This is not an April Fool's joke - although it does seem like one: mathematicians are using crochet to predict weather patterns.
Hinke Osinga, a mathematician from the University of Bristol, realized that the equations which are used to model weather patterns could be physically represented in crochet:
"On the top part, the geometry is incredibly complex where you have a helical rotation going up and you have a spiralling rotation going in one of the opposite directions," Dr Osinga said.
While staring at the Lorenz manifold on computer, Dr Osinga had a brainwave.
"I realised the way that we computed the surface naturally translated into crochet instructions," she says.
"When I saw that, I just had to try. It was too good for words really that you could actually make one."
You can see read more about the work, see photos of other versions people have made, and get the crochet pattern here.
(The original crocheted work was created in 2004, but I just read about it today, via What's In The Making.)