Yes, it certainly could be the rainy weather all the east coast has been having. If your soil doesn't have a chance to drain but is continually filled with water, the plant roots begin to suffocate.

I'm still picking green and wax beans, but the lower leaves really look tacky, yellowing and dessicated. The tops are still green and healthy, so I guess they'll keep producing unless the bottom of the plants die.

As for helping them, I'd let them be for a while. See what happens. If you have sandy soil, the original fertilization gets carried down as the rain drains into the subsoil, so when things have stabilized, I'd add a small amount of a balanced fertilizer to see if that's useful. Or your plants may perk up without additional fertilizer.

Sandy soil? That's a good one! I'm falling over LOL...

clay, clay, and more clay. We've been amending for 10 years, but I often think it's hopeless. .

Like tomatoes, beans are easily damaged by very small amounts of the herbicide aminopyralid, which can persist in compost, manure and hay. If you amended your soil with purchased stuff, that could be an explanation.

Here is a link that might be useful: NC State herbicides in hay and manure