[Squarel]

The accuracy?

http://www.metoffice.gov.uk/about-us/who/accuracy/forecasts

There are local variations which mean for example, that if you live in the welsh valleys, someone on one side can be having sun, while on the other side (and in view) there is rain.

The met office does forecasts for a broad area, if you want hyperlocal, wunderground is where I go. The met office could also run forecasts for each london borough, but I doubt you or anyone else would sit through a hyperlocal forecast on the news.