The latest singing sensation to emerge from Wales has broken into the UK chart top 10 with her debut single.
Jem is hoping her new single 'They' will hit the top spot
Jem, who is from Penarth in south Wales, has already wowed audiences in the USA and her single 'They' went into the UK top 40 at number six on Sunday.
Named as America's biggest British female debut artist in 2004, she is now aiming for success in her home country.
She is hoping her song can emulate the triumph of the Grand Slam-winning Welsh rugby team.
Although now resident in Los Angeles, the singer had hoped to catch the game live.
Speaking before the match on Saturday, she said: "If I want to watch it live it will mean getting up at a ridiculous hour and going to an Irish bar to see it.
"I know that Steve Jones, the [Channel 4] presenter, is out here so I may hook up with him to watch the game.
"I am really tempted, but I may video it and ban anyone from telling me the result until I've seen it.
"I really wish I was I was there though."
As well as wishing for her home nation to take home the Grand Slam title on the weekend, Jem, 29, was also hoping that her debut single would hit a top 10 place.
"It is so exciting - I am just so pleased to be in competition with the likes of Elvis and Gwen Stefani," she said.
"I've been told that it should be in the top 10.
"I may be going on Radio One as well which is really exciting, but I am bit worried that if Wales win, I am going to have a hangover while I'm being interviewed," she laughed.
Jem is already an established name in America where her debut album Finally Woken has sold in excess of 200,000 copies.
She has even made a guest appearance on the American teen drama The OC and written a track for Madonna.
"It was just too crazy to comprehend," she said when she was asked how she felt about Madonna selecting her song.
"It was just so incredible."
Jem is wishing for a Welsh win as well as a top chart position
Jem, who was brought up in Penarth, decided on a career in singing at the age of 13 and pursued her interest while she was studying for a law degree at Sussex University in Brighton.
After graduating, she returned to Wales to record demos and then worked with producer Guy Sigsworth, who she wrote the song Nothing Fails with, which was used by Madonna on her American Life album.
Jem then travelled to America to work with various producers and songwriters, and her music was selected to be played on radio stations across the country.
"I've still got a lot of work to do in America but it is really exciting trying to make it in my home country as well," she said.
"I just feel so excited about it all."