Strange Patterns in the Sky (backblip)

I spent the day with my daughter......she makes me laugh..........I laughed so much my sides were aching and it quite wore me out  :-)

On the journey home I could see the sky in the distance looked very unusual......I thought it looked like misty mountains or large waves on a rough sea......I've never seen it look like this before.  The photo doesn't do it justice as it was taken through a side window of the car which was travelling at 90 70 miles an hour and there were only brief breaks in the tall hedges, but I think you can just about see the strange patterns.
About 20 minutes later the clouds caught up with us and deposited torrential rain along with lighting and thunder..........I was very pleased to get home without incident :-)