Eastern Boulder County will be under a red flag warning amid “extremely critical fire weather conditions” on Tuesday, meaning high winds and low humidity.

The warning is set for 10 a.m. to 7 p.m. across Boulder County below 6,000 feet in elevation, according to a National Weather Service alert. Winds from 30 to 40 mph with gusts up to 65 mph are forecast, with relative humidity as low as 10%, according to NWS.

The weather service warns that weather conditions could promote rapid fire spread, and it recommends that people avoid any outdoor burning or other activities that might make sparks. Open burning and agricultural burning is prohibited under Stage 1 burn restrictions across Boulder County, according to the Boulder County Sheriff’s Office.