Surrey/Hampshire borders, it came down in stair rods.
I was at the local(ish) farm shop eight miles from home, the rain came through the roof of the farm shop in torrents, the car park was flooded, had to get into the back door of the car and climb into the front. I then drove home on a 50 road at just under 30, standing water everywhere, drains gurgling. I knew it was bad when the white van man behind me was hanging back and when I stuck my hazards on, (yes it was that deep in places) he mimicked me, at the top of Botany Hill the water was so deep, that I hit the standing water (slowly) and it attempted to go over my roof.
I drove a further two miles down the road and it had definitely been raining, but DH and DS were looking at me when I said how scary it was.
So in conclusion, I think it was localised and vicious.
Not something I wish to revisit for quite some time.