It might officially be autumn but it is way too early to put away your sunscreen. You don’t ever have to put away actually, because the sun’s harmful UV-light is ever present. Even the pale winter sun can cause serious UV damage, if your skin is unprotected. You might not get sunburns, but the UVA rays that causes your skin to age, will work its (unwanted) wonders.
Rule of thumb is to wear UV protection whenever you spend time in the sun. You might not need as high SPF in winter as in the high summer sun – SPF 15 or 30 is enough.
May the sun shine on and on!