The San Juan Through The Year

The San Juan is a true year-round tailwater. What changes isn’t whether you can catch fish—it’s how you fish, what the river gives you each month, and what style of trip (wade vs. float vs. euro) makes the most sense. Here’s the About Trout month-by-month breakdown so you can plan the perfect window.

Quick Navigation

• January
• February
• March
• April
• May
• June
• July
• August
• September
• October
• November
• December

January

The Fishing: Quiet river, cold mornings, and a lot of room to work. The fish settle into winter holding water, think deep and heavy. January is by far the least busy month of the San Juan River. We still guide our full 8 hour full day program.

What we do: Nymphing is the program—slow and deep is the method. We occasionally can fish to risers although it should not be expected. For those who want to try it is possible to throw smaller tandem streamer rigs.

Expect: Fewer anglers, colder weather, plenty of shots, and nymphing both with an indicator or a euro set up.

February

The Fishing: Still winter, but we can get some really nice warm days. The daylight is increasing and we can sometimes get lucky with more consistent rising activity. The end of February usually brings and uptick in streamer fishing as well.

What we do: Nymph heavy focus with more chances at rising fish and more streamer opportunities toward the end of the month. Junkier nymph rigs like mops and leeches. When conditions allow we can get some decent midge dry fly fishing. For streamers we’re usually leaning on smaller tandem rigs but we begin to find more success with the larger patterns at the end of the month.

Expect: Consistency—especially if you commit to good drifts and “winter water” over wishful thinking. We will seize whatever dry fly opportunity presents itself.

March

The Fishing: Spring starts to show up. The fish begin to become more “bug heavy”. We begin focus on patterns like foam wing emergers and root beer baetis. We usually get some decent baetis (BWO) hatches in the later part of March. The streamer fishing begins to get better as the brown trout are packing on weight after the spawn.

What we do: Nymphing as the backbone, with real opportunities at some great streamer and dry fly fishing when conditions line up.

Expect: Variety—plus the occasional curveball (wind, late snow, or off-color water). The anglers who adapt do best.

April

The Fishing: One of the best “learn the Juan” months. Comfortable days, active trout, and more predictable patterns.

What we do: Indicator nymphing and tight-line tactics both shine. This is also prime time to build skills—depth control, drift management, and reading lanes.

Expect: A very complete month—strong nymphing and enough dry fly and streamer windows to keep things interesting.

May

The Fishing: Spring momentum. More bugs, more options, and more days where the river feels like it’s giving you a gift.

What we do: Tight drifts, smart weight changes, and quick adjustments. May rewards anglers who stay present instead of running the same rig all day. May is when the river really beings to push us to fish what’s actively happening. We can start the morning heavy and deep and by the afternoon be fishing as shallow as 18″ under a double indicator set up.

Expect: Some flow variability depending on the year—when it bumps up, we fish smarter water (or float for comfort and coverage).

June

The Fishing: Summer starts. The river can get busier, but the fishing stays strong and the menu gets bigger. June begins to bring longer days offering us more options and more creative floats for our anglers. With an increase in flows it opens up more river and more opportunities to access parts of the Juan we usually can’t get into with a drift boat.

What we do: Nymphing stays the baseline, with opportunistic windows for dries and targeted streamer moments when the conditions are right. June is the beginning of big streamer season.

Expect: Longer days, more variety, and the start of “cover water and hunt” season.

July

The Fishing: Peak summer. Flows can be higher some years, and the river rewards anglers who understand soft edges, clean lanes, and good angles.

What we do: Client’s choice. Everything we offer fishes well this month. It’s up to the angler on how they want to spend their time on the water. That or Omakase

Expect: Strong fishing when you fish the right water the right way. When the river’s big, you don’t “fight it”—you read it. July is also perfect for “Super Full” days and evening dry fly floats.

August

The Fishing: Prime time. When August is good, it’s the Juan showing off—strong bug life, happy fish, and high-confidence days. WE LOVE AUGUST.

What we do: Mix the playbook: hunt feeding lanes, take the shots you’re given, and stay ready to switch gears.

Expect: Some of the most “fun” fishing of the year—variety, action, and enough windows to keep the day dynamic.

September

The Fishing: September is like August just with more refreshing weather. That being said the river is little busier this time of year but we know how to maneuver through the uptick in angler activity. September offers a taste of fall weather and very consistent fishing throughout the day.

What we do: September is where you can truly choose your style—wade, float, or a mix—based on your goals.

Expect: Comfort, consistency, and lots of angling options.

October

The Fishing: Fall perfection when flows cooperate. Crisp mornings, comfortable days, and trout that are locked in. That being said October is THE BUSIEST time on the San Juan. Weather is great fishing is better, who wouldn’t want to be here?

What we do: Nymphing is deadly, but October is also a month where being alert pays—small windows can pop up and you want to be ready.

Expect: Early starts on our end. If you wait to long the boat hatch can be pretty crazy. Classic San Juan fishing—clean drifts, great wading, and some of the best “every-cast-could-matter” days of the year.

November

The Fishing: Guide season. Fewer people, steadier days, and a return to fundamentals. We joking call November the “secret season.” Way less people with the first two weeks generally having similar weather to the end of October but without the fall colors. Keep in mind that it is the Southern Rockies and some years we start getting snow this time of year. If you’re looking for diversity in angling opportunity and less crowds, this is your month.

What we do: Deliberate nymphing with an eye on bigger meals when it makes sense. If you want to nerd out on approach and water-reading, November is money. Dry fly fishing is still very much a part of the day to day although this is truly the beginning of the end of consistency with dries.

Expect: Consistency and space—plus a river that rewards patience and precision.

December

The Fishing: Underrated hammer time. Cold mornings, fewer anglers, and the start of the winter “big fish” rhythm.

What we do: Mostly nymphing, with the last real dry-fly windows typically fading by mid-month depending on the year. Streamer fishing is an option if you’re a maniac but a good day in December is usually 8 eats.

Expect: Off-color water at times, technical drifts, and some of the most satisfying eats of the year if you commit to the program. When the weather begins to stay under freezing is when we see the lake “turn over”.

Planning Notes (Read This Once, Thank Yourself Later)

• Flows matter: The San Juan is always fishable, but your approach changes with flow and water clarity.
• Wade vs. Float: If flows bump or you want to cover more water, a float trip can be the most efficient way to fish prime lanes safely and comfortably.
• Bring the right gear: Cold months demand good layers and warm hands. Warm months still require smart sun and weather planning.

Book a Trip with About Trout

Ready to fish the Juan the right way—with a plan, clean rigs, and guides who live on this water? Tell us what month you’re looking at and whether you want to wade, float, or go full technique mode, and we’ll match the trip to the conditions.