The Weather in Venice
I have been to Venice in March and in May. In May it was very pleasant, cool and bright. And I noticed no smell at all. I seem to have heard so much about the famous Venice reek.
In March - again no smell - hardly any tourists - and it was cold. Of course I come from Australia so it doesn't have to be very cold for me to think it is cold.
The first day was cold but clear - but as I was walking back to my hotel with my friend at about 9pm - amazed that all the shutters seem to be slamming down on the cafes and bars (this is obviously an early to bed early to rise city) I suddenly had the witch in my hip bite me that always means rain. And soon. I mentioned it to my friend and she glanced up at the ice cold stars twinkling and said - It is a starry night.
But the witch in my hip is never wrong and we woke to rain. It was almost sleet. Very miserable. Particularly as there do not tend to be overhangs on the buildings so one gets the full force.
So make sure you have a brolly. Which was fine when I was there because there were few people on the streets. So you weren't poking someone's eye out. I am so short in a crowd with an umbrella I am a perfect menace.

San Giorgio - the square on the lagoon.
Doge's Palace
Waiting for the next passengers.
Lista di Spagna