Why do the national weather forecasters keep giving forecasts for
Glastonbury after the music has begun?

It is pretty certain that few festival-goers will take time out from
viewing the main (or any other) stage in order to watch the national
weather forecast, and the people at home and sitting in front of their
TV are not going to be affected by the Glastonbury weather.

So, why bother?

…..and, yes I am an insufferable cynic.