It might be startling to realize this, but there's no particular reason to begin a new year on the first day of January. It's a week and a half past winter solstice, the shifting date on which the ancient Greeks rebooted their communal calendar, and nowhere near ancient Mesopotamians' preferred date, the vernal equinox. Pharaonic Egyptians celebrated their New Year's Day on the fall equinox, around Sept. 30. Indeed, it wasn't until the year 567, when Gallic bishops met at the second Council of Tours, that Jan. 1 gained traction as the new New Year's Day. Its status as such was finally cemented when the Gregorian calendar spread throughout Europe in the 17th and 18th centuries. Even American colonists observed March 25 as their New Year's holiday until the British switched over in 1752.  Moreover, the first of January has no great significance in Christianity; rather, it was chosen in honor of Janus, a pagan god with one face looking backward in time, another gazing forward to the world of tomorrow. New Year's Day is a bridge between history and potentiality.

It's only appropriate, therefore, that we convene the night before it as in days of auld lang syne (that's Scots for "old long past," courtesy of poet Robbie Burns) to toast each other and celebrate another elliptical loop around the sun. At Rhythm & Rye in Olympia, starting at 9 p.m., The Andy Coe Band will say farewell to 2019 with a psychedelic jam session rooted in jazz improvisation. "This will most likely sell out," warns club owner Andy Geertsen, "as his shows usually do for us." Coe, born in Seattle, has performed alongside Ravi Coltrane, Norah Jones, Duff McKagen and Jimmy Page. Bandmates Scott Goodwin, Chris Jones and Gary Palmer bring chops to match. "Oly loves Andy Coe in any form," Geertsen continues. "He's an old friend from my old booking days at the Eastside and has just gotten more and more popular since." A champagne toast is included with each guest admission. 

NEW YEAR'SEVE PARTY, 9 p.m., Dec. 31, Rhythm & Rye, 311 Capitol Way N., Olympia, $20, 360.705.0760

It's been 37 years since Prince first invited us to party "like it's 1999." The time since Y2K now exceeds the wait between His Purple Majesty's hit single and its foretold celebration. That song's a year older than Nicki Minaj, a full decade older than notorious partier Miley Cyrus. But hey, middle-aged readers, don't let that get you down! We can still have a "Totally Radical New Year's Eve" in the Emerald City. Sky View Observatory at Columbia Center opened in 1985, so that venue chose to celebrate the decade of 501s, mullets and neon Spandex. Says Free Rain manager and lead guitarist Dale Reinke, "We'll be playing dance music from all decades during the event. The special benefit, in addition to the music, is a bird's-eye view of the Space Needle fireworks."

TOTALLY RADICAL NEW YEAR'S, 9 p.m., Dec. 31, Sky View Observatory, 73rd floor, 700 Fourth Ave., Seattle, $150-$1250, 206.386.5564

The musical jams in Nisqually Red Wind Casino's Coho Sports Pub will be provided by Stir Crazy, with cash drawings of $2,020 culminating in a midnight balloon drop. Tacoma's Elks Temple location of McMenamins offers dance-party band The Main Squeeze. "This show is going to be so special," says Kathleen Tarrant, marketing manager for the Elks' Spanish Ballroom, "which we wanted it to be as our first holiday season in the Elks Temple. Expect a super-high-energy, fun party vibe all over the venue." Happy two-faced day, everybody!

2020 DANCE PARTY, 8 p.m., Tuesday, Dec. 31, Nisqually Red Wind Casino, 12819 Yelm Hwy. SE, Olympia, free, 360.412.5000

2020 NEW YEAR'S EVE CELEBRATION, 9 p.m., Dec. 31, Elks Temple, 565 Broadway, Tacoma, $35-$100, 253.300.8777, mcmenamins.com/elks-temple