east pacific Major Hurricane Raymond

[Coast]

Raymond on the way out in the next couple of days?

 

[Somerset Squall]

Very strong shear continues to affect Raymond. Winds are down to 40kts. Despite the shear, some impressively deep convection has been exploding northeast of the LLCC for most of the day. The LLC however, is becoming increasingly elongated as the shear is disrupting it. As Raymond moves northeast, sea temperatures decline, which will most likely mean an end to the deep convection, and therefore an end to Raymond.

[Vorticity0123]

Very strong shear continues to affect Raymond. Winds are down to 40kts. Despite the shear, some impressively deep convection has been exploding northeast of the LLCC for most of the day. The LLC however, is becoming increasingly elongated as the shear is disrupting it. As Raymond moves northeast, sea temperatures decline, which will most likely mean an end to the deep convection, and therefore an end to Raymond.

This is what has happened now. The LLCC is so stretched and poorly defined, coupled with the fact that there is no organized convection left near Raymond, that the NHC has issued its last advisory of the cyclone. This marks the end of a very interesting cyclone, with an unusual path and rapid intensity changes.

 

The unusual track of Raymond. The colour circles indicate the intensity of Raymond, with dark blue a TD, light blue a TS, and from white to red: Cat.1-Cat.5.

 

The rapid intensity changes of Raymond show the enormous capability, as well as the enormous vulnerability of TC's. It shows that a very delicate balance of conditions has to exist in order to get cyclones going, but once a perfect balance is there, those things can very rapidly gain big potential for large destruction.

 

For example, when Raymond was beginning to move westward, the NHC thought gradual strengthening was likely as conditions seemed to be favourable. And yet Raymond refused to intensify for a long time. And once it started intensifying, it did so again rapidly to a cat.2 hurricane.

 

This is one of the processes that I find really interesting about tropical cyclones.

 

To get back to the present: Raymond seemed to have succumbed the effects of high shear levels (about 40 knots) caused by an upper trough over California, as well as cool SSTS.

 

http://tropic.ssec.wisc.edu/real-time/storm.php?&basin=eastpac&sname=17E&invest=YES&zoom=4&img=1&vars=11111000000000000000000&loop=0

 

But there is something I don't understand of Raymond. Latest visible imagery shows a large line of (I think) Cirrus clouds parallel to and moving along the shear direction. (better seen in a loop, that can be found here: http://www.ssd.noaa.gov/PS/TROP/floaters/17E/flash-vis-long.html). How did these clouds actually develop? Is this some kind of boundary between two air masses, or does it have anything to do with a possible subtropical jet? (current jet stream composites show a small jet over Raymond and the cirrus clouds, but the cirrus clouds originated about 10 degrees south of the jet).

 

The current state of Raymond, with high cirrus clouds parallel and moving along the shear motion. The LLCC is not very defined on this image.

 

The jetstream pattern currently analyzed from the GFS model.

 

And finally, a beautiful image of Raymond at its second peak.

This satellite picture is from NASA satellite.

Thanks for your help!

 

Sources:

http://www.turbulenceforecast.com/jetstream.php

http://www.nhc.noaa.gov/?epac

http://tropic.ssec.wisc.edu/#

http://www.nasa.gov/content/goddard/raymond-eastern-pacific/#.UnEqvflLPcA (there is also a very nice blog about Raymond on this site)

Edited October 30, 2013 by Vorticity0123