Typically when it starts reaching temperatures over the 90°F then you should start considering other options. Some people tolerate the heat much better than others too. If you know you are not one of those people then you should start to consider whether or not you will be able to keep yourself cool enough to enjoy the trip and consider the area that you are going to. If you will be somewhere that has plenty of shade, is by the water, or very breezy then the temperatures won’t feel as bad. Watch the weather and follow the heat index advisories because they can give you a better idea of what it will feel like. If it is humid and 95°F, then the heat index could be at 105°F. Being outside in that kind of weather can be detrimental if you don’t have any way of staying cool.