Cool.

Does that work no matter how heavy the snowfall is, or is there a point at which it's no longer effective?

How fast do you think you'd go under those conditions? (Wet road but no ice, plenty of snow on your glasses, wiping at least every 1/4 to 1/2 mile.)

(BTW my glasses are a strong enough prescription I can't look over them, 36 F wouldn't be very cold unless there were a lot of snow melting on the back of my gloves .)