The National Weather Service in Cheyenne has issued a Red Flag Warning, which is in effect from 11 AM Saturday to 9 PM MDT Sunday. * AFFECTED AREA...Fire weather zone 417.Fire weather zone 418.Fire weather zone 419.Fire weather zone 423.Fire weather zone 424.Fire weather zone 428.Fire weather zone 429.Fire weather zone 430.Fire weather zone 431.Fire weather zone 432.Fire weather zone 433. * WIND...During the daytime hours, west to northwest winds from 15 to 25 mph with gusts up to 40 mph. Overnight, lighter variable winds of 5 to 10 mph. * HUMIDITY...Daytime minimum RH between 5 and 10 percent on Friday and on Saturday, and between 8 and 12 percent on Sunday. Overnight recoveries of 20 to 40 percent along and west of Interstate 25 and 40 to 60 percent in Niobrara, Goshen, and Eastern Laramie Counties. * ADDITIONAL DETAILS...Isolated dry lightning and gusty and erratic winds associated with high based thunderstorms will be possible Saturday and Sunday afternoon and evening. * IMPACTS...any fires that develop will likely spread rapidly. Outdoor burning is not recommended. A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior.