CFS: 363

Water Temp: 47-52°F

Dries: October Caddis, BWOs, Mahogany Duns, Brindle Chutes, Small Terrestrials

Nymphs: Pat's RL, Perdigons, San Juan worms, STREAMERS

After enduring a week of solid smoke blanketing western Montana, we finally received some much-needed rain, and the air is now crystal clear. The precipitation also added to our streamflow and dropped the average water temp into the high 40s:

The downside to the temperature change is that the mornings and early afternoons have been tough fishing, at least for dry flies. If you enjoy fishing streamers, the mornings are an excellent time to come out. We're starting to see some bigger fish chasing buggers, sculpins, and rubber-legged streamers like the JJ Special. Nymphing is also a viable option in the morning; the San Juan worm has reigned supreme the past few days, but large stonefly nymphs with a small beaded dropper behind it have also been working.

If dry flies are your preference, I would recommend postponing your fishing until the mid-afternoon. My wife and I went out the other day and fished from 3:30 to about 6, and saw a number of hatches, including mayflies, tiny dark midges and October caddis (although nymphs were the only thing producing since it had rained earlier that morning). The Brindle Chute works as a great attractor for both Mahogany Duns and October caddis (depending on the size), and a size 18-20 Adams or Trico would work best for the midges.

The next couple weeks are forecast to be in the 60s-70s for daytime highs, and that will likely keep the terrestrials active into October. Try a Fat Albert or a small hopper with either a crippled emerger or a small beaded nymph a couple feet behind it. The fish will often eyeball the hopper and then take whatever is behind it.

We are going to stay open every day through October and then go to our limited winter hours starting in November, so we hope to see you in the Mercantile on your way up or down Rock Creek!

CFS: 336

Water Temp: 55 - 62°F

Dries: Hoppers/Ants/Beetles, Purple Haze, Mahogany Duns, BWOs

Nymphs: Peacock Stone, Prince Nymph, Green Copper Johns

Young Sam with a beautiful brown trout

We can feel fall approaching with each passing day; the nights have been longer, the mornings colder, and the bigger fish have started to move more as the water temps go down.

Fortunately, we've still had enough warm weather in the middle of the day to activate the terrestrial flies. Hoppers have been the most popular choice, but ants, beetles and rubber-legged stimulators have been great options too.

In the evenings, smaller mayflies have been the fish's preferred bug. A yellow PMD or a Mahogany Dun will work on the warmer days, but if you have any clouds/precipitation, try a Blue-Winged Olive instead. Attractors like the Purple Haze and the Brindle Chute are great "all-around" flies to simulate these patterns.

Green has been the best dropper color the past couple weeks; try a mid-sized hopper with a green Copper John or Zebra Midge 1.5 ft - 2 ft behind it. The other option would be to fish a double-nymph rig. If you go this route, use a big stonefly nymph with some weight as your main, and trail the small dropper.

At some point this month, we'll start to see the October caddis flying. Keep an eye out for the orange caddis nymphs crawling on the rocks as a harbinger of bugs to come. With there being more water than usual this year, the September fishing should be great on Rock Creek!

CFS: 421

Water Temp: 56 - 65°F

Dries: Spruce Moths, PMDs, Hoppers/Ants/Beetles, Red Attractors

Nymphs: Flashback stoneflies, Pheasant Tails, Copper Johns

As we move into mid-August, we finally see the high water working in our favor. The average streamflow this time of year is 300 cubic feet per second, but this August, we have been averaging an extra 100 cfs over that norm. This has created some better fishing conditions, especially in areas where the water typically gets too skinny.

The terrestrial season has also been very good this summer. The combination of a grasshopper with a small beadhead dropper has been pulling out some nice trout:

In addition to the hopper fishing, Spruce Moth patterns have been the other popular terrestrial. The hatch hasn't been prolific this year, but when you see them flying in the mid-mornings, it'll be a good idea to put on either a spruce moth pattern, or a large tan elk-hair caddis.

Attractors are the other way to go with your dry flies. Most people are keying in on purple, of course, but red is arguably more effective during the month of August on Rock Creek. This is the time to fish your stock of red humpies, royal trudes and wulffs, or any big stimulator or hopper with red.

If you hit one of those points of the day where the fish aren't keen on coming up to the surface, the combination of a flashback stonefly with a small copper john trailer is a great tandem to use for scouring the bottom. Fair warning though; you will catch more whitefish with this set-up.

Overall, it has been a very good summer for fly fishing Rock Creek. If the water stays higher than normal into September, we should have excellent fall fishing as well!

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73 Rock Creek Rd, Clinton, MT 59825, USA

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