Funnily enough I was just about to post the same weather site, which I use. You should also find on your local BBC Radio web site (weather ssection) a 5 day forecast which I have found to be reasonably reliable
I think they only go up to 5 days with any reasonable accuracy and another 5 days after that but those are very prone to change. It's virtually impossible to predict what hasn't even formed in the atmosphere yet, sadly! Do you need to know for something inparticular?
The weather is making me daft too. I didn't read your question properly.
Just out of interest though the BBC Devon site has a very experienced amateur forecaster who predicts the long term weather for each quarter year. Over the last 40 years he has been correct 85% of the time( and no it isn't done with mirrors, seaweed or cow pats).
This forecast is only applicable to the Devon area though but you may have a similar guy in other areas.