I don't know what the "filter category S3" means. A VLT 13.4% lens will not be suitable for riding in cloudy conditions. Cloudy can mean different things. If it is seriously overcast like it is when it snows, then you probably want a lens with at least 40% VLT.
If you are looking for a lens that will work in both sunny and cloudy conditions, then a good compromise might be ~30% VLT or so. You should realize that besides the weather conditions changing (clouds can move in and out), the sun changes position.
40% VLT probably won't be ideal for a clear day when the sun is right on the horizon reflecting off of the slopes right at your eyes at sun set. If you are only going to ride with one lens, then shoot for 25-40% VLT so that its not too dark if it starts snowing and you will still have some protection when it is bright out.
13.4% is for really really bright days