What’s that whistling through the winter air? Why, it’s the beautiful vocals of One Ounce Opera and LOLA’s yearly festive show. During their “annual nightcap,” these nonprofit cultural orgs offer a sweeping seasonal showcase delivered by 18 Austin-based and classically trained vocalists accompanied by two pianists. They’ll first fill the halls of the Butterfly Bar before heading into the theatre around 8:30pm for an even bigger performance. Tickets are on a sliding scale from $10-50, so everyone’s got a chance to enjoy this wonderful winter wassail. – James Scott