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Big Thompson River Fishing Conditions
75°F
| Day | Condition | Temperature | Precipitation | Rain Chance | Wind | Humidity | Pressure |
|---|---|---|---|---|---|---|---|
|
Tomorrow
3:00 pm
|
 broken clouds
|
59° | 83°°F | 0 inch | 0% | 9 mph | 43 % | 14 psi |
|
Sun Aug 26
3:00 pm
|
 light rain
|
54° | 85°°F | 0.02 inch | 59% | 10 mph | 71 % | 14 psi |
|
Mon Aug 26
3:00 pm
|
 light rain
|
61° | 84°°F | 0.01 inch | 30% | 10 mph | 64 % | 14 psi |
|
Tue Aug 26
3:00 pm
|
light rain
|
60° | 82°°F | 0.03 inch | 86% | 10 mph | 75 % | 14 psi |
|
Wed Aug 26
3:00 pm
|
moderate rain
|
58° | 78°°F | 0.04 inch | 100% | 8 mph | 68 % | 14 psi |
| Hour | Condition | Temperature | Precipitation | Rain Chance | Wind | Humidity | Pressure |
|---|---|---|---|---|---|---|---|
|
Tomorrow
9:00 pm
|
broken clouds
|
71° | 75°°F | 0 inch | 0% | 7 mph | 36 % | 14 psi |
|
Tomorrow
12:00 am
|
broken clouds
|
66° | 70°°F | 0 inch | 0% | 8 mph | 43 % | 14 psi |
|
Tomorrow
3:00 am
|
broken clouds
|
61° | 61°°F | 0 inch | 0% | 7 mph | 43 % | 14 psi |
|
Tomorrow
6:00 am
|
broken clouds
|
59° | 59°°F | 0 inch | 0% | 7 mph | 42 % | 14 psi |
|
Tomorrow
9:00 am
|
broken clouds
|
75° | 75°°F | 0 inch | 0% | 3 mph | 29 % | 14 psi |
|
Tomorrow
12:00 pm
|
broken clouds
|
83° | 83°°F | 0 inch | 0% | 9 mph | 26 % | 14 psi |
|
Tomorrow
3:00 pm
|
broken clouds
|
78° | 78°°F | 0 inch | 0% | 6 mph | 34 % | 14 psi |
|
Sun Aug 26
6:00 pm
|
light rain
|
68° | 68°°F | 0.02 inch | 59% | 5 mph | 59 % | 14 psi |
|
Sun Aug 26
9:00 pm
|
overcast clouds
|
66° | 66°°F | 0 inch | 0% | 4 mph | 69 % | 14 psi |
|
Sun Aug 26
12:00 am
|
overcast clouds
|
63° | 63°°F | 0 inch | 0% | 5 mph | 70 % | 14 psi |
|
Sun Aug 26
3:00 am
|
broken clouds
|
57° | 57°°F | 0 inch | 0% | 9 mph | 71 % | 14 psi |
|
Sun Aug 26
6:00 am
|
 scattered clouds
|
54° | 54°°F | 0 inch | 0% | 10 mph | 66 % | 14 psi |
|
Sun Aug 26
9:00 am
|
 scattered clouds
|
74° | 74°°F | 0 inch | 0% | 6 mph | 39 % | 14 psi |
|
Sun Aug 26
12:00 pm
|
 few clouds
|
85° | 85°°F | 0 inch | 0% | 8 mph | 25 % | 14 psi |
|
Sun Aug 26
3:00 pm
|
light rain
|
75° | 75°°F | 0.01 inch | 20% | 5 mph | 39 % | 14 psi |
|
Mon Aug 26
6:00 pm
|
light rain
|
68° | 68°°F | 0.01 inch | 23% | 8 mph | 56 % | 14 psi |
|
Mon Aug 26
9:00 pm
|
light rain
|
65° | 65°°F | 0.01 inch | 30% | 6 mph | 61 % | 14 psi |
|
Mon Aug 26
12:00 am
|
overcast clouds
|
62° | 62°°F | 0 inch | 0% | 9 mph | 64 % | 14 psi |
