Michel D'Hooghe, the chairman of FIFA 's medical committee, will advise the executive committee that the risks of hundreds of thousands of supporters moving between venues in the extreme heat are too great.
The committee is now expected to agree in principle to move the World Cup to the winter, most likely in November/December 2022, and then embark on a six-month exercise to hammer out how it will affect the international calendar and the domestic leagues.
D'Hooghe's comments came as the United States' FIFA member Sunil Gulati said he was prepared to "rock the boat" and demand more time before making a decision.
But as the world governing body's medical chief, D'Hooghe's strong report favouring a move will make a significant impact.
D'Hooghe told Press Association Sport: "My position is very clear. From the medical point of view I think it will be better not to play during the hot summer months.
"I am sure the Qataris could organise it when they have such technical skill, and I know they could play and train in a stable, acceptable temperature.
"But the World Cup is more than about games and players - I have done eight World Cups so I know a bit about it.
"A World Cup is about the 32 delegations, it's about the whole FIFA family and the 12,000-15,000 media working very hard, and most importantly it's about the fans.
"They will need to travel from venue to venue and I think it's not a good idea for them to do that in temperatures of 47 degrees or more."
The European leagues have also asked for a delay in any decision in order to look at the impact the move would have on them - it will not be just one season as the 2021 Confederations Cup will also have to be in the winter, and there will be a knock-on effect to the seasons on either side.
D'Hooghe, however, believes those issues can be sorted out.
He added: "It's a technical question - I'm a medical man. I think we have nine years to sort it out.
"I respect the difficulties that there may be with some championships.
"I just have to give the medical advice and for the rest it would be a good thing to get everyone around the table to find a solution."
Gulati, who was the head of the USA 2022 bid that was defeated by Qatar in the vote three years ago, also raised the effect a winter tournament would have on other American sports.
He told the New York Times: "I don't see at this stage, frankly, how I or any member of FIFA's executive committee could make a sensible decision.
"We don't have enough information, and there are too many questions. I don't see how anybody in a position of responsibility can take a position without some answers.
"If the position I'm taking - which is that we need a lot more information - is rocking the boat, then I'm going to be rocking the boat."
He added: "There is another rather important sport that plays in the United States in the fall.
"How does a move affect us trying to promote the game if we're up against the NFL or college football now? That's a reality we have to consider. And it's just one of a hundred things like that which need to be considered."
- Sports & Recreation