We are getting the same treatment here in N.Wales dom. Thunder storm since very early with hailstones at about 7am, as you said the size of marbles. The weird thing is, as the hail is belting down almost vertically and the lightning is flashing, it is so warm and humid that it is disorientating. Plus this morning is bins and recycling collection day. So there I am with shorts and flip flops, a plastic pacamac, and an old sun hat belonging to "She who must be obeyed". When I had done I felt like a boil in the bag experiment.