Yes, that is because of excessive rain. Some plants seem not to be able to control their water uptake, and the pods' skin literally splits open from being too full of water. They will form what is very much like a scab that you or I get after we manage to split our skin open - it's not attractive, but it's not dangerous, either. As long as any changes you see remain just at the surface and right along the splits, the pods are ok. Again, not pretty, but ok. If, however, the changes spread beyond the splits or start getting to the internal tissue of the pod, toss it.