During the floods in Thailand in October 2010 (not the far worse floods last year) we were diverted through the mountains in wet conditions. A very sensible cop escorted us as a convoy of cars, trucks and buses at under 60kmh to make sure no-one went too fast on unfamiliar, streaming wet roads, and everyone got through. But it's a bit impractical in the UK where, due to budget cuts, there are now less than half the police patrol cars that there used to be.