If you can, go out with a magnifying glass and check out the undersides of your leaves. I tend to get hit with spider and/or russet mites, and they'll congregate on the underside of the leaves. Eventually they turn the tops of the leaves a kind of glossy purple/yellow color and the leaves start contorting before turning brown and drying out.

Just one thought of a possibility, not being able to see what your leaves look like. You could also do some google image searches to see if anything looks like what you have.

thanks...all of that makes sense. I never had mites on my tomatoes. Weird...