When home supply is low, and demand is high, it is usually easier to sell. Fewer people sell their homes during the winter, making homes on the market even more desirable.
Many people relocate for work at the beginning of the year, so new people will be looking to move into the area. These new residents will bring serious offers to the table.
Also, with fewer open houses during the winter and fewer homes on the market, buyers looking for homes are often looking more seriously and will want to put in a great offer to secure the house for themselves.