A hailstorm, accompanied by thunder and lightning hit heavily trafficked Hellisheidi mountain pass between Reykjavík and Hveragerdi in southwest Iceland yesterday. The ground went white in a matter of minutes and at least one car slid off the road.
“There were very dark clouds in the sky when I was driving across Hellisheidi and then suddenly everything turned white and there was thunder and lighting,” Ingibjörg Bragadóttir, who had been driving on Hellisheidi with her daughter, described to Morgunbladid.
Police were called out to assist commuters. Snow is unusual at this time of year and all drivers have switched to summer tires. Thunder and lighting is even more seldom in Iceland. Lighting hit a power line causing a temporary blackout in Hveragerdi.
Meteorologist Teitur Arason explained that it had been unusually cold in the upper atmosphere yesterday and therefore the atmosphere over the country had been unstable.
When the sun heats the land it causes convection, creating high and padded thunderclouds. They are accompanied by thunder and lightning and sometimes hail, as happened yesterday.