Recent research gives some insight into the behaviour of cyclists when faced with bad weather. Not surprisingly, they prefer to ride when it's neither too hot nor too cold.
But even in the rain and cold, some cyclists aren't put off, although this can depend on the local climate and the infrastructure available to them. In the long run, rising temperatures and the effects of climate disruption could change the situation.
The most significant variable regarding bikeshare use is time of day, followed by precipitation level, according to a study published in the Journal of Transport Geography entitled, "How does weather affect bikeshare use?"