Well, if you know you're pretty low on fuel, you are likely to pick an airport where the weather is good, rather than risking three more missed approaches at a closer one where the weather is probably also bad.
Of course, Manchester is also a Ryanair base. There are two Ryanair bases closer to Prestwick (Edinburgh and Newcastle), but maybe the weather was bad there too? If the fuel situation was so dire, questions might be asked during the investigation why they didn't pick a closer airport with good weather that wasn't a Ryanair base (if one existed), but ultimately it's the pilots' decision to fly a bit further to an airport they are familiar with, and second guessing them with the benefit of hindsight is probably not a good idea...
They made two attempts to land at Prestwick, then diverted to Edinburgh (which also had bad weather). After one attempt at Edinburgh, they then diverted to Manchester.
Well, if you know you're pretty low on fuel, you are likely to pick an airport where the weather is good, rather than risking three more missed approaches at a closer one where the weather is probably also bad.
Of course, Manchester is also a Ryanair base. There are two Ryanair bases closer to Prestwick (Edinburgh and Newcastle), but maybe the weather was bad there too? If the fuel situation was so dire, questions might be asked during the investigation why they didn't pick a closer airport with good weather that wasn't a Ryanair base (if one existed), but ultimately it's the pilots' decision to fly a bit further to an airport they are familiar with, and second guessing them with the benefit of hindsight is probably not a good idea...
They made two attempts to land at Prestwick, then diverted to Edinburgh (which also had bad weather). After one attempt at Edinburgh, they then diverted to Manchester.