Mysterious snowstorm

It was weird - when I walked on the street, there were no signs of snow blizzard. Then I went up to Galleria Riga rooftop and discovered myself in rather strong snowstorm. I took some shots and get back inside the mall because my camera became dangerously wet in few minutes. After a short moment I returned on the street and - believe it or not - there were no signs of blizzard anymore! It was almost like the blizzard is happening only on the rooftop level :) I even tried to prove such a irrational theory and looked at roofs from below - but still didn't saw anything of what could resemble a falling snow. I was too lazy to try to get back on the rooftop. So there are 2 possible explanations. First - I experienced very short blizzard which somehow happened only and exactly at that moment while I was on the roof; second - I just came into a parralel Universe when came on the roof and somewhere in the mall there was a portal. :D