Boulder County trails west of Colorado 93, Broadway and U.S. 36 are set to close at sunset Friday and remain closed through all of Saturday, as the county braces for another bought of high winds and extreme fire danger.

Boulder County Parks and Open Space is closing all trails and areas west of U.S. 36. The closure includes the Anne U. White Trail, Bald Mountain Scenic Area, Betasso Preserve, Boulder Canyon Trail, Caribou Ranch, Hall Ranch, Heil Valley Ranch, Mud Lake and Walker Ranch, according to a county release.

Boulder Open Space and Mountain Parks trails west of Colorado 93, Broadway and U.S. 36 will also close at sunset Friday, according to a city release. Flagstaff Road will close to nonresidential traffic.

Officials made the decision to close parks amid weather conditions that could be hazardous for hikers. Windy and dry conditions mean sparks can quickly develop into a fast-moving fire, and flying debris and downed trees present a safety concern.

“We need people to stay off all closed parts of the system to prevent injury, reduce the risk of ignition and to allow rangers and law enforcement to respond to other calls for service associated with this wind event,” said Nuria Rivera-Vandermyde, Boulder’s city manager.

The county will be under a red flag warning from 11 a.m. to 9 p.m. Saturday, according to the National Weather Service. Relative humidity is expected to reach as low as 10%, and winds are forecast to persist between 20 and 30 mph, with gusts up to 50 mph, according to NWS.

Starting Sunday, county rangers plan to check all closed open space areas and reopen parks if no immediate safety concerns are visible from parking areas. An interactive trail map will update as trails open. Updates will also be sent to trail alerts subscribers. To subscribe, go to bit.ly/4cHAyvj.

County officials are asking trail users to use extreme caution after trails reopen and to report fallen trees or safety issues to posinfo@bouldercounty.gov.

City and county trails also closed in December amid high winds and dry conditions.