It is possible to see robins even in Michigan in the winter. Contrary to popular belief many robins do not migrate but gather in flocks in the woods where they are sheltered. In a more mild winter it is not unusual to see a robin or two before spring. Usually the first robins that are spotted in early spring are the ones that didn’t migrate but are just leaving the shelter of the woods and are staking out their nesting territory before all the others arrive.
Also, contrary to popular belief a robin’s diet is mostly made up of berries and not worms. Some bushes and trees hold their berries through the winter and there is plenty of food for the robins and other birds that eat them. Worms and insects are more readily available in the early spring which is when most people see robins eating. Worms and insects are a good source of protein which the robins need as they start nesting. Most baby birds, even those of seed eating birds, are fed worms, grubs, and insects by the parents until they leave the nest.
If you have a tree or bush that produces berries in your yard or neighborhood, watch for the robins to come eat the berries. They also love strawberries. In our yard they eat strawberries, blueberries, mulberries, red-osier dogwood berries, and wild black cherries. I love when the mulberries are ripe because it is fun to watch all the robins eating the berries.