We are smack in the middle of winter here in the Flathead Valley. The last week has been fairly mild. Thoughts of fishing are on the brain. Water temps and flows are stable on the Flathead and have been for a while – a good indication the river will probably fish ok in the afternoons. Flows and temp are a good thing to check before a winter outing. Dropping temps and/or rising flows typically are not what you want. Have a look at our River Flows page for real time info. It’s also a good idea to focus your energy on the warmest part of the day – the afternoon.

The Flathead River, Lower Swan River & Thompson River are the closest options Flathead Valley anglers gravitate to if they don’t want to make the haul to the Missouri. Fishing can be quite good in the winter months.

Flathead River Winter Fly Fishing Conditions

Keep in mind when heading out in the winter that the ramps and river can be choked up with snow and ice. Chains and a shovel are a good idea to throw in the back if you are wanting to trailer a boat along. Or just go wade fish and leave the  boat in the garage until things thaw a bit. Kokanee Bend and Presintine bar can be a no go if there is snow on the valley floor. Keep that in mind when planning a float. The river can also get ice jams when temps drop into the single digits. Several days of above freezing usually will clear things up.

Flathead River Winter Fly Fishing Techniques & Flies

We are typically nymphing and slow trolling/swinging streamers in the winter months. Trout spey rods are a really fun way to fish in the winter and they provide the extra excitement of dialing your two hander cast. Short shooting heads with light tips are the easiest way to swing a sizable streamer and get some depth. We have several accomplished spey casters who can take you on the river and show you the runs and techniques necessary to catch a few fish out there. Otherwise, standard winter nymphs will be the most productive. Tung Pheasant tails, Tung Prince nymphs, pinkish jiggy nymph variations in a variety of sizes, San Juan worms, Tung stones, Tung turds, perdigons and whatever variation of all of these you want to throw. If you are tying your own just throw in a UV pink thorax and call it a winter fly. We’ve tried all sorts of streamers out there and they all work. A classic conehead crystal bugger is hard to beat but chicks don’t dig dudes unless they are throwing 8″ articulated beastly man flies. The occasional dry fly event happens out there too. Midges can get some fish up on a warm afternoon from time to time. A tiny purple haze or para adams will do usually. A midge cluster is also a good one to throw and fairly visable.

Flathead River Cutthroat

Flathead River Winter Fly Fishing Guides

Finding the right type of water can also be a bit of a learning curve in the winter months. Slower, deeper, boring water is where you will usually find fish. Slow inside bends with some depth or a deep slow shelf drop off, deep slow eddy lines, deep slow back water seams and slack pools, etc…deep, slow. It’s a good idea to have a few rods rigged when heading out in the winter. A couple different depth nymph setups are helpful to efficiently cover a run.  One with some bigger stonefly/worm/prince flies and one with some smaller pink jiggy/prince/p-tail nymphs on lighter tippet. Change your depths until you find some fish then move to another spot and do the same. Sometimes you gotta go deeeep. Again, if you want to learn the spots, technique, depths etc, then hire a guide and pick his brain. Give us a call if you want to get out on the water this winter. We have several jet boat captains, spey casters, and accomplished winter fly anglers who love guiding the Flathead River in the winter months.

Jason Lanier
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