Sas, anytime your fishing in the evening along a stream, look skyward, if a spinnerfall is gonna happen, the air will be full of bugs, sometimes up towards the treetops.
of course, at times they will get very close to the water, then the wind will pick up, it may rain, or some other cosmic event will take place and they will simply vanish.
but if they stay and hit the water, it gets very, very, good!
plus, spinners are one of the easiest bugs to tie! we had to tie up some bigger ones this past weekend at penns while eating breakfast. we had some rusty spinners for a hendricksons, but there were also march browns in the mix, so we tied up some #10 rusty spinners, which worked like a charm the next evening.