet foliage being easier for spores to infect; if plants are watered in such a way that wets leaves, that can promote infection, though it can happen even if you only water the soil. You can learn about identifying and managing/suppressing tomato problems (including these two infections plus heat stress) in our Key to Common Problems of Tomatoes web page.

Miri

thanks, Miri!

You're welcome!