&gt; Not to mention the composition or what might be below the snow.<p>I don&#x27;t feel like this is particularly harder than any of the other problems self-driving cars face. To achieve performance on par with human drivers simple need to do a couple of things (which are what I do when driving in snowy&#x2F;icey conditions):<p>1) Categorize current&#x2F;recent road appearance into groups.<p>2) Do tiny periodic break checks on each relevant group to determine the traction available in that group.<p>3) Trigger a new set break checks when conditions change (e.g. exterior temp changes, precipitation changes, traffic density changes or road-type changes such as exit ramp or bridge)<p>This road surface analysis combined with a bit of traffic analysis should also allow you to determine &#x27;emergent lanes&#x27; in snowy conditions.