Prepare for 4 seasons. It has a pretty temperate climate- not too hot or too cold. Summers are not too hot, but can feel a little muggy. The average low in the winter hovers just above freezing. The damp-type of cold can be quite penetrating, though, so layering will keep you warm.
It is very rainy, and randomly rains all the time, so a good waterproof coat and jacket are pretty important.
There is excellent shopping there, so most recommend purchasing any winter clothing there. They carry lots of coats and jackets and shoes and that are waterproof and great quality. You can also purchase suits and dresses there.
Also, have good quality, comfortable, and waterproof shoes. Dr. Martens are well liked as well as Blundstone boots for both Elders and Sisters.
Missionaries mostly use public transportation like buses and the tube, sometimes drive, and maybe (rarely) bike.
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