North River River Levels

× Red Flag Warning
Until 2025-12-19T17:00:00-07:00 • National Weather Service
...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, sustained 45-55 mph with gusts upwards of 85- 105 mph, are expected in the foothills of Larimer, Boulder and Jefferson Counties beginning early Friday morning. Relative humidity values are expected to drop into the low teens, possibly upper single digits. While Red Flag conditions, critical fire weather, are expected across a larger area in northern Colorado, the most extreme conditions are expected to be along Highway 93 from Jefferson County into Boulder County and along US-36 north of Boulder to the Larimer County line and westward. There will be a high potential for fast moving wildfires, should any new starts occur. Winds toward I-25 and eastward will be slower to develop, and also speeds will be considerably lighter. That said, gusts of 25- 40 mph are still expected to combine with very low humidity and cured grasses to support critical fire weather conditions. Such conditions may be a longer duration than usual, with potential for low humidity to extend well into the evening hours. * AFFECTED AREA...Fire Weather Zones 238, 240, 241, 242 and 243. * TIMING...From 10 AM this morning to midnight MST tonight. * WINDS...West 15 to 25 mph with gusts up to 60 mph possible west of I-25, and gusts to 40 mph possible along and east of I- 25. * RELATIVE HUMIDITY...As low as 12 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.