Rivermatics

USGS Streamgage 06428500

Belle Fourche River at Wy-Sd State Line

Belle Fourche River at Wy-Sd State Line is USGS streamgage 06428500 in South Dakota, monitoring river discharge in hydrologic subbasin 10120202. It sits on the Belle Fourche River, alongside 5 other gauges Rivermatics tracks on the same river. It drains a watershed of about 3,233 square miles. Discharge records at this site go back to 1946. Typical flow runs near 84.1 cfs in July and 92.2 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
South Dakota
Drainage area
3,233 sq mi
Gauge elevation
3,110 ft
Subbasin (HUC-8)
10120202
Coordinates
44.74889, -104.05111
USGS site number
06428500
Records begin
1946-12-01 (80 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Belle Fourche River at Wy-Sd State Line. 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
6.8 10.5 14.1
2.6 10.1 17.5
1.7 10 20.5
1.1 9.2 22.3
0.9 8 22.6
1 8.2 25.3
1 8.7 25
1 8.1 28
1 8.9 32.6
0.8 8.4 34.3
0.7 8.1 35.5
0.7 8.2 35.5
0.5 7.1 33.5
0.4 6.5 34.1

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 73 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 1.5 14.2 49.4
February 4.1 21.1 85.4
March 20.3 71.3 397.9
April 29.1 92.2 407.6
May 26.7 100 507.2
June 17.2 99.4 436.4
July 19.9 84.1 167.5
August 16.2 69.2 126.1
September 3.1 29.6 80.8
October 2.5 20.4 63
November 6.7 21.3 49.3
December 4.2 15.8 38.2

All values in cubic feet per second (cfs).

Common questions

When does Belle Fourche River at Wy-Sd State Line normally run highest?
May, on the long-term record. The median daily flow that month is about 100 cfs, against 14.2 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 Belle Fourche River at Wy-Sd State Line?
It depends on the month. In January, half of days historically fall near 14.2 cfs, with the middle 80% of days between 1.5 and 49.4 cfs. The month-by-month table on this page gives the full range.
How long has Belle Fourche River at Wy-Sd State Line been measured?
Discharge records at USGS site 06428500 begin in 1946, about 80 years, covering roughly 9,100 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Belle Fourche River at Wy-Sd State Line?
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 Belle Fourche River at Wy-Sd State Line?
The gauge sits at 44.74889, -104.05111, in South Dakota, in hydrologic subbasin 10120202, at an elevation of about 3,110 feet, draining roughly 3,233 square miles.
Can I use Belle Fourche River at Wy-Sd State Line 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 Belle Fourche River

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

Other gauges in this subbasin