The day before the aircraft were grounded again this week the cloud cover was heavy, though with more than enough blue to make a sailor a pair of trousers.
The clouds were moving very, very slowly in a generally southern direction & I was watching the process of docking as I stood at the bus stop. To my surprise I saw one cloud actually reverse direction & start to move back north as it was being pulled into the much larger one coming from behind.
Helps you understand how difficult it must be to forecast the behaviour of these clouds of volcano dust & ashes
