The Official Chart: First Look, which airs on BBC Radio 1 today between 6pm – 7pm, offers a first glance of the Top 20 ahead of Friday’s Official Singles Chart Top 100. The chart is based on preliminary sales and early streaming reports.Mariah Carey’s All I Want For Christmas Is You is leading the charge on today’s Official Chart: First Look. The festive hit is currently just ahead of Wham’s Last Christmas (2), with only 1,300 chart sales between the two. Both tracks have famously stalled at Number 2 despite several close calls over the years, so there’s everything to play for this week.New for 2020, Jess Glynne’s cover of Donny Hathaway’s This Christmas flies up 25 places to Number 3 on the First Look. The song is exclusively available to listen and buy through Amazon as part of their Originals series. If it stays on track, this will be Jess’s 13th UK Top 10 song.The influx of festive songs into the Top 10 this week means current Number 1, Ariana Grande’s Positions drops to Number 7 – but with five days of this week’s chart race left there’s still time for the song to rise back to the top.Another Amazon Original, Justin Bieber’s take on Rockin’ Around The Christmas Tree is up 16 places to Number 5, set to become his 23rd Top 10 hit.Other songs rising into the Top 20 on this week’s First Look are: Merry Christmas Everyone – Shakin’ Stevens (14), Step Into Christmas – Elton John (8), Do They Know It’s Christmas – Band Aid (9), I Wish It Could Be Christmas Everyday – Wizzard (12), Driving Home For Christmas – Chris Rea (13), Merry Xmas Everybody – Slade (17), and One More Sleep – Leona Lewis (18).The final Official Chart Top 40 will be unveiled exclusively on BBC Radio 1’s Official Chart with Scott Mills this Friday from 4pm, with the full Official Singles Chart Top 100 published on OfficialCharts.com from 5.45pm.