Torrential downpours and hail on & off today. 

Lightning just recently been detected on the tail end of this current band moving through now.

Shelf cloud..

And a little mammatus seconds before hail struck..

I also spotted some lovely coiling of the scuds as the the band approached from the southwest but I was cycling on busy road so unable to stop.

Screen shot of most recent radar/ lightning curtesy of net weather radar..

I think that's because the trough or front producing the rain is also changing the airmass slightly. A NW'ly assault on hitherto SW ground.

as in the trough sucking up the relatively warm moisture laden Chanel air as fuel?