Luggage and bags: BIG.
Clothing/Shoes/Weather Gear: Lots of 'all weather' clothes. The weather is unpredictable. Even in the summer the nights can get cold. In the winter, make sure to pack snow boots, scarf, thick winter coat, comfortable driving gloves, and extra pairs of socks.
Toiletries and Medical Supplies: Lots of lotion because the cold dry weather will dry your skin out the first day you're there.
Miscellaneous: Ice scraper. Don't rely on defrost, you'll need an ice craper.