Vancouver´s weather is the best of the climates that you can find among all cities of Canada.
In winter the city of Vancouver is not usual that snows or rarely it can be, so that means there won´t be any problems of circulation on the public transports due the bad weather. But of course, it will be cold, there is no scape from that (around -5 and 10).
In Summer is hot as obvious, but I do not have the sensation of that insane hot, that you would be better at home until nightfall cames. Easily you can stay out in the shade very eased (even a bit cold for someone chilly like me), no suffocation and no sweat just for being on the street. For me is one of the best seasons to visit Vancouver and I think is the best to make outdoor activities.
In the summer nights you do not need to take a jumper and you feel very good and fresh to be honest (sometimes I have bring with me the jumper at night just in case, but in the end I do not use for nothing, just annoying).
In the day to day, almost always is cloudy and although I was here less than a year, I heard that it rains a lot here (even they called Raincouver to the city) and is one of the biggest problems of here, due people get mad about rain and says it does not deserve to live here because of it.
But to be honest, in the 3 months I have been here, I think they exaggerate a lot about the rain, I have used more or less the umbrella 9 times in those 3 months and I come from the north of Spain and I can say that there rains truly, not as in Vancouver and in comparison, Van is a desert talking about rain, but as I said, cloudy is a lot of times.
Dawns at 5-6 on the morning and nightfall at 22:00 (very late).