ATL: INVEST 90L

[DanieleItalyRm]

For me evident warm core cyclone, convection not possible in the cold core cyclone center.
You remember Grace? moved over 22 - 16°C sea surface.

You remember unnamed January 2010?
http://www.youtube.com/watch?v=hYjzOawj ... r_embedded

or Invest92 Jun 2009?
http://forum.meteonetwork.it/meteorolog ... zorre.html

7 - 8 Marzo:








8 - 9 Marzo:





10 Marzo:

[HURAKAN]

For me evident warm core cyclone, convection not possible in the cold core cyclone center.

So, this polar low off the Norway coast doesn't have convection around its center? It's compact and has organized convection, but it's as non-tropical as it gets.

[DanieleItalyRm]

Polar Low did not have a cold core, or better, cold but more warm air surrounding. Polar Low occured on very high latitude, they are almost invisible in the infrared sat and they always have (as you notice your image), obvious clouds of cold air around much of the sector. In 90L present evident outflow band typical of tropical system. There are many details typical of a tropical or subtropical system that are absent in the polar low.
You remember, on rare occasions, an extratropical cyclone can transit into a subtropical or tropical cyclone (Tropical Transition).

[HURAKAN]

But the environment isn't favorable for development, if we were in August - October, maybe the story would be different. Reports from ships in the area and Madeira do not indicate that this system is tropical or subtropical. The SST, air temp and dew point are quite low for a tropical or subtropical system.

[DanieleItalyRm]

[HURAKAN]

Latest

[DanieleItalyRm]

Sorry but, for me, this is an clear example of tropical or subtropical system obtained from tropical transition (the dynamic and thermodynamic transformation of a extratropical low into subtropical or tropical cyclone, or more 'just to cold core cyclone into a warm core cyclone, also under 26°C sea surface).
The little close circulation, convection and radial cirrus by outflow is only typical of tropical system.

[cycloneye]

SSD Floater is up for 90L.

[KWT]

Whilst not textbook its looking increasingly subtropical right now. Its hard enough to get systems in this area upgraded in peak season and will probably be ignored...

If it keeps strengthening then it will be a candidate but I think the only chance it has is a post season inclusion...

Still a nice little tease!

[HURAKAN]

Satellite images is not enough, until I see evidence, ship and ground reports that show that this system has at least a shallow warm core, I will stand behind climatology and common sense and call this non-tropical.

[HURAKAN]

Funchal, Madeira ... chilly temps

[Vortex]

Always interesting to have an invest in March It won't be long...

[pepeavilenho]

until I see evidence, ship and ground reports that show that this system has at least a shallow warm core, I will stand behind climatology and common sense and call this non-tropical.

What do you think about this?

550hP

350hP

200hP

100hP

Microwave 89GHz

General vertical diagram

[charlesw]

BEGIN
NHC_ATCF
invest_al902011.invest
FSTDA
R
U
040
010
0000
201103111454
NONE
NOTIFY=ATRP
END
AL, 90, 2011031112, , BEST, 0, 328N, 167W, 35, 999, LO, 34, NEQ, 0, 0, 30, 0,

999 mb low pressure with winds of 35 knts

[CrazyC83]

So it would be Tropical Storm Arlene if they decide to name it. Unreal!

[DanieleItalyRm]

But the environment isn't favorable for development, if we were in August - October, maybe the story would be different. Reports from ships in the area and Madeira do not indicate that this system is tropical or subtropical. The SST, air temp and dew point are quite low for a tropical or subtropical system.

it is really too small and isolate to be studied as an ordinary tropical cyclone, you're denying a evidence, this is a evident warm core system.

So it would be Tropical Storm Arlene if they decide to name it. Unreal!

they (Nhc) do not want to name a system of the North east Atlantic, they are waiting for it to dissipate

[srainhoutx]

I'd be very cautious making such statements.

[Migle]

they (Nhc) do not want to name a system of the North east Atlantic, they are waiting for it to dissipate.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

There ya go But I do somewhat agree with you. It's going to take alot for them to even start thinking about naming it.

[pricetag56]

I think this year is going to be very bad especially for the us. with the record earthquake that just happened in japan the 2012 prediction doesnt seem that crazy.

[DanieleItalyRm]

Sorry but they would not have given a name Vince and Grace if they had not had pression to email.
We all we have seen many days Vince and Grace before they were followed to nhc.
For example, these two warm core systems as they followed to invest but never appointed (both over Canary Isalnds):
and this occured on Tenerife for not advise for the passage of unnamed 2010 storm.
http://www.youtube.com/watch?v=cLTFBcN- ... r_embedded



Now there is' no problem, after 4 days INVEST 90L is dissipating the next hours. No name.