Pouch PGI48L - Small area WSW of CV Islands - Code Yellow

[Shuriken]

A tiny but apparently closed LLC has developed convection west of the Cape Verde islands. (Interestingly, the LLC appears to have developed from an eddy in surface westerlies southwest of Hurricane Lisa rather than from an African wave.) 29C SSTs and shear seems to be light.

Time-sensitive: http://www.ssd.noaa.gov/goes/east/catl/flash-ir2.html

[AJC3]

A tiny but apparently closed LLC has developed convection west of the Cape Verde islands. (Interestingly, the LLC appears to have developed from an eddy in surface westerlies southwest of Hurricane Lisa rather than from an African wave.) 29C SSTs and shear seems to be light.

Time-sensitive: http://www.ssd.noaa.gov/goes/east/catl/flash-ir2.html

Nice find. Over the years, I've seen a number of these small swirls over the Altantic, and quite often they start to toot off convection when conditions are right. Generally, they're so small and susceptible to low level deformation, and shear at just about any level, that they dissipate pretty quickly. However, sometimes they can maintain themselves for a few days if conditions are just right, but generally don't amount to much at all.

There was actually a case a couple years ago where a small clockwise rotating eddy formed a little north of the equator. I posted about it here on the forum here...

viewtopic.php?f=31&t=101548

and it made it onto the CIMSS satellite blog (there are a couple nice time lapses) here...

http://cimss.ssec.wisc.edu/goes/blog/archives/675

[abajan]

Yes, I noticed it too but somehow I doubt it will amount to much.
Just a hunch.

[Shuriken]

When's the last time you heard of surface westerlies in September in a solid belt from 10N-15N/20W-50W? ....weird. It's like the trade-winds just shut off in a kind of "Atlantic El Nino".

(Meanwhile, Julia is still spinning away at the top-center of that shortwave URL in the last post.)

[srainhoutx]

It certainly has a spin to it. Perhaps this is Nicole?

[btangy]

I wouldn't have noticed it unless it was pointed out to me. This swirl is actually moving toward the E because the winds in the Main Development Region are westerly right now at low-levels! Is this really the Atlantic? After some straining of the eyes, it looks like the ECMWF wants to take this and gradually form something to the E of the Windward Islands. It's so small, so it's hard to say whether it can remain coherent over the extended range and grow. Something to definitely keep an eye on, if anything else for its unusual nature.

[colbroe]

http://www.nhc.noaa.gov/text/refresh/MI ... 1752.shtml?

"ATLANTIC OCEAN...
SURFACE RIDGING AROUND A 1022 MB BERMUDA HIGH CENTERED NEAR
34N59W DOMINATES THE SW ATLC. A FEW ISOLATED SHOWERS ARE ACROSS
THE FLORIDA PENINSULA...AND N OF HISPANIOLA AROUND AN UPPER
LEVEL LOW CENTERED OF HAITI. A WEAK 1013 MB LOW IS CENTERED NEAR
30N48W SUPPORTING A FEW ISOLATED SHOWERS WITHIN 60 NM OF THE
CENTER. A SECOND 1011 MB LOW IS CENTERED N OF THE ITCZ AXIS NEAR
12N34W ENHANCING SCATTERED SHOWERS/THUNDERSTORMS WITHIN 100 NM
OF THE CENTER. "

[Gustywind]

Something to keep an eye my friends don't forget that we're always in September any low can be suspicious...

[Shuriken]

It's had a continuous, persistent ball of convection for almost 24hrs now. It appears to be slightly larger than it was yesterday. Movement: stationary.

[Gustywind]

[Gustywind]

000
AXNT20 KNHC 261029
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN SEP 26 2010

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF
SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE
EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE
IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND
RADAR.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

ATLANTIC OCEAN...
A 1009 MB LOW IS ALSO OVER THE TROPICAL ATLANTIC NEAR 12N34W. SCATTERED
MODERATE CONVECTION IS WITHIN 60 NM OF THE CENTER.

$$
FORMOSA

[OURAGAN]

And we have PGI49 inside Africa, hurricane season is not over yet

[cycloneye]

PGI48L Track

http://www.met.nps.edu/~mtmontgo/PGI48L.html

[Aric Dunn]

pay close attention to 45W and 10-12 north over the next couple days... looks like the early stages of a low forming.

[btangy]

Here's my extended range discussion for PGI48L from the PREDICT weather discussion to be submitted today:

The global models continue to move PGI48L generally toward the west in the extended period from about 40W at day 3 to 55-60W at day 5. The UKMET, GFS, and the GFS ensemble do not develop PGI48L, although it should be kept in mind that the ensemble members are not resolving the small vortex of PGI48L initially. The GFS forecasts moderate deep layer vertical wind shear through the extended range. On the other hand, the ECMWF does begin to strengthen PGI48L after day 4 with Okubo-Weiss values rising to about 2 x 10^-9 s^-2 by day 5. Also, the ECMWF has rising total precipitable water values through the period along with lower values of vertical wind shear compared to the GFS. The ECMWF deterministic run has support from its ensemble as well. The NOGAPS continues to show PGI48L slowly developing and maintaining itself east of the Windward Islands.

[Aric Dunn]

Here's my extended range discussion for PGI48L from the PREDICT weather discussion to be submitted today:

The global models continue to move PGI48L generally toward the west in the extended period from about 40W at day 3 to 55-60W at day 5. The UKMET, GFS, and the GFS ensemble do not develop PGI48L, although it should be kept in mind that the ensemble members are not resolving the small vortex of PGI48L initially. The GFS forecasts moderate deep layer vertical wind shear through the extended range. On the other hand, the ECMWF does begin to strengthen PGI48L after day 4 with Okubo-Weiss values rising to about 2 x 10^-9 s^-2 by day 5. Also, the ECMWF has rising total precipitable water values through the period along with lower values of vertical wind shear compared to the GFS. The ECMWF deterministic run has support from its ensemble as well. The NOGAPS continues to show PGI48L slowly developing and maintaining itself east of the Windward Islands.

sounds good to me.... I dont see the vortex doing much maybe just aiding to the developing vorticity farther west near 45W atm.

[abajan]

Here's my extended range discussion for PGI48L from the PREDICT weather discussion to be submitted today:

... The NOGAPS continues to show PGI48L slowly developing and maintaining itself east of the Windward Islands.

This caused me to sit up and take notice because when last I checked, the waters there were practically boiling (around 31°C) and I remember thinking at the time that any cyclones traversing that area while it was in that state could spell trouble for islands downstream.

The preceding response to btangy’s post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For Official Information please refer to the NHC and NWS products.

[Gustywind]

[Pedro Fernández]

Let me share an image of that low in high resolution. This little system is like a pretty tropical depression in miniature It has a low circulation center and a quite decent convection to me (more evident at 18 UTC visible images)... And the convection has been active for more than 12 hours...



We are monitoring it from Spain in our forum.

[punkyg]

Are the steering currents still weak? cause this area, like Lisa was a few days ago, has been stationary.