Red Flag Warning
2026-04-13T20:00:00-06:00

* AFFECTED AREA...Fire Weather Zones 214, 216, 238, 241, 242, 246 and 247. * TIMING...From 11 AM this morning to 8 PM MDT this evening. * WINDS...Southwest 10 to 20 mph with gusts around 30 mph. * RELATIVE HUMIDITY...As low as 10 percent. * IMPACTS...Conditions will be favorable for rapid fire spread. Avoid outdoor burning and any activity that may produce a spark and start a wildfire.

Musselshell River

Last Updated: April 13, 2026

Total streamflow across the Musselshell River was last observed at 108 cfs, and is expected to yield approximately 213 acre-ft of water today; about 6% of normal. River levels are low and may signify a drought. Average streamflow for this time of year is 1,918 cfs, with recent peaks last observed on 2011-06-10 when daily discharge volume was observed at 51,070 cfs.

Maximum discharge along the river is currently at the Musselshell River At Harlowton Mt reporting a streamflow rate of 80.8 cfs. This is also the highest stage along the Musselshell River, with a gauge stage of 2.97 ft at this location. This river is monitored from 6 different streamgauging stations along the Musselshell River, the highest being situated at an altitude of 4,668 ft, the Musselshell River Nr Martinsdale.

The Musselshell River is a tributary of the Missouri River that runs through Montana.


15-Day Long Term Forecast


River Details

Last Updated 2026-04-13
Discharge Volume 213 ACRE-FT
Streamflow 107.6 cfs
Past 24 Hours: -46.2 cfs (-30.04%)
Percent of Normal 5.61%
Maximum 51,070.0 cfs
2011-06-10
Seasonal Avg 1,918 cfs
       
River Streamflow Levels
Streamgauge Streamflow Gauge Stage 24hr Change (%) % Normal Minimum (cfs) Maximum (cfs) Air Temp Elevation
Musselshell River Nr Martinsdale
USGS 06119600
53 cfs 1.73 ft 27.51
Musselshell River At Harlowton Mt
USGS 06120500
81 cfs 2.97 ft 0
Musselshell River Ab Mud Cr Nr Shawmut Mt
USGS 06123030
13 cfs 2.56 ft 3.23
Musselshell River Near Roundup Mt
USGS 06126500
56 cfs 1.37 ft -2.09
Musselshell River At Musselshell Mt
USGS 06127500
49 cfs 2.02 ft 0
Musselshell River At Mosby Mt
USGS 06130500
54 cfs 2.84 ft -14.08
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile

The Musselshell River is a tributary of the Missouri River, 341.9 miles (550.2 km) long from its origins at the confluence of its North and South Forks near Martinsdale, Montana to its mouth on the Missouri River. It is located east of the Continental divide entirely within Montana in the United States. Counting its pre-confluence tributaries, it measures 425–500 miles (684–805 km) in length.It rises in several forks in the Crazy, Little Belt, and Castle mountains in central Montana. The main branch is formed by the confluence of the North Fork and South Fork in Meagher County, about 25 miles (40 km) east of White Sulphur Springs, Montana, just east of Martinsdale, north of Martinsdale Reservoir, and just west of Meagher County's border with Wheatland County. The North Fork flows south from the Little Belt Mountains through Bair Reservoir, then southeast. The South Fork flows northeast from the Crazy Mountains. From the confluence of these two waterways, the main branch flows roughly due east past Two Dot, Harlowton, and Roundup, then turns north just past Melstone, and continues to the UL Bend on the Missouri River at the beginning of Fort Peck Reservoir.The Musselshell River has also been known as: Cockkleshell River, Mahtush-ahzhah, Muscleshell River, Mustleshell River, Shell River. The Musselshell was entered by the Lewis and Clark Expedition on May 20, 1805 and named by them for the freshwater mussels lining the bank, noting in their journals that the Minnetare people had given the waterway a similar name. The Blackfeet, who hunted buffalo and prepared the meat for winter in the Musselshell area, called it the Dried Meat River.