Northern Lights

The northern lights are a winter show, and live northern lights webcams point north to where it plays: Finnish and Swedish Lapland, the coast of northern Norway, Iceland, interior Alaska, the shores of Hudson Bay, and, on the strongest nights, as far south as Scotland, the Baltic and the northern United States. The aurora needs a dark sky, so the season runs from late August to early April; above the Arctic Circle the polar night brings darkness by mid-afternoon UTC, and the busiest hours are usually 21:00 to 02:00 local time. The Kp index, a 0 to 9 scale of geomagnetic activity, says how far south it reaches: a 3 lights up Lapland, a 5 reaches Scotland and the northern United States, a 7 has been seen from the Mediterranean. Cloud is the other half of the forecast, which is why several skies in several countries beat one, and a moonless night helps.