Hundreds of screaming Potter fans queued outside the studios in Leavesden, near Watford in Herts, where all the multimillion pound-grossing films based on JK Rowling's magical stories were shot.
Local boy Grint, who played Ron Weasley, said: "This is the most glamorous I've ever seen Watford."
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The Supreme Court is set to decide on whether disabled travellers are legally entitled to have priority use of wheelchair spaces on buses.
There will be some brightness, with the best of the sunshine towards the south and southeast where it will again be chilly.
It is hoped the 7,400-mile journey will become a cost-efficient and time-saving way of transporting trade between China and the UK.