Answer:
The question is generally broad, as there are many different breeds of dogs and cats so comparing the two and the many breeds that had gone through decades of adaptation and breeding makes this a difficult question to answer.
However,
Studies show that cats can tolerate more higher and intense temperatures.
An important note:
adaptation generally means to change oneself in order to survive with the external environment,
toleration is the ability to tolerate or handle the situation or in this case the environment.
Continuing the However
This study brings many stereotypes that all cats can handle the weather while all dogs can't, but then again there are many breeds of the two species.
Cats do have many strategies to keep cool, and they can obtain hyperthermia and illnesses relating to extreme heat.
Cats use the strategies such as conserving their energy, drinking water, constant self-grooming, and finding cooler places allow them to be more adaptative than dogs.
Cats also have an insulating process within their coats of fur which all dogs may not have (or some other breeds of cats).
In conclusion
Cats do have more adaptative properties than dogs, however, this varies from the amount of different breeds and how different the two species are.