A number of Tuesday’s events take place outside, including the dressage qualification at Versailles and the BMX freestyle qualifiers at Place de la Concorde.
Spain also play Egypt in the men’s football in Bordeaux.
Signs at venues encouraged spectators to wear hats, stay hydrated and apply sunscreen.
Organisers have contingency plans for each sport and venue – some sports, for example, have a specific temperature threshold where play cannot continue if it goes above that.
More than 300 water fountains have been installed in the city and there will be access to shaded areas at venues.
“We should not have any major cancellations, but we will evaluate on a case-by-case basis,” Paris 2024 operations director Lambis Konstantinidis told BBC Sport on Tuesday.
“We will not put anybody at risk.”
A recent report by climate scientists and heat physiologists (who investigate the impact of heat stress on the human body) at the University of Portsmouth in the UK, said average temperatures in the French capital for the equivalent period in which the 2024 Olympics will be held have increased by 3.1C (5.6F) since 1924.
The Olympic village was originally designed to be free of air conditioning, but in light of concerns about heat, 2,500 temporary cooling units were fitted.
The men’s triathlon had been due to take place on Tuesday but was postponed after tests revealed the water quality was not clean enough for the swimming leg to take place.
Heavy rain on Friday and Saturday caused the water quality to decline and it could be further affected by the forecasted storms.