Wade82/100
Wading is in play only where your chosen access has clear footing, legal entry, and no forced crossings.
All Colorado reports
Fly fishing report · West
Big Thompson
Is Big Thompson worth the trip today? Check flow, weather, hatches, access, and rules for Colorado before you go.
See the flow chart ↓Photo: Wusel007 Opens in a new tab. · CC BY-SA 3.0
Good day to fish?Latest river check
Good fishing
Yes. Fishing looks good.
82
Good fishing based on the verified flow and weather. No official live water-temperature reading is available. Carry a thermometer during warm weather and stop if the water is stressful for trout.
See update time and confidence
Live data checkHighHow much of the live flow, weather, and alert data came back.
Today's callMediumWater temperature not verified; do not use this score to clear warm-water risk.
Score calculated Aug 22, 2026, 10:24 PM MDTUsually checks again about every 45 minutes
Access choicesNo clear best mode
Wade and Bank / edge have the same top score. Use current access, footing, weather, and local rules to choose.
Bank / edge82/100
Bank and edge fishing remains a practical low-commitment option if access is legal and footing is safe.
FloatNot recommended
This report does not recommend floating this reach.
Your plan
Today's Big Thompson plan.
The Big Thompson fishes best when you match your reach to runoff, canyon safety, and the current Rocky Mountain National Park or Colorado special fishing rule section you actually plan to fish.
- Check first
- Use RiverReports for quick flow shape, then use USGS 06741510 as the official downstream flow check before committing to the canyon.
- Try
- Start with short, high-percentage pockets before you cast to long obvious runs.
- Leave when
- Skip during muddy runoff spikes, lightning-heavy afternoons, or when lower canyon water is warm enough to stress trout.
Live river check
What the river is doing
Check the latest flow and weather before you go. A quick change can make the river harder or less safe to fish.
Showing the latest stored river check while current readings load.
- Flow
- 66 cfs
- From the latest stored river check. Open the official source for the newest reading.
- Air now
- 64°F
Current NWS forecast period
- Next 24h high
- 82.0°F
NWS air forecast near
- Rain chance
- 37%
For this forecast period
This is an air forecast, not a river-temperature reading. Check the water with a stream thermometer before fishing in hot weather.
Latest stored weather check
Chance Showers And Thunderstorms
Chance Showers And Thunderstorms
- Wind
- 5 mph
- Weather checked
Recent flow chart is loading
The latest stored reading is shown above. Check the official source below if you need the newest value now.
More forecast and source details
National Weather Service
Big Thompson forecast point
The National Weather Service forecast is temporarily unavailable.
Live data
Where these readings come from
RiverReports gauge: Big Thompson
How to fish it
How to fish Big Thompson today.
Stable summer and early fall flows usually offer the cleanest all-day trout fishing. During runoff, target softer seams and shorter sessions, and when the canyon is rising fast, choose another Front Range option.
Low clear water
Fish early and late with smaller dries, light nymphs, and longer leaders.
Moderate stable flow
Best all-around pocket-water condition for dry-dropper coverage.
Runoff or storm color
Stay near soft banks and eddies, fish bigger nymphs or streamers, or wait for the drop.
Warm afternoons
Lower canyon water can warm quickly. Carry a thermometer and end the trout plan if temperatures climb.
Fishing words used on this page
- U.S. Geological Survey (USGS) gauge
- A USGS gauge is an official river station that measures flow or water height.
- Cubic feet per second (cfs)
- Cubic feet per second, or cfs, shows how much water passes the gauge each second.
- Nymph
- A nymph is a young water insect. Anglers also use the word for a fly that copies it.
- Seam
- A seam is the line where fast and slow water meet.
- Blue-winged olive (BWO)
- Blue-winged olives, or BWOs, are small mayflies that often hatch in cool or cloudy weather.
- Caddis
- Caddis are small water insects. The adults look a little like tiny moths.
- Dry-dropper
- A dry-dropper rig has a floating fly with an underwater fly tied below it.
- Emerger
- An emerger copies an insect as it rises from below the water toward the surface.
- Midge
- Midges are tiny flies and a common trout food, especially in cold water.
- Pale morning dun (PMD)
- Pale morning duns, or PMDs, are light-colored mayflies that often hatch in warmer months.
Why this call
Why this score
Short-term weatherUse caution
The forecast has storm or heavy-precipitation risk, so timing and access matter more than the score alone.
FlowHelps
USGS shows 66 cfs. The flow has been stable over about 6 hours. USGS marks this reading provisional and may revise it. USGS records for this date (1979-2025, 47 readings) show a typical middle range of 51 cfs to 75 cfs. Flow is within the typical range for this date, so weather, temperature, and access become the next checks.
