One of the forecasts is for a location, the other for a wide area.
That would likely explain some of the difference in temperature.
Also, one of the forecasts uses a single word to represent the
weather over a period of time at a location. The other one uses
several sentences to try and communicate the weather over a period of
time.
I note that the rain in the forecast is not due till the end of the
night. So if you have to provide a description of the night's weather
in one word, which word should you use? Wet, to represent a small
interval of time right at the end of the forecast? Or dry, to
represent the other 11 hours of the night?

These are communication challenges that the MetO are very well aware
of, as they have been in this game for a long time. They do give
guidance on interpretation of forecasts too - and the emphasis of
that guidance is (and always has been) to use the human-written text
forecast. Location-based forecasts are there to use in addition, but
the MetO advise that you remain aware of their shortcomings.

--
Freddie
Bayston Hill
Shropshire
102m AMSL
http://www.hosiene.co.uk/weather/
https://twitter.com/#!/BaystonHillWx*for hourly reports*