The finals were awarded to Qatar by world governing body FIFA in 2010 and are due to be held in the summer months when the temperature can reach more than 40 degrees Celsius.
In December and January the average is a far less intense 17 degrees.
Platini voted for Qatar to be awarded the world's top football tournament and was also in favour of Russia being awarded the event in 2018.
"I am in favour of Qatar under two conditions," the UEFA president told Bild newspaper. "Because of the heat the World Cup will need to be held in the winter. With over 40 degrees [Celsius] playing football is impossible and for the fans it would also be unbearable.
"Also, the neighbouring emirates must be included so that the World Cup is staged throughout the entire region," he added.
Saudi Arabia shares a border with Qatar while the United Arab Emirates is also very near, as is Bahrain, Oman and Kuwait.
Qatar's winning bid caused a major stir in world football with critics arguing it would be impossible to freeze football leagues to stage a World Cup in December or January.
They also questioned the choice of a tiny state that lacked the necessary existing infrastructure and enthusiasm to stage such an event.
"I was the only one who prior to the vote had said how he will vote. Both countries [Russia and Qatar] have never staged a World Cup," Platini said.
