CRITICAL FIRE WEATHER CONDITIONS EXPECTED SUNDAY AND POSSIBLY MONDAY WITH GUSTY WINDS AND LOW RELATIVE HUMIDITY ACROSS NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA. .Gusty south to southwest winds will develop Sunday afternoon, especially over western South Dakota where winds will gust over 40 mph. Further west over the Black Hills area and northeast Wyoming, winds will be much lighter, but deeper mixing may allow for frequent gusts to 25 mph. RH will drop 15 percent or below Sunday afternoon, which will result in critical fire weather conditions. Poor RH recovery is expected Sunday night. A cold front will then cross the region early Monday morning, supporting gusty northwest winds through the day. Portions of western South Dakota may see gusts of over 50 mph. RH will may fall to below 20 percent Monday, especially over southwest to south central South Dakota, which may again produce critical fire weather conditions. The National Weather Service in Rapid City has issued a Red Flag Warning for gusty winds and low relative humidity, which is in effect from 10 AM to 9 PM MDT Sunday. * AFFECTED AREA. Fire Weather Zones 323 Northern Foot Hills, 324 Eastern Foot Hills and 327 Butte County Area. * WINDS. Southwest 10 to 15 mph with gusts up to 25 mph on Sunday. Northwest 25 to 35 with gusts up to 55 mph on Monday. * RELATIVE HUMIDITY. As low as 11 percent on Sunday. As low as 20 percent on Monday. * IMPACTS. The combination of gusty winds and low relative humidity would produce critical fire weather conditions.
