From the time our daughter was born we struggled with her low tolerance to extreme temperatures.
We had an easy time with her issues in the winter because we could just bundle her up in extra layers and limit her exposure to the out of doors.
She never went sledding or anything like that because she would only end up miserable within minutes. During the Summer, this was a bit more difficult. Most activities that take place during that time of year take place outside as people love to take advantage of the warmth and sunshine after being stuck indoors during the long cold winter. Birthday parties, cookouts, and days at the park are normal for most people. This was not the case when it came to our daughter. If the outside temperatures were above seventy five she needed to stay indoors for most of the day. We learned all the places in our area that were climate controlled to go and have fun. Her birthday is in late May so to avoid disaster we always planned an indoor party for her. We would rent a pool at a local hotel so she could have an indoor pool party, host the event at a local theater so she and her friends could hang out and see the latest show, and one time we even had a sleepover at the science museum so they could all see the star display and do crafts that were space related. I think that she and her friends always enjoyed these parties and we felt fortunate that there were so many kid friendly places in our area that kept her cool. As she got older she seemed to gravitate towards friends that shared her need to hang out in climate controlled places or do activities during the milder seasons that took place outside.