In terms of going to Vegas for a trip and wanting to walk around and go sightseeing but not wanting to be sweating or dealing with hot weather, which month would be best to visit?
April / May in the Spring
Late Sept to Mid October in the Fall
November starts to get chilly in the evenings.
For daytime, I would say now. I tend to like the weather all around in October and November for Vegas. I have never been to Vegas in December, January, or February though but I would imagine it is about the same during the day but much cooler at night.
I think now is perfect. I would say September/October/November because they are cooler months without being too cold at night. Perfect for walking around and enjoying the strip at night.
From what I have read, the best times to go in terms of weather are March, April, September, and October. This is because it isn't overly hot during the day or overly cold at night.