Can you wear ear muffs, take them off just before walking in the door, and just put them in your coat pocket or purse? They fold up very small now. Gloves also in pocket or purse. I’m going to assume you are in an extremely cold city and have to walk far. For me if it is 30+ degrees I would not worry about covering my head if I was outside less than 20 minutes.
Tthis is a retail store right? I don’t know what Metro is. If it is a retail store first impressions mean a lot. But, having a coat on is fine if you are walking in from the cold. Stand tall, confident, and smile. Be ready to shake hands if one is extended to you, which means at least have your right glove off.
Is the store in a mall? Will you have time once inside to look at yourself in the mirror? Or you walk right in the store? It is best to have your face look as you would if you worked there, which included hat off I am assuming. If taking your hat off messes up your hair then I would assume you want a mirror check. If it doesn’t then you can just pull it off before you approach an employee, it is absolutely fine to pull it off in front of them once inside.
If they interview you on the spot they will possibly take you to the stock room or out to a seating area in the mall. You can remove your coat and lay it neatly next to you or on the back of the chair if they don’t offer to hang it up for you.