BIFL tier: 66 north, feathered friends, fjallraven, Canada goose, Carhartt Yukon extremes.

For those temps I think either a parka or layering a down puffer with a shell would be fine.

Warmest jacket would be something like the 66 north Jokla. But those are for really more for Arctic conditions, it's overkill for getting the mail in the Michigan suburbs.