The Beaverkill is very low, which is not unusual for the month July in a dry year, and will be dependent on rainfall and cool evening temperatures to provide continued good fishing.
Hatches that are occurring include Sulphurs; various colors and sizes of caddis flies; Blue-Winged Olives and some Isonychia. We noticed numerous stonefly, small caddis and Isonychia shucks all along the streamside rocks.
Watch for Cedar Waxwings and other birds working the air above a stream; they will indicate a hatch in progress.
Other favorite Beaverkill flies include the Adams in size #16 or smaller, which works well when Isonychias are about. Small brown/gray parachutes flies (sizes #18 and smaller) worked well during a time when Sulphurs and Isonychias were seen on the water.
The best time for fishing in the heat of summer is early in the morning, before the sun is on the water, and also at dusk until (and just after) dark. Cloudy days are usually better than bright sunny days for catching rising fish.
If you are not successful in having a rising fish take your fly, try one that is a size smaller – or switch to 7X and midges in size #20 and smaller.