7:05 p.m Edmonton,
I entered my lab. The sky was clear, the sun was bright. The light was too strong and I had to drop down blinders to block it out.

7:15 p.m Edmonton,
It's getting dark outside. I rolled up blinders. Oh my god~, just 10 minutes, the sun had been totally covered by clouds. A huge strom was attacking the city: lighting splited the sky, thunder sounds went through my thick glass window, and rains beated the whole building. But where did so many clouds come from? Amazing!

7:20 p.m Edmonton,
Seems my imagination still could not follow the weather here. Only after 5 minutes, the rain storm changed to the hail! Like thousnads of bullets, they dived from sky to the earth. Terrible.

7:35 p.m Edmonton,
What?? Sunshine?? Again? I was really really shocked to see the sunlight again and, the sky was totally clear. Everything was in peace. Like nothing happened before. How could that be! The whole process may even not be longger than half an hour.

This happened a few days ago. Now I am not so surprise about weather like this, because it happens a few times after that. Some friends told me they usually get this kind of stuff in summer.

I still remember that when I was in high school, my teacher told me people in English speaking country uauslly talked about weather for polite, but now I guess this reason may need to be updated. People talk about weather because it does change too fast, at least, in the summer of Edmonton.