I fished the Monnow at Skenfrith last Saturday for an hour and had two trout up to a pound and a small grayling. There was a hatch (in between the thunderstorms) of alder and yellow mays (not many of the latter). Only a few fish were rising and I failed on the dry. When I switched to sub-surface on a goldhead Princes Nymph (below), it had a much better reaction.

Good luck and let us know how you get on.

James