A marked thunderstorm starting 1332Z with many c-g discharges, one or two quite close (about half a mile). More interestingly, the precipitation was mostly large snow pellets, up to 20 mm, quite lumpy and hard but certainly not hail. Outside it was like being pelted with white fudge. The total amount was not large but enough to almost completely whiten the short grass in my back garden. The temperature fell from 9°C to 6°C. The sky was yellowish (and still is) with haze and had a distinctly summery look but other factors soon gave the lie to that.
A combination of late March sunshine a cold pool (524 dam) must be what set it off. I notice that showers broke out widely over southern England and the Midlands from from about 10 a.m. onwards.
Do I call this snow? If so, that is 2 consecutive days in March with snow but none in "winter".

Tudor Hughes, Warlingham, NE Surrey, 556 ft.