|
Mon Aug 26
3:00 am
|
 few clouds
|
61° | 61°°F | 0 inch | 0% | 10 mph | 58 % | 14 psi |
|
Mon Aug 26
6:00 am
|
scattered clouds
|
61° | 61°°F | 0 inch | 0% | 9 mph | 57 % | 14 psi |
|
Mon Aug 26
9:00 am
|
overcast clouds
|
75° | 75°°F | 0 inch | 0% | 5 mph | 34 % | 14 psi |
|
Mon Aug 26
12:00 pm
|
broken clouds
|
84° | 84°°F | 0 inch | 0% | 1 mph | 22 % | 14 psi |
|
Mon Aug 26
3:00 pm
|
overcast clouds
|
80° | 80°°F | 0 inch | 0% | 3 mph | 28 % | 14 psi |
|
Tue Aug 26
6:00 pm
|
overcast clouds
|
68° | 68°°F | 0 inch | 0% | 10 mph | 53 % | 14 psi |
|
Tue Aug 26
9:00 pm
|
light rain
|
60° | 60°°F | 0.03 inch | 86% | 5 mph | 75 % | 14 psi |
|
Tue Aug 26
12:00 am
|
broken clouds
|
60° | 60°°F | 0 inch | 8% | 6 mph | 69 % | 14 psi |
|
Tue Aug 26
3:00 am
|
overcast clouds
|
60° | 60°°F | 0 inch | 0% | 9 mph | 62 % | 14 psi |
|
Tue Aug 26
6:00 am
|
overcast clouds
|
60° | 60°°F | 0 inch | 0% | 9 mph | 53 % | 14 psi |
|
Tue Aug 26
9:00 am
|
overcast clouds
|
75° | 75°°F | 0 inch | 0% | 3 mph | 29 % | 14 psi |
|
Tue Aug 26
12:00 pm
|
overcast clouds
|
82° | 82°°F | 0 inch | 0% | 2 mph | 22 % | 14 psi |
|
Tue Aug 26
3:00 pm
|
light rain
|
79° | 79°°F | 0.01 inch | 30% | 8 mph | 29 % | 14 psi |
|
Wed Aug 26
6:00 pm
|
moderate rain
|
69° | 69°°F | 0.04 inch | 100% | 4 mph | 54 % | 14 psi |
|
Wed Aug 26
9:00 pm
|
broken clouds
|
61° | 61°°F | 0 inch | 0% | 8 mph | 68 % | 14 psi |
|
Wed Aug 26
12:00 am
|
broken clouds
|
60° | 60°°F | 0 inch | 0% | 7 mph | 63 % | 14 psi |
|
Wed Aug 26
3:00 am
|
scattered clouds
|
59° | 59°°F | 0 inch | 0% | 8 mph | 57 % | 14 psi |
|
Wed Aug 26
6:00 am
|
broken clouds
|
58° | 58°°F | 0 inch | 0% | 8 mph | 55 % | 14 psi |
|
Wed Aug 26
9:00 am
|
broken clouds
|
72° | 72°°F | 0 inch | 0% | 1 mph | 34 % | 14 psi |
|
Wed Aug 26
12:00 pm
|
scattered clouds
|
78° | 78°°F | 0 inch | 0% | 8 mph | 28 % | 14 psi |
|
Wed Aug 26
3:00 pm
|
overcast clouds
|
71° | 71°°F | 0 inch | 0% | 7 mph | 43 % | 14 psi |
|
Thu Aug 26
6:00 pm
|
light rain
|
66° | 66°°F | 0.04 inch | 100% | 4 mph | 62 % | 14 psi |
Flow (CFS) : 266
Best Section:
Below Lake Estes (Olympus Dam) down through the upper canyon for stable tailwater flows.
Avoid:
High-elevation meadow stretches in the Park where the drought has left the channel painfully thin.
Key Fly:
FL CDL Nymph (#18-22) or Attractors such as Worms and Eggs
Flow Note:
Recent bump to 71 CFS has increased depth and velocity, making larger, flashier patterns much more effective.
