Unusually isolated rain cloud in France

Scribbler · March 31, 2016

My brother, who lives in southwest France wrote to me the other day about a strange experience. So here’s his words and your thoughts will be appreciated.

“It was getting on for 7pm (on 30th March) when I drove home from town (Riberac) and still nicely light with some weak sun shining from the west (where else!) As I drove out of town I was heading west for five minutes and then turned 90° in a southerly direction directly towards home. (As I've often mentioned) I live literally on top of a hill which is surrounded by valleys and a very large flat agricultural area which spreads away towards the north and the west. Well, it was through this flat area that I was now travelling. At the moment there's very little growing in the fields but they have all been ploughed so it appears to be quite an immense area and you can see for miles.

At first I didn't notice but soon realised that, although the sky all around and down to the horizons was light with the sunlight reflecting on distant white clouds, overhead was the most enormous black cloud, miles bigger even than a Vogon Constructor Fleet ship, that seemed to be almost stationary. The sort of black that could not even reflect light back. I was so amazed by this sight that I actually stopped my van and just sat there marvelling at this 'object'. It had also started to rain, great big blobs of the stuff not at all like raindrops and that reminded me that Meteo France had very recently mentioned the possibility of 'orage' which is thunderstorm and possibly hail.

When I returned home I checked on the weather radar to see if there was any rain due. There wasn't and there was only one area of rain on the map which was more or less round and corresponded exactly with the cloud I had watched. So I pulled out on the radar and there wasn't another area of rain in France apart from along the North coast and a couple of small patches towards Paris.”

So what caused that small ‘blob’ of cloud and rain? It was divorced from all other things such as fronts, depressions or even hills. I guess that the low sun added to the depth and darkness of the cloud, by the way. Personally I suggest that it was a small eddy in the pressure that created a mini-depression but I’d be pleased to hear someone else’s thought – especially someone who knows about weather.

PS Sorry his screenshots come from another weather site!