Forecasters warn of ‘particularly dangerous’ fire threat in Colorado and Wyoming with 100 mph wind gusts possible

Forecasters are using the most dire language possible to characterize an exceptionally dangerous fire threat in parts of Colorado and Wyoming’s foothills on Friday.“This is a Particularly Dangerous Situation that poses a significant threat to life and property in the event of a wildfire start,” the so-called PDS red flag warnings issued by the National Weather Service offices in Boulder, Colorado, and Cheyenne, Wyoming, said.It’s the first-ever PDS red flag warning issued in Colorado. The rare warnings are in effect for parts of the state’s foothills, including parts of Boulder and Jefferson counties, and Wyoming’s Laramie County.“Residents are urged to assemble an emergency supply kit and know their evacuation routes,” the warnings said. “In some cases, safe and timely evacuation may not be possible should a fire approach.”The alerts warn of extreme and erratic wildfire behavior, including rapid wildfire spread, for any wildfires that start in a combination of very strong winds, extremely dry air and near-record warmth.The winds will continuously blow at 45 to 55 mph with gusts that could top 100 mph, destructive on their own.Power poles along U.S. Highway 93 near Golden, Colorado, are snapped in half during a strong windstorm on Wednesday. Outages are lingering in Colorado as a new windstorm hits. - RJ Sangosti/MediaNews Group/The Denver Post/Getty ImagesA public safety power shutoff will go into effect Friday morning for nearly 70,000 XCEL energy customers in Colorado over fears the destructive winds could down power lines and start fires. Some residents are still without power due to a public safety power shutoff on Wednesday during another extreme windstorm.The Storm Prediction Center also upgraded its fire weather forecast for the area to Level 3 of 3, extremely critical for Friday, the most severe level.The extremely critical area is for more than 600,000 people, including those in Fort Collins and Boulder in Colorado and Cheyenne in Wyoming.Winds will be weaker in a Level 2 of 3 critical fire weather zone that spans much of the Interstate 25 corridor and adjacent foothills of Colorado, Wyoming and Nebraska, but very dry air and dry fuels could still allow fires to spread here quickly.Dry conditions could persist well into the evening, potentially extending the duration of dangerous fire weather conditions across the region.For more CNN news and newsletters create an account at CNN.com