Possible Clues:

• Member of a jazz band going west, motorway's blocked for the holiday
• 66-Across setting, briefly
• December festival
• Grand pocketed by jazz band member, returning for the holiday season
• St. Nick's day
• Mexicans ignore nice time to exchange presents
• High-airfare season, for short
• Big workday for Saint Nick
• Yuletide abbreviated
• Kiss while under mistletoe, primarily in this holiday season