Seven Red Flag Warnings are active across California, Montana, North Dakota, and Wyoming on Tuesday, with the National Weather Service flagging a notable eastward shift in critical fire weather conditions compared to the multi-state pattern that developed Monday.
The most expansive coverage is now across North Dakota, where warnings span more than two dozen counties stretching from the western badlands through the central plains and into the eastern Red River Valley corridor. The National Weather Service in Bismarck is warning that westerly winds of 20 to 30 mph — with gusts reaching 45 mph — combined with relative humidity values of 15 to 25 percent will produce critical fire weather conditions across western and central counties including Oliver, Foster, Stark, Morton, Burleigh, Kidder, Stutsman, Divide, Burke, Renville, Bottineau, Rolette, Williams, Mountrail, Ward, McHenry, Pierce, McKenzie, Dunn, Mercer, McLean, Sheridan, Wells, Golden Valley, and Billings. The trigger is a strengthening cold front pushing through the region.
The National Weather Service in Grand Forks has extended warning coverage further east, covering Pembina, Eastern and Western Walsh, Grand Forks, Griggs, Steele, Traill, Barnes, Cass, Towner, Cavalier, Benson, Ramsey, Eddy, and Nelson counties, with westerly winds of 20 to 30 mph and gusts to 45 mph. Relative humidity in those areas is forecast to drop as low as 20 percent. That warning runs from 11 a.m. through 9 p.m. CDT.
In Montana, the National Weather Service has issued a Red Flag Warning covering the Fort Peck Reservation and Daniels, Roosevelt, and Sheridan counties in the northeast, as well as Dawson, McCone, Prairie, Richland, and Wibaux counties — a corridor that aligns with the same frontal system driving the North Dakota alerts.
In Wyoming, warnings cover the Laramie Foothills and High Plains and the Laramie East High Plains. California’s active alert covers the Coachella Valley, where seasonal heat and low humidity continue to present elevated ignition risk. Residents near Palm Springs weather should monitor local conditions.
The National Weather Service emphasizes that Red Flag conditions mean any fire that ignites can spread rapidly and become difficult to control. The combination of strong winds, low relative humidity, and warm temperatures is the primary driver across all affected regions.
The cold front responsible for the Northern Plains alerts is expected to move through by Tuesday evening, but conditions warrant close attention through the afternoon peak heating hours. Residents across the affected counties in North Dakota, Montana, and Wyoming should avoid any outdoor burning. Those near Bismarck weather face some of the most acute conditions through the afternoon hours.