Irrigation demand, coupled with the traditional dry summer season, makes for challenging water conditions near Dillon in late summer.
Low flow and high-water temperatures severely limit angling opportunities on the Big Hole River from July – August. Much of the river is typically closed to fishing while the sections that remain open fall under “Hoot Owl” regulations meaning that they are only open to fishing between midnight and 2 pm.
The Beaverhead and tailwater section of the Ruby River remain good options into August, but water clarity usually becomes an issue at some time in August when the reservoirs “turn over.”
Montana fly fishing trips to the Dillon area during the late summer are best planned at the last minute and condition dependent. There are windows of opportunity during this time that can result in some fantastic fishing, but the best approach is to “wait and see” as there are better, more reliable options on the Montana rivers near Bozeman during this time.
The upper Beaverhead River and entire Big Hole River closes to fishing on October 1.
Trico hatches are prolific on the rivers near Dillon during August and September. Periods of solid dry fly fishing can be found on the Big Hole during the spinner fall.
Dry/dropper setups are effective across the region during the late mornings when the spinner fall occurs, even when fish aren’t rising. Small Perdigon-style nymphs dropped 3-4’ below a hopper become standard when fishing the lower Beaverhead and Jefferson rivers in August.
Cranefly activity gets going on the Beaverhead River in August. Early and late sessions spent “dapping” dry/dropper rigs through riffles and along the willow-lined banks can result in some unexpected and explosive strikes.
Late August or early September cold fronts find their way across Southwest Montana each season, bringing a day or two of respite from the summer heat. Streamer fly fishing the upper Beaverhead River right after one of these cold fronts comes through – during cloudy conditions – is an incredible experience as trout seemingly move from everywhere to chase and explode brightly colored flies/
Fins and Feathers looks towards Dillon in the late summer when conditions are most favorable. Conditions vary yearly, but are generally best, this time of year, during late September.
Cool nights help bring the Big Hole back into shape, creating some terrific dry fly fishing on overcast days. Streamer fly fishing the Beaverhead and Jefferson rivers improves with cooling water temperatures in September too.
Our Montana fishing guides offer up a day or two on the rivers near Dillon to our guests when conditions are just right to add a bit of diversity on multi-day itineraries. Best suited for experienced anglers, day trips to the Dillon area this time of year typically involve a range of fly fishing techniques.
Fins and Feathers has been outfitting Montana fly fishing trips for over two decades on the waters of southwest Montana. Contact us to learn more about our guided fly fishing trips near Dillon.