Europe is sweltering through its most severe heatwave on record, with temperatures shattering all-time highs across the continent and the heat now shifting east towards the Balkans and Ukraine.
What's driving it
The heatwave is being sustained by what meteorologists call an omega block -- a weather pattern named for the Greek letter because of the shape it creates in the atmosphere. Hot, dry air from North Africa becomes trapped over a region as low-pressure systems on either side prevent it from moving away. The result is that temperatures have been pushed up to 18°C above their seasonal average. Europe is particularly exposed: only about 20% of European homes have air conditioning, and much of the continent's housing stock was built to retain heat rather than shed it.
This is also the second major heatwave to hit Europe in two months. The first began on 24 May, with temperatures 10-15°C higher than normal, causing several deaths.
The scale