SeasonHelps
Summer: Primary dry-dropper season, especially mornings in the canyon and park meadow water.
WeatherHelps
The current NWS air forecast is about 64F, and the next 24-hour high reaches about 82F. Chance Showers And Thunderstorms.
Public alertsHelps
No active NWS alert was returned for this forecast point.
Trip notes
Trip notes
Check these before you choose a reach.
Stable or dropping freestone flows with enough visibility to fish pockets and banks safely.
Skip during muddy runoff spikes, lightning-heavy afternoons, or when lower canyon water is warm enough to stress trout.
Base in Estes Park, check park rules and the lower gauge, then choose one upper reach and one canyon backup instead of trying to cover the entire river.
Shift to Boulder Creek, Clear Creek, or a South Platte option if runoff or canyon safety does not line up.
What to try
Big Thompson flies through the year.
Match the time of year, then let rising fish and current speed guide the next change.
SeasonWhat to look forFlies to try
Spring
What to look forMidges, BWOs, small stones, and caddis
SummerCurrent
What to look forPMDs, yellow sallies, caddis, ants, and beetles
Late summerCurrent
What to look forTerrestrials and evening caddis
Flies to try
Also try Hopper-dropper
Fall
What to look forBWOs, midges, and streamer windows
Each fly name opens its matching Fly Box guide.
Access and safety
Big Thompson access and rules.
Use these places as starting points. Open the access link below and check posted signs before you park or enter. Rocky Mountain National Park requires a Colorado fishing license for anglers 16 and older and lists specific catch-and-release and closed waters. Colorado's special fishing rule page also lists the Big Thompson from the base of Olympus Dam at Lake Estes downstream to Waltonia as artificial flies and lures only with immediate trout release.
Moraine Park
Classic Rocky Mountain National Park meadow water. Check current park access and section-by-section fishing rules first.
Lake Estes to Waltonia area
Special fishing rule canyon stretch with many short stops, but parking and shoulder safety decide which pullouts are worth fishing.
Lower canyon near Loveland
Best used as a short-session option when the upper river is too crowded or still dropping.
US 34 provides the basic canyon area, but do not assume every turnout is a comfortable or legal fishing stop.
Inside Rocky Mountain National Park, a Colorado fishing license is required for anglers 16 and older and park-specific gear restrictions still apply.
Treat canyon wading as a short-session plan with clear entry and exit points instead of forcing long walks beside traffic or steep banks.
River sources
Official Big Thompson sources.
Official agencies and primary river operators come first. Secondary tools are labeled so you know what carries the most weight.
How this report was checked
How this report was checked
Reviewed byBlueStreamFly River Review Team
Trip guidance checked
What was checked: This report uses official regulation, flow, weather, access, and public-land sources first, then adds practical planning guidance for fly anglers.
Live measurements and forecasts keep their provider timestamps. Rules, access, and trip guidance use the source-review date shown here. BlueStreamFly planning advice is editorial interpretation, not an agency notice.
First-hand experience: BlueStreamFly does not claim a first-hand visit or local field test for this report unless a real contributor is explicitly named and linked.
Rules and closures
Check what is allowed, where the rule applies, and whether the river is open.
Flow and weather
Check the latest river reading and forecast before you leave.
Access and land
Check public entry points, land rules, and seasonal access changes.
More helpful links
Use these links for stocking, safety, and other local details.
See all 7 checked sources
Rules and closures
Check what is allowed, where the rule applies, and whether the river is open.
What this source covers
Open the current rules and check the river section, season, and special limits.
What this source covers
Open the current rules and check the river section, season, and special limits.
Flow and weather
Check the latest river reading and forecast before you leave.
What this source covers
Open this page and check the latest safety advice before your trip.
What this source covers
Open this river reading to check the latest level, flow, and update time.
What this source covers
Open this river reading to check the latest level, flow, and update time.
Access and land
Check public entry points, land rules, and seasonal access changes.
What this source covers
Open the land or access page, then check signs before you park or enter.
More helpful links
Use these links for stocking, safety, and other local details.
What this source covers
Open this page and check the latest safety advice before your trip.
Quick answers
Quick Big Thompson answers.
Is the Big Thompson a wade river or a float river?
This page is primarily a wade plan. Most anglers do best by fishing short public sections rather than trying to float the canyon.
Which flow source should I trust first?
Use RiverReports for quick trend reading and USGS 06741510 for official context, then adjust for the specific reach because upper park water can look different from the lower canyon.
What is the most important rule check?
Check both Rocky Mountain National Park fishing rules and Colorado's special fishing rule page if your day crosses the park boundary or the Lake Estes to Waltonia stretch.