Solar Production is reduced on a rainy day. But as an example, I show a full cloudy days production. This time of year I will produce about 50-60kWH. Today it was avout 10 kWH. Not terrible. I noticed that my newer panels are producing a lot more per panel than the ones that are 12 years old on rainy days. The newer technology in the panels has improved lower level light collection and production. If you see this image the lower 30 panel array (which is older) produced about the same as the garage arrays with the newer panels (only 20 total).