There was light rain outside and cold weather, all day long (49 °F/ 9 °C).
I believe it’s a brown-lipped snail (Cepaea nemoralis). It is one of the most common species of land snail in Europe, and has been introduced to North America. The ‘brown lip’ refers to the lip of the shell opening. There is considerable variety in the color shades and striping of the shells, determined by the dominant and recessive genes in the snail’s DNA.