Bovine Weather Prediction

His knowledge of country lore was a little hazy, but he felt fairly sure that if the cows lay down, it meant rain. If they were standing it would probably be fine. These cows were taking it in turns to execute slow and solemn somersaults; and Tyler wondered what it presaged for the weather.

Gnu bucking and galloping (rbm-QP301M8-1887-702a~3)
Terry Pratchett and Neil Gaiman, Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch

What do you think?