Many avid anglers target September as their preferred month for fly fishing in Montana. Once kids go back to school the amount of tourist traffic visiting the Big Sky state drops off dramatically so the casual anglers sneaking in a guided day of fishing on their Yellowstone Park vacation almost vanishes and the rivers are left to more serious fly fishers. Locals also begin turning their attention to the fall hunting season so the trout see relatively few flies in the Autumn months. September also offers some of the most pleasant weather of the year with dry weather, crisp mornings, and warm days. Fortunately the fishing can be very good in September with a mixed bag of dry fly fishing, streamer fishing and nymph fishing.
Where to fish? All of the favorite classics that fish well in the summer are still a good option in September. Legendary rivers like the Upper Madison, Yellowstone, Gallatin etc. still produce. One of the perks about fishing in September is that several of the lower elevation rivers also become a good option. Waters such as the Lower Madison, Upper Missouri, Jefferson and Lower Gallatin often get too warm in the popular mid summer months to produce good fishing. Once the nights become longer and temperatures begin to drop a bit these fisheries often hit ideal trout temperatures and once again become productive. The lower elevation waters often have lower trout counts per mile but often produce some of the larger brown trout in the region with a ten-pounder a possibility for a very lucky angler. Spring creeks are also an interesting choice for September. By the end of the month the fall baetis hatch is producing steady mid day match the hatch fishing. Earlier in the month terrestrials are the main dry fly staple but nymphing the troughs with midge larva. Usually the famous spring creeks near Livingston only have a few rods a day in September so you can have all of the best runs available without a lot of other anglers around (just be prepared for technical fishing).
Montana Angler Article Link
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