Companies are reporting a drop in business, reflecting the economic toll of the heat wave, which is lowering productivity and keeping shoppers at bay.

PARIS -- Europe sizzled in its first major heat wave of the summer on Tuesday, as Barcelona recorded its hottest June in over a century and the summit of Paris’ iconic Eiffel Tower was closed to visitors.

Four people died in Spain, two in France and two in Italy as an early summer heatwave continued to grip much of Europe on Wednesday, triggering health alerts and forest fires and forcing the closure of a nuclear reactor at a Swiss power plant.