Late Summer Trout Bonanza on the Big Horn in Montana

Good morning anglers, this is Artificial Lure bringing you your up-to-date fishing report for August 16, 2025, right here in and around *Big Horn, Montana*. Let’s kick things off with the weather: We’re enjoying a classic late-summer day, with sunrise at 6:12 a.m. and sunset set for 8:22 p.m. The forecast calls for mostly sunny skies and light winds—a beautiful morning to be out on the water, though heat can ramp up quickly through the afternoon, so pack the sunscreen and hydrate. As reported by KLTZ, Eastern Montana is facing a hot stretch, so expect those midday hours to push the upper 80s and possibly into the low 90s, especially in the open valleys. No tidal swings here, but river flows are steady and clear thanks to a mild week with just a touch of overnight chill, which always helps spur fish activity into the early hours. Now, let’s talk fish. The Big Horn River is famous for its trout, and today’s action reflects how productive August can be post-runoff. Local guides have seen strong numbers of healthy rainbows up to 20 inches and plenty of chunky browns in the teens. Word on the water yesterday was midge and scud patterns are producing well, especially in the early morning when the water’s cooler. Fish are feeding well before all that bright August sun hits—expect a solid window from about sunrise through late morning. By early afternoon, activity slows, so target deeper runs, especially below Afterbay Dam and in the braids near Three Mile. Those chasing numbers should swing by Ok-A-Beh Marina and try their hand at the afterbay for hard-fighting rainbows and the occasional carp crash in the shallows. As the sun crests, fish are retreating to the cool, oxygen-rich flows below the Boysen. Devil Canyon Overlook is always a top producer for both quality fish and a heck of a view and don’t skip Horseshoe Bend for panfish and an outside shot at a walleye. Best tackle for today: The classic nymph rig is king—think size 16-20 red or olive midges and patterns like the Ray Charles or sowbug. Anglers are also doing well on small black or olive Woolly Buggers retrieved slow. If you’re working the shallows, try a Parachute Adams or CDC Caddis close to dusk. For spin fishers, small silver Panther Martins or a Mepps Aglia in gold is drawing strikes. Worms drifted on light tackle are picking up trout at first light, and corn’s been reported to tempt a few of those carp. Bait fishing is legal in some stretches, so check regs before tossing anything natural. Grasshoppers are prevalent and can be deadly—tie on a hopper pattern and let it drift naturally along grassy banks late morning through afternoon. The hot spots today: - The braids at *Three Mile Access*—deadly for browns staging in cooler current. - *Below Afterbay Dam*—tried and true, especially with nymphs right along the seams. As always, remember public lands and fire restrictions are in effect, so keep your camps and banks clean and safe. Fires are a no-go right now across much of the This content was created in partnership and with the help of Artificial Intelligence AI.