not talking about hypothermia that is health threatening, rather mild hypothermia, that first affects judgement, before there are any outward symptoms.
I don't ride a scooter (my Kymco is a UTV) but I do ride a motorcycle, in winter, at normal traffic road speeds. when temps are below 20°f, I limit my top speed to 60 or less, doesn't take long for yer helmet to feel like a block of ice at higher speeds. I also use duct tape to seal anywhere there are air leaks, around my waist, wrists, etc. when you're going 60mph and it's zero, an air leak feels like a needle poking you, I wear Sorel boots with felt liners. While I do have an electric heated layer, I don't count on it, I've had electrical failures more than once, when I do, I turn off everything electrical I can, even unplug the headlamp, so the juice left in the battery can get me to safety, thankfully, never had an electrical failure in cold weather. A voltmeter is mandatory to monitor the condition of your charging system before an idiot light tells you too late that it has failed