It is quite obvious why not as many chineses lanterns were successfully deployed in the uk on news years eve.
It is all a matter of physics. Hot air raises, however the average temp across the uk at midnight was over 10 degrees c, this would mean the lanterns would really need an additional source of heat to help them raise above the already warm air. Also some areas were very damp which would waterlog the paper lantern, making them to heavy to rise.
Last year the temps were in the minus's hence they 'lifted' with ease.