The heatwave alert has been extended until Thursday, with temperatures set to climb as high as 37 degrees in some areas.
Isolated storms and showers are possible during the week, but forecasters warn any rain will be brief and the wider hot spell will hold.
Health authorities are urging residents to keep hydrating, avoid strenuous outdoor activity at peak hours and check on vulnerable neighbours.
Growing anger over World Cup red card
Fire damages trees in the Jardin Anglais
Cows sweltering in the heat
Lake Geneva nudists fight for their lake section
Holiday makers seek more than the sun
Heat kills more than the roads
