As above. The car is also parked on a slope overnight. Have only just noticed it. Water level in coolant bottle is not affected, so assume heater matrix isn't at fault. My last car was 28 years old so if it's anything newfangled like air con you may have to draw me a picture.

Thanks guys.

There is a connection box under the windscreen wiper motor where wires pass between the engine bay and the car interior. There are two drains in the plenum chamber and if are blocked, water can leak through.

Thanks. Will look at this, along with a good clear out of the leaves. Any more offers...

While you are clearing out the leaves, undo the bottom couple of screws on the rear of the front wheel arch liners and remove the compost collection from in there too. Flush through with a watering can from above.

Definitely water, and not brake fluid from the clutch master cylinder?

If it were brake fluid, then I would expect the system to be almost dry, as only a small amount of fluid would just absorbed into the carpet/sound deadening material.

The other possibility is that it is the aircon drain, if the a/c was on prior to parking up and the draining pipework has been dislodged then I have heard of that leaking into the car. However my money is on the compost factory :-)

Here's hoping. The compost factory would be the cheaper option. Definitely not brake fluid, but thanks for all the advice.

And the far more likely option. But I always prefer to rule out the critical possibilities first.

aircon drain connection is passenger side, more likely its the bonnet release cable grommit, or perhaps the loom through bulkhead to fuse box housing.

This is all good info. I have a busy morning ahead.