The Naked Scientists

The Naked Scientists Forum

Author Topic: Why do hurricanes take the path they do?  (Read 6982 times)

Stephen Sjodin

  • Guest
Why do hurricanes take the path they do?
« on: 23/11/2010 14:30:03 »
Stephen Sjodin asked the Naked Scientists:
Hi Chris,

I have a question that I've written to the US National Hurricane Center in Florida about.  I never heard back.

It's common knowledge that hurricanes are only sustained over warm water.  Now if one looks at historical maps of hurricanes in the North Atlantic, they tend to cross straight across from Africa, then veer North and follow the Eastern seaboard of North America.

My question is, do hurricanes follow this path because the land is in the way, or has the land been carved out the way it is because hurricanes would tend to follow this path regardless of the presence of the land?  Perhaps it's a bit of both as the warm water currents follow the same path.


Stephen Sjodin (pronounced show-deen)
New Brunswick, Canada

What do you think?
« Last Edit: 23/11/2010 14:30:03 by _system »


Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11582
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
Why do hurricanes take the path they do?
« Reply #1 on: 03/12/2010 02:39:39 »
The Weather Channel's tropical weather expert Steve Lyons had this to say about why hurricanes move like they do.

“Non-tropical weather systems (low pressure areas, gales and storms) generally move from west to east while tropical cyclones (tropical depressions, tropical storms and hurricanes) generally move from east to west. The answer to this is simple, they each move with the "steering" current they are embedded in. The steering current basically pushes them along. In non-tropical areas steering winds blow from west to east and hence so to do weather systems. In tropical areas steering winds blow from east to west and hence so to do tropical weather systems. The boundary that separates steering from west to east from steering from east to west is the subtropical ridge of high pressure, typically located near 30 degrees north latitude (farther south in winter and farther north in summer). South of this ridge of high pressure we find "trade winds" (blowing from east to west), north of this high pressure ridge we find "westerlies" (blowing from west to east).

Frequently tropical cyclones will move generally toward the west but also move north of about 30 degrees north latitude. When this happens we see the cyclone "re-curve" and begin moving toward the east in the same direction as non-tropical weather systems do in those locations. After all, a steering current will move tropical and non-tropical weather systems about the same, if they are about the same depth.

Unfortunately the world is not so simple and we have changing winds and steering currents in the east-west direction as well as in the north-south direction. It is for this reason we see rather wild and highly varied tracks to tropical cyclones. Steering currents are constantly changing in speed and direction due to continuously varying atmospheric weather patterns.”

And I think they follow the warm water, in cold water they should die out as I understand it?

The Naked Scientists Forum

Why do hurricanes take the path they do?
« Reply #1 on: 03/12/2010 02:39:39 »


SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums