Freeze Warning
2026-05-07T08:00:00-06:00

* WHAT...Sub-freezing temperatures of 22 to 28 degrees, coldest in low lying areas on the plains. * WHERE...All of the plains and I-25 Corridor in northeast and east central Colorado. * WHEN...From 8 PM this evening to 8 AM MDT Thursday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing.

Souhegan River

Last Updated: May 6, 2026

Total streamflow across the Souhegan River was last observed at 284 cfs, and is expected to yield approximately 563 acre-ft of water today; about 36% of normal. River levels are low and may signify a drought. Average streamflow for this time of year is 793 cfs, with recent peaks last observed on 2023-12-19 when daily discharge volume was observed at 6,040 cfs.

Maximum discharge along the river is currently at the Souhegan River At Merrimack reporting a streamflow rate of 197 cfs. However, the streamgauge with the highest stage along the river is the Souhegan River (Site Wlr-1) Near Milford with a gauge stage of 3.69 ft. This river is monitored from 2 different streamgauging stations along the Souhegan River, the highest being situated at an altitude of 275 ft, the Souhegan River (Site Wlr-1) Near Milford.

The Souhegan River is a 33-mile-long river in southern New Hampshire that flows from its headwaters in the town of New Ipswich to its confluence with the Merrimack River in the town of Merrimack.


15-Day Long Term Forecast


River Details

Last Updated 2026-05-05
Discharge Volume 563 ACRE-FT
Streamflow 283.8 cfs
Past 24 Hours: -73.2 cfs (-20.5%)
Percent of Normal 35.78%
Maximum 6,040.0 cfs
2023-12-19
Seasonal Avg 793 cfs
       
River Streamflow Levels
Streamgauge Streamflow Gauge Stage 24hr Change (%) % Normal Minimum (cfs) Maximum (cfs) Air Temp Elevation
Souhegan River (Site Wlr-1) Near Milford
USGS 01093852
87 cfs 3.69 ft -35.7
Souhegan River At Merrimack
USGS 01094000
197 cfs 3.05 ft -11.26
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile

The Souhegan River is a tributary of the Merrimack River in the northeastern United States. It is 33.8 miles (54.4 km) long with a drainage area of 171 sq mi (440 km2) and flows north and east through southern New Hampshire to the Merrimack River.
The river begins in New Ipswich, New Hampshire, at the junction of the river's South Branch and West Branch. Flowing northeast, it passes through the center of Greenville and descends through a narrow valley to Wilton, where it turns east. The river valley broadens below Wilton, and the river passes through the center of Milford, crosses the southern portion of Amherst, and enters the town of Merrimack. Shortly upstream of the town center, the river passes over Wildcat Falls, then crosses under the Everett Turnpike and U.S. Route 3 to reach the Merrimack River.
The river is used for water supplies, a small amount of hydropower, and recreation. There are 28 threatened or endangered species sharing the watershed with 35,000 people. It is part of the New Hampshire Rivers Management Protection Program.
It was one of two rivers studied by the New Hampshire Department of Environmental Services to reach data and recommendations about allowable "instream flow".