No, "stunning" doesn't refer to the skies over the marina after a day of rain, though we've had a few of those.
And shocking isn't a reference to the dreadful weather we've had over the last few days, though most of yesterday and the early part of today were really quite pleasant.
In fact, "stunning" and "shocking" refer to work that we saw being done in the marina this morning. Four men in two small boats were buzzing slowly up and down the marina pound, round and round. Each of the men held a fishing net. The larger boat went ahead, trailing an array of electrodes through the water in front of it. These delivered pulses of electricity into the water, shocking and stunning the fish. These then floated to the surface, and each of the men reached out their nets from time to time, to catch one of the fish and dump it into a plastic box on the boat.
I don't know who this team was working for - CRT, the Environment Agency? - but the fish they were taking out of our water were of a "non-native, invasive species". So said one of the men to one of the moorers, though they didn't say which species it was, and I couldn't ask because I wasn't close enough. My guess is it was zander, which I know are fished from these waters. They can be huge!