I live in zone 5?
try a fungicide for the plants, this rainy weather...you may need to apply near daily. yup, I'm in zone 5.
It may be a calcium issue, a bit af lime may help.
I agree. Lack of calcium can cause this. I put tomato tone around my plants. It has a lot of calcium. There is also a spray product you can use to try and save them. Good Luck.
See if these help you.