Rivermatics

USGS Streamgage 12359800

S F Flathead River ab Twin C near Hungry Horse, MT

S F Flathead River ab Twin C near Hungry Horse, MT is USGS streamgage 12359800 in Montana, monitoring river discharge in hydrologic subbasin 17010209. It sits on the S F Flathead River, alongside 1 other gauge Rivermatics tracks on the same river. It drains a watershed of about 1,159 square miles. Discharge records at this site go back to 1964. Typical flow runs near 2,107.9 cfs in July and 2,188.7 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
Montana
Drainage area
1,159 sq mi
Gauge elevation
3,582 ft
Subbasin (HUC-8)
17010209
Coordinates
47.9791, -113.56068
USGS site number
12359800
Records begin
1964-06-08 (62 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for S F Flathead River ab Twin C near Hungry Horse, MT. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.

Forecast daily mean discharge in cubic feet per second, by date
Date Low p10 Expected p50 High p90 Range
876 965 1,076
846 976 1,192
798 927 1,136
773 915 1,151
758 908 1,168
737 888 1,145
716 861 1,103
678 811 1,021
640 756 926
605 709 850
579 674 797
557 646 754
540 625 723
519 600 689

All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 62 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.

Historical monthly discharge percentiles in cubic feet per second
Month Low p10 Typical p50 High p90 Range
January 213.5 365.1 885.1
February 240.2 381 1,018.2
March 263.6 461.1 1,302.2
April 827.5 2,188.7 4,833
May 3,578.7 6,996.5 13,622.6
June 3,532 7,094 13,783.7
July 1,048.9 2,107.9 4,337.4
August 425.3 650.8 1,109.4
September 291.2 417.4 818.6
October 275.1 417.1 953
November 292 483.9 1,197.8
December 249 399.3 1,013.2

All values in cubic feet per second (cfs).

Common questions

When does S F Flathead River ab Twin C near Hungry Horse, MT normally run highest?
June, on the long-term record. The median daily flow that month is about 7,094 cfs, against 365.1 cfs in January, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for S F Flathead River ab Twin C near Hungry Horse, MT?
It depends on the month. In January, half of days historically fall near 365.1 cfs, with the middle 80% of days between 213.5 and 885.1 cfs. The month-by-month table on this page gives the full range.
How long has S F Flathead River ab Twin C near Hungry Horse, MT been measured?
Discharge records at USGS site 12359800 begin in 1964, about 62 years, covering roughly 5,815 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for S F Flathead River ab Twin C near Hungry Horse, MT?
Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
Where is S F Flathead River ab Twin C near Hungry Horse, MT?
The gauge sits at 47.9791, -113.56068, in Montana, in hydrologic subbasin 17010209, at an elevation of about 3,582 feet, draining roughly 1,159 square miles.
Can I use S F Flathead River ab Twin C near Hungry Horse, MT data for flood or safety decisions?
No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.

Upstream and downstream on the S F Flathead River

Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the S F Flathead River in full.

Other gauges in this subbasin