This is a post on weather. I maybe should have headlined it "Pas de deux" rather than "M&A."
But then it would have risked disappointing the the ballet crowd, and they can be mean buggers.
From Gulf Coast News Now, September 25:
Dancing Hurricanes: What is the Fujiwhara effect?
When 2 hurricanes glide close to each other, they can spin around in a stormy duet
Tropical Storm Humberto is rumbling in the Atlantic. It's track may be influenced by a secondary system bubbling in near the Bahamas. The two may experience the Fujiwhara effect and enter a sort of tropical tango.
The Fujiwhara effect occurs when two spinning vortexes, like hurricanes or typhoons, rotate around a shared center. This cyclonic samba happens when two hurricanes pass close enough, usually between 350 to 850 miles, to influence each other's paths.
The tropical twirl is dependent on each storm's strength. Two storms of similar intensities can spin into each other and merge to create one system. Sometimes, they briefly rotate, only to be tossed in separate ways.
If one storm is significantly stronger than the other, the weaker system usually begins to orbit around the larger. This is similar to the way a planet orbits the sun. Often, the smaller storm will orbit closer and closer until it eventually crashes into the larger system....
....MUCH MORE
Here's the current set-up from the National Hurricane Center.
Hurricane Gabrielle seems to be bound-and-determined to Reconquista the Iberian Peninsula:
while to the west Humberto has just become a tropical storm on his way to possibly maturing into a cat 2 Hurricane. Even further west, Invest 94 is also forecast to develop into a tropical storm and it's those two who could go all Fujiwhara on us:
1. Central Caribbean Sea and Southwestern Atlantic (AL94):
A tropical wave is producing a large area of disorganized showers,
thunderstorms, and gusty winds across portions of the Dominican
Republic, and the Turks and Caicos Islands. An area of low pressure
is expected to form along the wave tonight or early Friday when it
moves near the southeast Bahamas. This low is expected to become
a tropical depression when it is in the vicinity of the central and
northwest Bahamas in a couple of days. Interests in the Dominican
Republic, Haiti, the Turks and Caicos Islands, and the Bahamas
should monitor the progress of this system as heavy rains and gusty
winds are likely across that region regardless of development.
Interests along the coast of the southeastern United States should
also monitor the progress of this system.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 7 days...high...90 percent.
I had a bad feeling posting September 10's "Well, Today Is The Statistical Peak Of The Atlantic Hurricane Season":
And we still haven't gotten around to posting on all the various forecasts. Maybe next week for the whole batch.
***
On the other hand, just posting this little bit of hubris will probably be the butterfly-flapping-its-wings necessary to trigger the first whole-hemisphere-category-7-North-and-South-Atlantic-cyclone.
Fifteen days later no Cat-7 but we shall see.
