Mammatus?

[dave48]

I took these pictures during a thunderstorm, I dunno if anyone can help but are the bits on the bottom of the cloud mammatus or not, if not what causes the bubbles? thanks B)

[MP-R]

Great picture. That looks like a Whale's Mouth formation, very common before thunderstorms or big heavy downpours. Just out of interest, where and when was that picture taken?

[dave48]

I see you are also from the area and it was taken in fishponds, bristol on the evening of 29th may, I think it was a decent storm but I only caught the edge of it or it wasn't very developed yet. Saw 5 fork lightning bolts though.

[MP-R]

Ah right, that being the day when the thundery cell brought flooding chaos to Crewkerne and Yeovil and the likes. Well there was no thunder or lightning here unfortunately but there were some awesome cloud structured ahead of the rather murky downpour as you have showed here.

[dave48]

Have done some research into the whales mouth formation and I think you are spot on with that, thanks very much for your help.