Bit of help required here.

Got a new electronic barometer. Nothing hugely expensive. Anyway, I'm in
Donaghadee on the east coast of NI. The pressure reading on the barometer
is 1016mb and that seems to be close enough to the Met Office pressure
charts.

However... on the BBC site where it gives you a reading of "current nearest
observations" it says 1005mb. That's 23km away in Belfast, but is quite a
bit off the reading I have, which matches the Met Office chart.

Things were more or less the same yesterday but I thought I'd leave it 24
hours for my new barometer to settle down.

Am I missing something obvious?

There is a setting where I can offset the reading to correct it if
necessary...