A heavy hitter?

Clouds like this brute were common this summer, but there will be lots around in the autumn too. It goes without saying that you shorten down and kit up before it arrives. The question is, does it have your name on it or not? You can always tell if a squall is going to hit you by treating its extreme edges as if they were ships on potential collision headings. In other words, is it on a steady bearing?

‘One edge going ahead of you and one astern?’ It’s got your number.

‘Both edges going the same way?’ Safe.

‘One edge missing and the other on a steady bearing?’ Take a chance with the oilies, but stand by the reef tackle!