Which is colder: spring or autumn?

In general neither. It really depends on where you are and also what you consider spring and fall. read more

Well, it depends on your location. But, around here where I live (New Jersey in the Northeastern United States), Autumn is, on average, cooler than Spring because it's getting ready for Winter. read more

There are some locations where spring is colder and some locations where autumn is colder. Lots of factors at play. Follow-up: Pulled up some climate data for Sydney Mar-Jun avg temp is about 17°C and Sep-Dec about 18.75°C so I would say Autumn is colder for you probably. read more