For tropical cyclones we have carefully tracked every instance of them, and naming them as soon as they have reached a certain intensity... flying aircraft in to measure conditions... compiling databases... creating models... and putting great emphasis on improving predictions.

However, it seems like for extratropical cyclones we do less. People only recently started to name extratropical cyclones... there doesn't seem to be a database of them... and they're just not portrayed as being as concerning when you hear about them on the news, even though they can have comparable wind speeds and minimum pressure to many tropical cyclones.

Why is there this difference?


1 Answer 1


Extratropical cyclones are relatively well understood. They often follow the Norwegian Cyclone model, which was developed in the 1910's and 1920's. Because of their spatial extent, extratropical cyclones are often less intense than their tropical counterparts. Since they are so much larger and live longer over land, it is easy to get data about an extratropical cyclone.

Tropical cyclones, on the other hand, have faster winds and affect people in a more dramatic fashion. If an extratropical cyclone is announced in winter, a grocery store may run out of bread. If a tropical cyclone is announced, there may not be a clerk available to restock the shelves. Tropical cyclones often don't live very long over land and are smaller, so it is hard to get data about them. Because they are smaller and the wind speed change over distance is so much greater in extratropical cyclones than tropical cyclones, errors in the forecast tend to have more of a dramatic effect on tropical cyclones.

To summarize:

  • Extratropical cyclones are often less intense.
  • We have an abundance of data on extratropical cyclones.
  • The theory behind the development of extratropical cyclones is longstanding and generally well established.
  • Tropical cyclones are much more dramatic and concentrated.
  • Forecast errors impact tropical cyclones more severely than extratropical cyclones (i.e. less predictable).

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.