Roaring forties

the westerlies or roaring forties
the belt of extratropical cyclones.
The trade winds from both hemispheres converge towards the doldrums and a zone of low pressure, the equatorial trough, that girdles the earth.

of the world also see a wide variety of fast-changing weather as cold air masses from the poles and warm air masses from the tropics push up and down over them, sometimes alternating within hours of each other, especially in the roaring forties ...