Some lady in Boston had a 14 pounder recently. That’s some watermelon.
Centreline.
And currency. Dime and Quarter size hail is pretty common, though oddly I don’t recall ever hearing any described a nickel sized.
The standard in the past was an acre. Since no one farms anymore, the new description is a football field. It is familiar and easy to understand. Other countries use the same convenient descriptions.
Another explosive unit is the Mt St Helens.
Well some there is a form of football that is played on an oval, and one of the best known football fields in NZ is known as “the cauldron” …
So make of it what you will…
The Cauldron is Lang Park in Brisbane, a league ground.