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.
Summary
Maximum discharge along the river is currently at the reporting a streamflow rate of cfs. This is also the highest stage along the Grand Calumet River, with a gauge stage of ft at this location. This river is monitored from 1 different streamgauging stations along the Grand Calumet 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 |
|---|---|---|---|---|---|---|---|---|
|
Grand Calumet River At Industrial Hwy At Gary
USGS 04092677 |
369 cfs | 1.66 ft | 2.22 |
Seasonal Discharge Comparison
Maximum Streamflow Discharge
Streamflow Elevation Profile
The river has a long history of industrial pollution, which has led to its designation as one of the most polluted rivers in America. The hydrology of the river has been significantly altered by the construction of dams and reservoirs along its length, including the highly controversial Indiana Harbor and Ship Canal. These structures have been built in an effort to control the flow of the river, reduce flooding, and provide water for industrial and agricultural use. Despite its environmental challenges, the Grand Calumet River has some recreational uses, including fishing and boating. The river also supports some agriculture in the surrounding area, though the pollution levels in the river are a concern for farmers.