Dr. William Gray's April 2005 Predictions

Want another early start to the season? Looks like we might have a subtropical cyclone on our hands...in the southern hemisphere.

http://moe.met.fsu.edu/cyclonephase/gfs/fcst/archive/05050306/10.html

Water temps are about 24-25 C in the vicinity of the storm, as with last year's "Catarina," but the upper level temperatures are likely cold enough to support some sort of development. The system currently is located near 32 S, 24 W, with it projected to sort of just spin in place. It is still attached to some sort of frontal-type boundary to the east, but the connection between the two has appeared to weaken a bit recently.

Satellite: http://weather.msfc.nasa.gov/GOES/goeseastfullir.html, click on the cyclone in the lower right.

I can't find my upper-air charts for the S. Atlantic, nor can I make them on the fly right now, but water vapor imagery shows a ridge just to the west. If the system can transition down to the surface, we might see something (likely subtropical). I'd like to take a look at the models if I had the time -- see what the temperature values are in that region, see what's going on at the surface in terms of vorticity (or as the Weather Channel is fond of calling it, spin), and see what the moisture is in the midlevels (though WV shows there to be some) -- but alas, I don't. I heard from someone that one of the agencies put out a satellite estimate (not the one available to the public on NOAA's SSD webpage) of ST2.5/2.5 on the system -- a healthy subtropical cyclone.

(Edit: the Dvorak classification is available on the webpage now -- http://www.ssd.noaa.gov/PS/TROP/positions.html -- listed in the top list as 90L, South Atlantic)

QuikSCAT imagery: http://manati.orbit.nesdis.noaa.gov/hires/, click on the ascending pass near 32 S, 24 W. Strong winds are found near the center, mainly 30-35kt. Winds are weak on the southeast side, likely a function of the previous frontal nature, but may fill in with time. Note that the current image I've got is near 0800 UTC today, or about 12 hours old.

(Edit: the latest descending pass caught it, too, showing a further disconnect from the trough that it was once associated with it. Click on the storm on the second image on the above page, instead of the first image, to see it. This later one is from 1900 UTC -- or about 3p ET.)

Probably just another interesting thing to look at, like the system a couple weeks back, and one out in the central Atlantic near 30 N now, but still...it's May, so it's better than nothing.

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