Scotland are in a strong position at the break following three first-half tries at Meggetland.
Thompson successfully converted and home supporters in a fair-sized crowd were jubilant as it brought an entertaining first half to a close.
Wales have conceded a third try before half-time with right-wing Rory McMichael leaping high to catch a pin-point cross-kick from Thompson to dab the ball down.
Wales have worked their way into the game through their forwards with Evans putting a second penalty over, this time from in front of the sticks, to trim the deficit to six points.
The visitors continue to eat in to Scotland's lead as Evans one again hits the three-pointer.
Wales hoping to close the gap on the home-side as they will look to use the weather conditions to their advantage in the second half.
Evans boots a long-range penalty against the wind. Great kick by the young general.
Penalty Wales. The visitors strike back as flyhalf Cai Evans converts from distance.
Captain Connor Boyle is sure leading by example for the home-side. It takes a few defenders to halt his powerful runs.
With a name like Kwagga it is no secret that the Number 8 is actually South-African born, but qualify to play for Scotland through his grandparents.