Madison River Below Hebgen Lake Near Grayling Flow Report
As of July 16, 2026, Madison River Below Hebgen Lake Near Grayling is flowing at 1,090 cfs with a gage height of 1.93 ft, holding steady over the past 24 hours. Source: USGS gauge #06038500, refreshed throughout the day.
Historical Data
Madison River Below Hebgen Lake Near Grayling at a glance
How Madison River Below Hebgen Lake Near Grayling is running right now, where it sits on the map, and the key gauge stats.
Madison River Below Hebgen Lake Near Grayling is flowing at 1,090 cfs, with the water sitting 1.93 ft at the gage. Flow has held roughly steady over the past 24 hours.
This is USGS gauge #06038500 in Montana. Over the past 10 days the average has been 958 cfs, peaking at 1,130 cfs.
For real-time updates and historical context, see the realtime view or the historical comparison. Browse other gauges in the Montana flow report.
Engineering Data
Flow-duration statistics and observed peak-flow context computed from this gauge’s complete daily record (USGS #06038500).
Percentiles are flow-duration values computed from this gauge’s observed daily record as archived by Snoflo. Return periods are Weibull plotting-position estimates from observed annual maxima, provided as general reference context only. Always verify against official USGS NWIS records. Part of Snoflo for Engineering.
Streamflow Forecast
Over the next 5 days, Madison River Bl Hebgen Lake Nr Grayling Mt is expected to hold near today's 1090 cfs, toward roughly 1155 cfs by 2026-07-21 (likely range 951-1402 cfs) -- drier than normal for the date.
Powered by PULSE — Snoflo’s forecast engine, trained on this gauge’s full record of storms, snowmelt, and dry spells.
| Date | Expected (p50) | Likely range (p25–p75) | vs normal | Projected stage |
|---|
How does this compare to past years?
Year-over-year overlay, annual peak discharge, the full distribution of daily flows on record, and the gauge's rating curve.
Weather Forecast
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day forecast
Daily temperatures, snow, and rain projected over the next two weeks.
Madison River Below Hebgen Lake Near Grayling
The flow in the Madison River is primarily provided by snowmelt and precipitation. The river is affected by several dams and tributaries, including Hebgen Lake Dam and its associated tributaries. The river experiences seasonal trends, with peak flow occurring in late spring and early summer due to snowmelt. Interestingly, the Madison River was the location of a large earthquake in 1959, which created a landslide that blocked the river and formed Quake Lake. This event had a significant impact on the hydrology of the area and is still visible today.
Nearby streamflow levels
Cross-check Madison River Below Hebgen Lake Near Grayling's discharge against nearby gauges to spot whether the change here is local or regional.
| Gauge | Streamflow |
|---|---|
| Madison River Bl Hebgen Lake Nr Grayling Mt | 1,090 cfs |
| Madison River At Kirby Ranch Nr Cameron Mt | 1,320 cfs |
| Henrys Fork Nr Lake Id | 200 cfs |
| Madison River Near West Yellowstone Mt | 315 cfs |
| Red Rock Cr Ab Lakes Nr Lakeview Mt | 35 cfs |
| Big Springs At Big Springs Id | 128 cfs |
Nearby snowpack data
Snowpack at SNOTEL stations near Madison River Below Hebgen Lake Near Grayling. Spring snowmelt is the dominant driver of streamflow in mountain basins -- a deep snowpack upstream means more runoff later in the season.
| SNOTEL station | Snowpack |
|---|---|
| Nohrsc Beaver Creek | 0 in |
| Beaver Creek | 0 in |
| Carrot Basin | 0 in |
| Carrot Basin | 0 in |
| Tepee Creek | 0 in |
| West Yellowstone | 0 in |
River levels & flood safety
- Read the level before you go
- A river that's runnable at one flow can be deadly at another. Check current discharge and gage height — like the values shown above — against the flood-stage thresholds, and remember levels can spike fast after rain or a dam release.
- Respect cold water
- Snowmelt rivers run cold even in summer. Sudden immersion triggers cold-water shock and saps strength within minutes. Wear a PFD, dress for the water temperature (not the air), and never wade or paddle alone.
- Watch for swiftwater hazards
- Strainers (downed trees), undercut rocks, and low-head dams are the deadliest features on moving water. High, fast, muddy water hides them. If in doubt, scout from shore and portage.
- Mind flash floods & releases
- Narrow canyons can flood from a storm miles upstream, and dam-controlled reaches can rise without warning. Know the forecast, the release schedule, and your exit before you launch.
Track Madison River Below Hebgen Lake Near Grayling in the Snoflo app
Save this gauge as a favorite, set push alerts when streamflow crosses a threshold (e.g. "alert me when Madison River Below Hebgen Lake Near Grayling crosses 5,000 cfs"), and Snoflo's iOS app will push the moment USGS reports the crossing.
About Madison River Below Hebgen Lake Near Grayling
Where does the streamflow data for Madison River Below Hebgen Lake Near Grayling come from?
Discharge, gage height, and water temperature come directly from the USGS streamflow gauge 06038500. Snoflo refreshes the time series throughout the day. Forecasts come from the NOAA / yr.no feed Snoflo's iOS app uses.
How often is the report updated?
USGS gauges report continuously (typically every 15 minutes). Snoflo pulls fresh values throughout the day — look for the "as of" timestamp on the streamflow hero card.
What's the difference between discharge and gage height?
Discharge (cubic feet per second, or cfs) is the volume of water flowing past the gauge each second. Gage height is how high the water sits at the gauge (feet). They're related by a rating curve specific to each gauge — higher water means more flow, but the exact ratio depends on channel shape.
How is "percent of median" calculated?
Today's discharge is compared to the historical median discharge on this calendar day across the gauge's full record. 100% = right on median; 200% = a very high year; 30% = a drought-level low.
What are flood stages, and is this river safe right now?
Flood stages are NWS-defined gage-height thresholds — Action, Minor, Moderate, Major — marking when nearby roads or floodplains start to be affected. "Safe" depends on your activity and skill: a level that's a fun paddle for an expert can be lethal for a wader. Always check the current level against the thresholds above and the safety links, and when in doubt, stay off the water.
Can I get alerts when Madison River Below Hebgen Lake Near Grayling rises?
Yes — flow alerts are managed in the Snoflo iOS app. Favorite this gauge, set a streamflow threshold (e.g. "alert me when discharge crosses 5,000 cfs"), and you'll get a push the moment USGS reports the crossing.
Access the free Madison River Below Hebgen Lake Near Grayling report
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