Rivers in Montana

Boulder River at Big Timber

Sweet Grass County, MontanaNWS BTMM8USGS 06200000Billings office

Below flood stage
1.11ftStage

Observed Mon, Sep 21, 10:00 PM MDT

Flood stage
8.00 ft
Record crest
9.00 ft1997

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Minor flood8.00 ft
  1. 7.50 ftMinor flooding along the south bank.

Flood outlook

Chance of flooding, September to November

CategoryChance
Minor floodingUnder 5%
Moderate floodingUnder 5%
Major floodingUnder 5%

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued August 26, 2026.

Crest history

78 crests on NOAA’s list since 1947.

#DateStage
1June 5, 19979.00 ft
2June 13, 20228.56 ft
3June 1, 20208.33 ft
4July 8, 19758.25 ft
5June 30, 20118.04 ft
6July 5, 19757.89 ft
7June 18, 19747.87 ft
8May 28, 19567.84 ft
9May 29, 20147.71 ft
10June 15, 19597.68 ft
11May 27, 20187.64 ft
12June 7, 20197.60 ft
13June 12, 19917.60 ft
14June 23, 19717.60 ft
15June 27, 19707.58 ft
16June 16, 19657.51 ft
17June 28, 19647.50 ft
18June 10, 19967.47 ft
19June 29, 19827.44 ft
20June 6, 20217.44 ft
21June 20, 19687.43 ft
22June 10, 19787.39 ft
23June 5, 19487.37 ft
24June 6, 20177.26 ft
25June 2, 20157.17 ft

Most recent crests

  • June 11, 2024: 6.74 ft
  • June 3, 2023: 5.97 ft
  • June 13, 2022: 8.56 ft
  • June 6, 2021: 7.44 ft
  • June 1, 2020: 8.33 ft
  • June 7, 2019: 7.60 ft
  • May 27, 2018: 7.64 ft
  • June 6, 2017: 7.26 ft
  • June 10, 2016: 6.74 ft
  • June 2, 2015: 7.17 ft

Nearby

Upstream, downstream and the gauges around this one.

What this means

Forecasts by the Missouri Basin River Forecast Center. Forecasts are issued as needed during times of high water, but are not routinely available. Stage may be affected by ice during winter months. River forecasts will be issued for this location when the water level reaches 1.5 feet from flood stage.

Sources

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.