Lots of sunshine and bluebird days are ahead, and it’s going to feel a bit more like the end of summer than the start of October in Yellowstone this week. Our favorite fall pursuits (chasing Baetis hatches and migratory fish) may have to take a back seat for a few days. Instead, this warm, sunny stretch could offer a few more opportunities to fish terrestrials like hoppers and ants before fall finally takes hold.

HERE ARE THIS WEEK'S STANDOUTS. 

SLOUGH CREEK, LAMAR RIVER & SODA BUTTE CREEK

The summer-like afternoons ahead this week will be perfect for chasing cutthroat in the Northeast Corner. Cold nights will keep things quiet early, so there’s no reason to rush out in the morning. Give water temperatures a chance to warm and look for the best activity from late morning through the afternoon. Maybe swing for fall-run fish on the Madison in the Park for an hour or two first thing in the morning, then head up to the Northeast Corner.

This stretch of warm, sunny weather should extend the terrestrial season a little longer, with small hoppers, ants, and beetles all worth fishing while afternoon temperatures remain mild. Focus on all the usual spots along undercut banks, grassy edges, and pieces of fallen bank. At this point in the season, it’s also worth dropping a nymph below a terrestrial through any of the deeper runs.

Baetis and other fall mayflies remain in the mix, though the bright conditions won’t be ideal for substantial hatches or widespread rising fish. Still, watch for localized activity, especially in the afternoon.

These may be some of the last opportunities of the season to enjoy warm afternoons and terrestrial fishing in the Northeast Corner. With fall colors, hungry cutthroat, and some of Yellowstone’s best scenery, it’s a pretty good week to take advantage.

FIREHOLE RIVER

Warm, sunny weather will make for some sparse days if you’re looking for fall hatches of Baetis mayflies and rising fish on the Firehole this week. White Miller caddis should provide some dry-fly opportunities throughout the river, with fish cartwheeling to eat these size 16 caddis anytime the wind lays down from late morning through the evening.

As always, you can dig into the soft-hackle box for some of the most fun swing fishing found anywhere. This is a great time and place to break out a micro-Spey rod, Scandi line, and a selection of small soft hackles.

MADISON RIVER

With bright, sunny weather in the forecast, the most productive windows to target fall-run fish moving up from Hebgen lake will be early in the morning, and later in the afternoon/evening when light levels are at the lowest. 

These migratory browns and rainbows are much more comfortable and active under low-light conditions, and fishing will slow considerably once the sun gets high on a clear day.

GALLATIN RIVER

The Park stretch of the Gallatin will be a solid option this week for reliable nymph fishing and some stellar fall scenery. Warm afternoons are a good time to drift a small hopper or flying ant pattern through tight lies along undercut banks, especially while these warm, sunny conditions hang on.

Sparse hatches of Baetis mayflies may bring the odd fish to the surface in the afternoons as well, despite the bright conditions. Don’t expect widespread rising activity, but keep an eye on slower pockets and softer edges where a lone bbt may take advantage of the bugs.

GARDNER RIVER

Speaking of taking advantage of some of the last good terrestrial days, the Gardner River is a great option this week for a single hopper or hopper-dropper rig. The rough-and-tumble pocket water of the lower river provides plenty of opportunities to prospect with a dry fly, especially during the warmer afternoon hours. 

Brown trout are also starting to filter into the river from the Yellowstone, adding another dimension to the fishing as we move toward October. It’s still early in the fall migration, but these fish will become important in the weeks ahead. Nymphing the deeper runs and pools or working a small streamer through likely holding water can be a good change of pace when fish aren’t looking up.