Sometimes the answer is "we just don't know"
In Britain most of the weather we get only develops in the last 2 or 3 days before it hits us. While it may be possible (sometimes) to say "there's a storm coming our way", or "some places will be windy" predicting exactly WHERE will be hit is probably outside the bounds of the knowable.
Even within 24 hours of an "event", the precise location - or worst hit spots - probably won't be evident until whatever it is actually starts to rain/blow/bake or blizzard all over it. if the Met Office was to buy some new sooper-dooper computers, would they really be able warn a particular village that it would be flooded, but the one 10 miles away wouldn't? Without that degree of certainty, we could end up in even worse bother: with the wrong emergency services being sent to the wrong place in advance of an imprecise prediction - instead of being held on "alert" until some calls for help actually came in.
Maybe what Britain needs is a bit more awareness (such as not building houses, or critical services, on flood plains or near rivers) having a few more gritters and the will to use them and for someone to be in charge, rather than diluting responsibility to a mess of small and poorly organised local councils who don't really have any incentive to take precautions against once-in-10-year weather events.