Northern Lights Tonight in London, England

London needs a strong storm for the aurora. The city's threshold is Kp 6.2, a level that arrives only in the biggest geomagnetic storms of a solar cycle, and even then the glow sits low in the north, behind the largest light dome in the country. Most aurora pictures taken in England during a big storm come from cameras: a long exposure picks up a pink or green band that the eye barely registers.

If a storm is under way and the forecast shows clear sky, your best chance inside the city is a high, open spot with nothing blocking the north. Hampstead Heath, around Parliament Hill, gives a wide view over the skyline, though the light dome of the center sits right in that direction. Blackheath and Greenwich Park are lower, and Epping Forest on the northeast edge cuts the glare from a few angles. None of these is dark. They simply give you a horizon.

For anything more than a camera trace, leave town. The Thames Valley and the Home Counties are bright in every direction, so people head to the South Downs or to the north Norfolk coast, where the sea gives a clean northern horizon. Check the clouds first: autumn and winter nights in southeast England are often overcast, and a storm that coincides with a clear night is the exception.