basically, what ever site you use they all get their info from met office.
I use the one on my yahoo page weather.com
i don't like the met office one, information overload

i am not that clever

the bbc one on page 400 sky is pretty good.
I look at my area on a 5 day forecast and then 24 hr breakdown in 3 hr segments.
i found over the yrs that weather forecasts are only 70% accurate at best and looking at 5 day forecasts is just a general idea of what might happen.
the only time these are right is when there is a ridge of high pressure, like last week in south east.
lee