I disagree with the general advice - I would try to do at least some hour-building in the UK, if that is where you will be looking for a job.
I'm all for doing some training abroad - but you've already done your PPL in the US. At some point, you really need to get at least a little bit of UK experience, even if it means putting up with some weather delays.
As for the weather - the best flying days in the UK are always in the winter, when the air is clear. Sometimes it takes a bit of patience waiting for these days, but it's worth waiting.
Maybe you could split your hour-building, so that you can do some where the weather is better, and some in the UK?
FFF
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