The beginning of daylight saving, which took effect early on Sunday morning, also marks the start of early UV sun warnings.
People should have moved their clocks forward by one hour overnight.
Spring temperatures may be low but Wayde Beckman of the health campaign Sunsmart says the power of the sun cannot be underestimated.
The weather doesn't have to be hot for people to be affected, he says. Peak ultraviolet ray periods generally fall between September and April.
A law change made in 2007 requires daylight saving to begin on the last Sunday in September and end at 3am on the first Sunday in April.