Sömskar took part in junior races until 2009. Since 2009 she has mainly competed in the Scandinavian Cup . She ran her first World Cup race in December 2010 in Düsseldorf , which she finished with 20th place in the sprint. In January 2012 she achieved her first top ten placement in an individual World Cup race in Milan with ninth place in the sprint. She finished seventh in the sprint in December 2012 in Canmore . This is her best result in an individual World Cup race to date. In January 2013 she took third place in a team sprint in Liberec with Magdalena Pajala, her first and so far only podium in the World Cup. She finished the season in 52nd place in the overall World Cup ranking and 25th in the sprint ranking. In the Rollerski World Cup 2014 , she took four podium finishes, including one victory in the 10.4 km mountain run in Val di Fiemme and came second in the overall standings. In the summer of 2014, she finished second in the overall ranking of the Rollerski World Cup . In the summer of 2015 she took six wins in the Rollerski World Cup (including five individual victories) and thus won the overall Rollerski World Cup. At the Rollerski World Championships 2015 in Val di Fiemme she won the silver medal in the freestyle sprint and the gold medal in the 10 km mountain run and in the team sprint together with Marika Sundin . In the 2015/16 season she made nine points in the World Cup, including 30th place at the Nordic Opening in Ruka , and thus achieved 36th place in the overall World Cup and 19th place in the Sprint World Cup. Her best placement of the season was fourth place in the sprint in Toblach . At the 2017 Rollerski World Championships in Sollefteå , she won the bronze medal in the sprint and the gold medal in the 18 km freestyle, in the 16 km mass start race and together with Maja Dahlqvist in the team sprint. In the 2017/18 season she took 35th place in the Ruka Triple, 29th place in the Tour de Ski 2017/18 and 34th place in the World Cup final in Falun and thus reached 41st place in the overall World Cup. In the following season she won the Engelbrektsloppet classic over 60 km and came second in the Scandinavian Cup in Östersund over 10 km freestyle. In summer 2019 she won eight Rollerski World Cup . In addition, she achieved second place twice and third place once and thus achieved second place in the overall ranking. At the Rollerski World Championships in Madona in 2019 , she won the bronze medal over 10 km classic and the gold medal in the sprint, team sprint and mass start race over 15 km freestyle.
In the 2019/20 season, Sömskar and Evelina Settlin finished third in the team sprint in Dresden and came 21st on the ski tour. In addition, with five top ten placings, including two third and one second place, she finished second in the overall ranking of the Scandinavian Cup.
Sweden
Jõulumäe
Madona
Val di Fiemme
Oroslavje
Beijing