40° F and Under Is Too Cold Ultimately, the answer comes down to your personal tolerance levels. But most pro winter campers agree that 40° F (4° C) is when things start to get uncomfortable. At 40° F, you’ll start to feel the chill.
How cold is too cold for survival?
At 91 F (33 C), you can experience amnesia. At 82 F (28 C) you can lose consciousness. Below 70 F (21 C), you are said to have profound hypothermia and death can occur, Sawka said.