Not enough water to the top of the plant.

To determine if the soil (or potting mix?) is wet, most or dry, stick your finger in it. And then decide whether your self-watering containers are working.

It doesn't look like a watering issue.. It seems more like a bacterial disease, most likely caused by the heavy rains. Even in containers it's very possible for surrounding soil particles to splash onto the lower leaves and facilitate an infection. You always want to mulch the soil (2" or so) below tomatoes to keep bacteria and fungal spores from splashing onto the plants.

There aren't many effective treatments for bacterial diseases but you could give this bleach spray a try: Look at the back of the bottle and it'll tell you the composition of the product, either 6% or 8.25% hypochlorite.

6% bleach recipe: 7 ounces bleach to 1 gallon water - few drops dish soap (surfactant)

8.25% bleach recipe: 5 ounces bleach: 1 gallon water - few drops dish soap (surfactant)

Spray the entire plant (both sides of the leaves). You'll notice healthy looking leaves appearing to die during the next day or two after spraying; they were infected with the pathogen as well. Remove all dead and dying leaves a few days following the treatment. Always be cautious NOT to touch other plants after handling one that is diseased as you will cause it to spread. Wash your hands and sterilize your tools (anything that touched the plant) before you begin tending any other plants.