Northern lights in Montana: tonight’s chance

The Hi-Line and the open prairie

East of the Rocky Mountain Front, northern Montana is a wide, high plain with few towns and a northern horizon that runs uninterrupted into Alberta and Saskatchewan. For the aurora, that geometry is ideal. At the edge of a town's range the display sits low, and on the Hi-Line nothing stands in the way. Havre needs about Kp 5.0, which puts it within reach of the G1 storms that NOAA counts by the hundreds per solar cycle. Driving north from Great Falls toward the border buys about 0.6 Kp, and it takes the city lights out of the picture.

West of the divide

The western valleys are different country: Missoula, Kalispell and the Flathead sit among ranges that cut off part of the sky, and Pacific air brings more winter cloud than the plains receive. Kalispell's threshold, about Kp 5.6, is still among the better ones of the West, and Flathead Lake opens a long view north from its southern shore. The Missoula page looks at the valley and its inversions.

Glacier and the Rocky Mountain Front

Where the plains meet the mountains, from Browning to Augusta, the Front rises abruptly to the west and leaves the northern and eastern sky open. That edge is a good compromise for visitors to Glacier National Park: the park's own valleys are deep and their northern horizons often blocked, while the plains just east of the mountains keep a flat view toward Alberta. Wind is the usual companion there in winter, and clear, windy nights after a Chinook are common.

The south: Bozeman and Billings

In the southern half of the state the thresholds climb to Kp 6.4 in Bozeman and 6.3 in Billings. That is still lower than most cities at the same latitude in the East, because the magnetic pole sits north of the Canadian prairies. Billings, on the Yellowstone River with open rangeland to the north, is covered on the Billings page. For the plains to the east, see North Dakota; across the border, the Calgary page.