Some good points so far.
As suggested a call to London Information and we can get the latest met reports at your destination, a/c reports of current conditions over the channel and a good idea of any problems talking to the French airfields.
If the worse should happen and you have problems a radio tuned to 124.6/124.75/125.47 will get a quick answer and appropriate action.
London Info, no radar but an information and help service for all pilots.
End of advert.