Rain is also not an issue but the British summer can be an issue. My BMW Rallye Suite handles most conditions well but its when the weather is hot, then the Gore-Tex liners have to be removed. Opening the vents this makes the suit cool on hot days.
During the last few days few have had frequent heavy rain showers intermittently during the hot days. Its in these conditions that biking can get difficult. Do I ride with the Gore-Tex liners in or out. In, and if I stop, then the lack of wind causes me to melt in the heat. Leave them out and if we get a shower I am going to get soaked to the skin and then cold when moving.
Still what ever the answer, a car even with air conditioning is a poor second to the fun on a bike even in this heat.