As the first event for Harvard Square’s seventh annual Winter Carnival, Boston’s Celtic Music Fest (passim.org/bcmfest) gets things off on the right foot with a lively lineup celebrating the area’s Scottish, Irish and Cape Breton-influenced music and dance scene. Presented by legendary folk venue Club Passim (refer to listing, page 27) on January 9 & 10, the first night features a concert of traditional and contemporary Celtic music at Passim, which later hosts Boston Urban Ceilidh, a Celtic-themed dance party. The next day is highlighted by “Dayfest,” consisting of not only family-friendly music and storytelling at Passim but also participatory events, including Scottish country dance lessons, at the First Parish Church (3 Church St., Cambridge) around the corner. The scene shifts back to Passim for the BCMFest Nightcap concert with the all-female Celtic band Long Time Courting and special guests.