About 100 firefighters are battling a wildfire that broke out in a canyon northwest of Boulder.
U.S. Forest Service spokeswoman Jackie Crosthwait says air tankers and helicopters are expected to resume dropping fire retardant on Monday.
Fire officials have put 340 homeowners on standby to evacuate. No structures are immediately threatened by the fire.
Meanwhile, hot, windy weather in southern Colorado has caused a wildfire that's been burning since June 12 to spread. The Duckett fire grew by about 400 acres over the weekend but it's not threatening any homes. Most the growth has been in a steep, rugged terrain in the Sangre de Cristo Mountains.
That fire is burning on 7-square miles and is 80 percent contained.