Is it permissible to perform the obligatory prayer in the car when one is far from home and unable to enter the mosque due to high temperatures?

The legal rule is that obligations are conditioned upon ability, as Allah Almighty says: (Allah does not burden a soul beyond its capacity) and His saying: (So fear Allah as much as you are able). Muslims have agreed that if a worshipper is unable to perform some of the prayer's obligations, what they are unable to perform is waived, because the Lawgiver has, in many instances, treated the incapable as capable, in order to achieve ease and remove hardship.

Among the forms of facilitation is the permissibility of praying on a mount (such as a car) for whoever cannot dismount except with extreme difficulty, or fears that they will not find someone to help them mount again. It is obligatory for them to face the Qiblah; if this is not possible, they should direct the car towards it and then pray according to their ability.