Extratropical cyclones, sometimes called
mid-latitude cyclones or
wave cyclones, are a group of
cyclones defined as
synoptic scale low pressure weather systems that occur in the middle latitudes of the Earth (outside the
tropics) not having
tropical characteristics, and are connected with
fronts and horizontal
gradients in
temperature and
dew point otherwise known as "baroclinic zones". Extratropical cyclones are the everyday phenomena which, along with
anticyclones, drive the weather over much of the Earth, producing anything from cloudiness and mild
showers to heavy gales and
thunderstorms.