Thursday, March 26th, 2026
The Big Thompson has just been given a much-needed shot in the arm with a flow bump to 71 CFS, a welcome departure from the stagnant winter trickles we’ve been seeing. While the extreme drought and record-breaking heat are still the overarching stories of the drainage, this extra push below the dam has revitalized the canyon’s pocket water. This is a prime opportunity that may not last given the lower upstream reservoir levels, so now is the time to hit it. The resident trout are fat and healthy from the early warmth, and the increased current has them looking for more substantial calories. This shift has put attractor flies back on the menu. An attractor lead fly like a Mop, Worm or Egg can be excellent for cutting through the new flow to grab a fish’s attention before your BWO trailer arrives. While still relevant in the mornings, Midges are officially taking a backseat as Blue Winged Olives are in full force during the afternoons. The fish are aware and cautious, but the increased surface chop from the 71 CFS release gives you just enough cover to get aggressive with your presentations. This sections is a great option while the flows hold.
CPW Station Details
Most Recent visit
Friday, January 9th, 2026
Today was one of my all-time best days on the Big Thompson River. While the river is busy, there is plenty of fishable water to be found. Near the dam, I was able to find a few fish. Then I got squeezed out and headed down the canyon toward Drake. Thankfully so, as I ran into the largest Rainbow Trout I have ever caught on this section of the South Platte River. After catching a few fish, I encountered the big momma shown in the video. She decided to make my day by eating a size 14 Jigged Hare’s Ear. A favorite river and a favorite fly. Life is good!
Overview
Below you will find all you need to know for a successful outing to the Big Thompson River in Colorado. River characteristics, fishing tactic and seasonal details.
The River
The Big Thompson River holds a special place in my heart. It’s where I spent most of my time fly fishing as a child. I proposed to my wife in the upper reaches of the drainage. We were camped out one starry night. The river can be divided into three sections. The first section is the upper reaches within Moraine Park and Glacier Basin. It can be the busiest section. Both are part of Rocky Mountain National Park. The second section is the tailwater below Lake Estes. You will find the largest fish here but also the most pressure and the heaviest crowds (next to the park). The third and longest section is the part that rushes through the canyon towards the town of Loveland. The river offers a wide variety of water types. Including open cutback meandering meadows, the tailwater troths, and the canyon pocket water. This tributary of the South Platte River offers it all!
Seasons
It’s crucial to note. The fishing conditions on the Big Thompson river are highly dependent on the section. They also depend on the river flows. The upper stretch within RMNP offers a solid fishing season from late summer into the fall. However, the access within Moraine Park/Glacier Basin freezes over in winter. The river continues this pattern until the tailwater below Lake Estes. If flows are reasonable, the river remains open for the entire public access stretch below the dam. However, during low flows, anglers may only find a couple hundred yards of open water in the coldest season. The canyon is influenced by altitude, sunlight, and temperatures. It often surprises with sections of fishable water even in the fickle Colorado winters.
Fish
All types of trout can be found on the Big Thompson River. Up high, in Rocky Mountain National Park, expect to find Brookies, Rainbows, and Cuttbows. As you move below the dam, you will notice more Brown trout. Further down the canyon, they become the most prolific. The Brookies and Cuttys thin out, but the Rainbows can be found throughout.
Tactics
This is smaller water when compared to most of the rest of the South Platte drainage. In the park, with the open meadow and cut bank-style stream, I prefer to throw dries as much as possible. Dropper rigs are a great way to fish up there. If fishing the tailwater below Lake Estes, expect to get technical due to the regular pressure. As the river slams through the canyon, it becomes more of a freestone-style waterway. This means you can pick your poison. Dries, dry dropper or nymph your heart out.
Bugs
Like much of the South Platte River, the Big Thompson has plenty of Midges. In addition there is a good mixed bag of bugs that can be found throughout the year. The staple mayflies such as BWO and PMD. The summer Caddis hatches and some smaller Stoneflies. Sow bugs are great below the dam in small sizes. While you might night think to, be sure to hopper cuck in Moraine park if you make the visit.
Recommended Flies
Previous Reports
Tuesday, June 24th, 2025
The Big Thompson River has been one of the best options throughout the spring. It remains that way as we head into the summer. Over the last 20 days, the flows have remained extremely consistent coming out of Lake Estes. The tailwater has fished as great as ever. The canyon near and below Drake has surprised me with large fish. The only questionable section is the river flowing through Rocky Mountain National Park and Moraine Basin. With the current CFS of 165, runoff is still present. If you head into this area, consider fishing the small tributaries and put in a little hiking. This time of year, fish the way you want. If you aren’t seeing surface activity at the tailwater, fish nymphs. Higher in the meadows or down the canyon, dry droppers will be an excellent choice. If you see risers, cut the nymphs and headhunt with dries. Summertime bug activity, such as Yellow Sally’s and Caddis, can be a great starting point when considering bug activity.
