Some comments: Valle Hovin is not a bandy rink, it is primarily a speed skating arena. Both World and European Championships have been held there in the past. Bislett is not a "fully-fledged" football stadium anymore. Rather it is primarily an athletics stadium where football is also played. Nadderud will be removed in two years time as a new football-only stadium is built adjacent to the old one. The athletics club is moving to another location in Bærum municipality.
Lowest recorded temperature in Oslo city is −14.8 °F and highest 94.28 °F. So a pretty temperate place with no big extremes. Unlike Miami, probably the safest place to be in the world when it comes to future climate prospects.
Bislett stadium has been the sight of many Athletics world records, especially in middle and long distance. Cool summer air perfect for those events. Sebastian Coe broke the 800m and Steve Cram broke the mile records here in the 80s I think among many others. "The Bislett Games" is one of the biggest annual track meets in the world and its stadium is way bigger than that suburban one in the video you say is the biggest track meet stadium in Norway. FYI
