Can Hurricanes "Merge"??

[STexan]

Looking at Leslie and Michael in the Atlantic got me to wondering ...

Can 2 substantial hurricanes "merge"?

Have 2 hurricanes "merged"?

What would more than likely happen if 2 hurricanes merge (such as Leslie and Michael) in the N Atlantic?

 

[mikedeason]

Theoretically, they could merge but would probably undergo a period of mutual orbiting before that merger would take place (Fujiwhara interaction.) I can't say that I have ever seen two tropical cyclones of similar strength completely merge in the Atlantic basin but IIRC, during the 1995 season there was Fujiwhara interaction between not only two tropical cyclones but three. Usually, the end result is a kind of "survival" of the fittest" in which the weaker storm will continue to weaken from the subsidence around the stronger storm and dissipate before merging. Fujiwhara interaction is more prominent in the western Pacific, though still not common, and mergers have occurred.

 

[TrumanBoyer]

Fujiwhara Effect

If the storms are nearly the same size and/or strength, they will more likely orbit each other around a central point.

Sort of like two wheels turning in the same direction, they will bounce off each other if they touch.

Of course, since we are not dealing with solid objects, eddies will form in the areas where the two interact,
and no "bounce" occurs.

If one storm is much stronger and/or larger, they do sometimes merge, with the smaller/weaker circulation being
drawn in to the larger.

Astronomers have seen this happen numerous times on Jupiter, where the Great Red Spot eats smaller red spots.
(Mmmm.)

The interactions between 2 tropical lows is called the "Fujiwhara Effect".
Very interesting to read about. Try Googling it.

And Here is a link to a Youtube video of satellite animation of two typhoons interacting...
http://www.youtube.com/watch?v=5EP65hv9hlw&feature=related

You can get more examples, of both Mergers and Orbits,
if you go to Youtube and Search on "Fujiwhara".

Neat Topic. Glad you asked.

-T

 

[STexan]

Found this along the same lines. I've seen 2 and 3 tornados in close proximity but never have seen 2 "merge".

Watch video >

 

[rdale]

That's not really a merger as much as it is one getting killed by circ of larger TOR.

 

[mikedeason]

Here's a pretty good video showing the Fujiwhara interaction between typhoon Pat and Tropical Storm Ruth in the Westpac during the 1994 season.

Watch video >

 

[GPhillips]

Mike, That's actually the same video as linked in Truman's post. Pretty cool loops though.

 

[mikedeason]

Mike, That's actually the same video as linked in Truman's post. Pretty cool loops though.

Had I actually woke up and had a cup of coffee before posting that, I might have noticed! Oh well, just consider it reinforcement.

 

[TrumanBoyer]

More Reinforcement

Had I actually woke up and had a cup of coffee before posting that, I might have noticed! Oh well, just consider it reinforcement.

Well, Mike it seems I did the same thing to you yesterday.
I think we posted our notes on Fujiwhara at about the same time (you were first) !

Here's more reinforcement from TWC website today...

MICHAEL
- By contrast, Michael is tiny, symmetric and strong. Michael and Leslie will eventually do a dance near Newfoundland as the smaller former gets close to the larger latter.

Full Article... http://www.weather.com/newscenter/tropical/

I will buy you a beer if TWC uses the word Fujiwhara in the next week...

-Truman

 

[Joshua Nall]

I remember this happening in the Atlantic not too long ago. I am unaware of the location of the box with my old hurricane tracking charts or I would look through them and find the year. I believe they were both hurricanes when they started interacting and as one neared the other the weaker curved around the stronger and rather quickly died. 10 or 15 years ago maybe.