Red Flag Warning
2025-12-20T00:00:00-07:00

...THIS IS A PARTICULARLY DANGEROUS SITUATION FOR IN AND IMMEDIATELY ADJACENT TO THE FOOTHILLS, BETWEEN 5500 AND 9000 FEET, FOR BOULDER AND JEFFERSON COUNTIES ON FRIDAY... Strong west winds of 30-40 mph with gusts as high as 85 mph in the foothills of Boulder and northern Jefferson Counties will continue until early evening. Relative humidity values had dropped into the upper single digits and lower teens. Thus, the Particularly Dangerous Situation will remain in place til around 5-6 pm, with only a slow improvement thereafter as winds slowly weaken. Red Flag conditions, however, will persist through the rest of the evening as we remain in a near record warm, dry, and windy airmass along the Front Range through midnight. In fact, strong, gusty winds will persist through much of the night with only a slow improvement in humidity values. Thus, near critical Red Flag conditions will occur into early Saturday morning. While most of the Denver metro area has seen lighter winds prevail most of the day, a period of strong, gusty winds is expected to develop this evening and likely last past midnight, producing Red Flag conditions there. * AFFECTED AREA...Fire Weather Zones 238, 240, 241, 242 and 243. * TIMING...Until midnight MST tonight. * WINDS...West 15 to 25 mph with gusts up to 50 mph. * RELATIVE HUMIDITY...As low as 9 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.


Sudbury River River Levels

Last Updated: December 19, 2025

The Sudbury River is a 32-mile-long river in Eastern Massachusetts that flows from its headwaters in Westborough through Sudbury, Wayland, and Concord before joining the Assabet River in Concord to form the Concord River.


Summary

Maximum discharge along the river is currently at the reporting a streamflow rate of cfs. This is also the highest stage along the Sudbury River, with a gauge stage of ft at this location. This river is monitored from 1 different streamgauging stations along the Sudbury River, the highest being situated at an altitude of ft, the .

       
River Streamflow Levels
Streamgauge Streamflow Gauge Stage 24hr Change (%) % Normal Minimum (cfs) Maximum (cfs) Air Temp Elevation
Sudbury River At Saxonville
USGS 01098530
57 cfs 4.81 ft 70.66
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile

The Sudbury River is a 32.7-mile-long (52.6 km) tributary of the Concord River in Middlesex County, Massachusetts, in the United States.Originating in the Cedar Swamp in Westborough, Massachusetts, near the boundary with Hopkinton, the Sudbury River meanders generally northeast, through Fairhaven Bay, and to its confluence with the Assabet River at Egg Rock in Concord, Massachusetts, to form the Concord River. It has a 162-square-mile (420 km2) drainage area. A 1775 map identifies the river by this name as passing through the town of Sudbury, itself established 1639.

On April 9, 1999, nearly 17 miles (27 km) of the river were "recognized for their outstanding ecology, history, scenery, recreation values, and place in American literature," by being designated as a part of the National Wild and Scenic Rivers System. The 14.9-mile (24.0 km) segment of the Sudbury River beginning at the Danforth Street Bridge in the town of Framingham, downstream to the Route 2 bridge in Concord, is designated as a Scenic River, and the 1.7-mile (2.7 km) segment from the Route 2 bridge downstream to its confluence with the Assabet River at Egg Rock is designated as a Recreational River, along with adjoining stretches of the Assabet and Concord rivers.Mercury contamination was discovered in the 1970s from the Nyanza plant in Ashland. The EPA subsequently listed the town as a toxic site and led a cleanup effort to repair the damage. It is still recommended that fish caught downriver not be eaten.