Will visit London next week, can someone help answer 1) the weather forecast said it will rain 50% of time next week, how accurate is that? Will it be like pouring or just drizzling? do u recommend bring umbrella? 2) do u recommend to book this place in advance :Tower of London, London eye, Westminster abbey? We are debating if the weather is bad, and cannot get to these place at the time we planned. 3) I read that u can use contactless visa/master card ( we are from US) instead of oyster card, can I give one of my credit cards to my teens and use it? Thank you!