Synesthesia or salience: autism and environmental sensitivity

In the case of those of us most sensitive to environmental factors, is "weather (or whatever it is) salience" a more apt term to describe a higher degree of awareness that leaves other people wondering what on earth we are talking about and does synaesthesia sometimes get recruited by our neurodiverse brains as a means of extending the basic sensory tools so that we get to gather far more "data" from our environment in an attempt to better "systemise" our experience of the otherwise random-seeming world we live in?