Chicago electrical wires explode in impressive showers of sparks during cold spell

Electrical wires emit an impressive series of sparks in Chicago early Wednesday as the city goes through a severe cold spell.

Temperatures dropped past -21 degrees Celsius and have been projected to plummet further.

The city is in the throes of the polar vortex, which is causing the Chicago River to "steam". States of emergency have been declared in Midwestern Wisconsin, Michigan and Illinois.