Friday, June 6th, 2025
The Big Thompson River has been fishing exceptionally well lately! The river flows through the canyon have fluctuated a bit this past week, so it’s important to stay updated. Provided the flows don’t surge too drastically, the area along the South Platte River continues to be an excellent choice. The tailwater below Estes Park remains a solid fishing spot, and the upper sections are now accessible. Although flows slightly vary with the weather, they appear to be trending downwards for the moment. This period is ideal for using a dry dropper setup while fishing through the meadows of Moraine Park.
Saturday, February 8th, 2025
It took a while, but today sure turned out to be a great day. I arrived at the river late in the morning, as it was a cold winter. Starting in the canyon below Drake was rough. I saw one relatively large fish (for the water) that was seemingly sunbathing before disappearing into the bottom of a riffle where he could no longer be seen. I fished a 200-yard stretch before deciding to head to the dam. Although it was busy, by the time I arrived around 2 pm, most people were wrapping up. Finally, finding the proper water produced some happy fish. The Pig Sticker did its job as a searching pattern, putting a few in the net, including the largest of the day. All the other fish were happy to eat the CDC Emerger. A great day on a home tailwater!
Thursday, April 3rd, 2025
The Big T is looking good. Flows are on the rise. It looks like they did a small pulse release at the beginning of April. This tends to be a positive thing for the water way as it will help flush sediment as well as bugs and even help to expedite runoff. I would expect more cold weather in the next few days but that shouldn’t turn things off. Up by the dam the fishing will be as reliable as ever. While I haven’t been up since the beginning of January, satellite imagery from late last month shows the waterway starting to break free of its winter’s grasp. Snow in the forecast could mean some excellent Blue Wing Olive action. A light dry dropper could be a great tactic when hitting this water. Keep the flies small and look for feeding fish. Good luck out there! Let me know if you go.
Friday, January 10th, 2025
Rocky Mountain National Park is a no go until spring. Unless we get an unseasonable warm period but that is not likely. For now focus below the dam at Lake Estes. The water is flowing pretty low so expect things to be technical. These should be the happiest fish on the drainage right now. If you are fishing below drake, seek the best water you can find and cover water. Get out and fish!
Sunday, November 3rd, 2024
A traffic day on the water today. Chilly start, up near the tailwater section. After driving by and seeing the low water and crowds I decided to move into the canyon. I fished a few sections and had to avoid the Brown Trout that were bedding up. The low clear kept the fish somewhat spooky. Mid-day the fish moved higher in the water column and began eating emerges. I was able to fool a few fish on Rainbow warriors and Manhattan Midges. No luck on the larger attractors on this section.
Monday, July 22nd, 2024
Summertime is a great time to visit the Big T. If you can, I would recommend heading into Rocky Mountain National Park. Remember, it is a busy spot, and you may need to reserve an entry time through Estes Park. However, it can be worth it as the stream is in prime condition, and the meadow is a pleasure to fish. With a common herd of elk hanging around, the fishing is the icing on the cake when fishing the Big T in RMNP. Below the dam, there is a good bit of water. This should mean good fishing all the way through the canyon if you want to keep it more “local”.
Sunday, June 23rd, 2024
Runoff has hit is peak and the waterway is in good shape. Warm days and cool water thus far have kept fish active and feeding. Summer time bugs are in play. Break out your Caddis and Stonefly imitations. Hopper dropper all day!
Sunday, November 3rd, 2024
The Big Thompson is in great shape right now. The tailwater section is fairly low and clear so the fish can be pretty picky. Through the canyon fish are still active. Browns are pushed down onto gravel beds so keep an eye out. The mornings are cold finally, so take your time getting out there and let the water warm up a bit. Hopper droppers are still a great option on this section. If you choose to fish an indicator rig, don’t be surprised if a fish takes your indicator.