Another Little system over Canary Islands..

[DanieleItalyRm]

On 15-16-17-18 th (today) Jun a low system developed over Azores Islands from a big thunderstorm system:



15th jun 09:


16th jun 09:


On 17th the little low moved south-west, over the Canary Islands..

12:00


15:00


18:00


20:00


In the last night, the thunderstorm activity increase in the center.. it like a tropical depression, max winds 30 knots.

[DanieleItalyRm]

Today, 18th, continue the convection in the center..the storm moved on north-north east:

[brunota2003]

I highly doubt it is warm core though.

[HURAKAN]

It has a lot of work to do! But these systems are always interesting!

[DanieleItalyRm]

I highly doubt it is warm core though.

for me have warm core.. it's very little for European cart..
Not possible convection in the center if it is have cold core.

[Pedro Fernández]

I have known about this issue thank to a friend in our forum, from the Canary Islands (just that you can see in the image)........ Another interesting evolution of an old extratropical low pressure system.



I forgot it: date of the image: 17.06.09, 18 UTC.

[DanieleItalyRm]

18th, 15:00

[DanieleItalyRm]

[brunota2003]

From the 805 pm Atlantic Tropical Weather Discussion:

ATLANTIC OCEAN...
A DEEP LAYER CENTRAL ATLC TROUGH IS SUPPORTING A COLD FRONT THAT
ENTERS THE DISCUSSION AREA NEAR 32N52W AND EXTENDS W-SW TO 29N61W
CONTINUING AS A STATIONARY FRONT TO 31N70W AND AS A WARM FRONT FROM
THAT POINT INTO A 1013 MB LOW CENTERED NEAR 32N74W. A SURFACE TROUGH
EXTENDS S-SW FROM THE SURFACE LOW ALONG 30N75W 27N78W 26N80W AND
ACROSS EXTREME SRN FLORIDA INTO THE SE GULF OF MEXICO. ISOLATED
SHOWERS ACCOMPANY THE SURFACE TROUGH N OF 27N W OF 70W. ELSEWHERE...
SCATTERED SHOWERS ARE WITHIN 200 NM N OF THE STATIONARY FRONT
BETWEEN 55W-70W AND WITHIN 150 NM EITHER SIDE OF THE COLD FRONT
BETWEEN 45W-55W. ACROSS THE MAJORITY OF THE CENTRAL AND E ATLC A
BROAD SURFACE RIDGE DOMINATES ANCHORED BY A 1028 MB SURFACE HIGH N
OF THE DISCUSSION AREA NEAR 41N26W. HOWEVER...A DEEP LAYER LOW OVER
THE NE ATLC IS ASSOCIATED WITH A 1015 MB SURFACE LOW NW OF THE
CANARY ISLANDS NEAR 30N19W. LOW LEVEL CONVERGENCE NEAR THIS SURFACE
LOW IS SUPPORTING ISOLATED SHOWERS N OF 30N BETWEEN 17W-24W.

[DanieleItalyRm]

Like in structur as many tropical depression,with thunderstom activity little north-north east of the center:
Look Tropical Storm Ernesto 1-2-3 September 2000



And the Canary unnamed cyclone 15-16-17-18-19 Jun 2009:

[DanieleItalyRm]

on the 19th continue the little closed circulation with debol-moderate convection in the center and 30 knots winds:



day:


evening:

[senorpepr]

Definately NOT warm core. Actually, there's a marked cold pocket aloft at 500 hPa. This is creating a pretty steep lapse rate between this cold pocket and the (relatively) warm ocean surface. This steep lapse rate is allowing for convection to form.

[brunota2003]

Definately NOT warm core. Actually, there's a marked cold pocket aloft at 500 hPa. This is creating a pretty steep lapse rate between this cold pocket and the (relatively) warm ocean surface. This steep lapse rate is allowing for convection to form.

So does that mean the cold pocket is behaving similar to a cold front? The warm(ish) air close to the ocean's surface is trapped beneath the colder air as it advances, and then tries to rise up, creating the updrafts that lead to the storms? (warm air rises...I know that much xD)

[senorpepr]

Sort of. It's not really cold air advancing, but rather cold air "trapped" over the circulation.

[brunota2003]

Yes, but the whole circulation is advancing, and with it the cold pool, correct?

[senorpepr]

Yes, but the cold pocket isn't advance on the circulation. That's my point. That's how it's sustaining some convection over the circulation.

[brunota2003]

Which means that it is not latent heat being released aiding the storms (warm core) but instead the dynamics associated with something similar to a small scale cold front or sea breeze. Bleh...trying to think of a good example and it isnt working >>

[DanieleItalyRm]

Im very sorry boy but this is a warm core cyclones..
In cold core cyclones not possible the convection in the center.
To night another intensification thunderstorm activity in the center.

[senorpepr]

Actual analyses have cold pockets at 500, 700, and 850 hPa. Furthermore, you absolutely can have convection over the center of cold core systems. It's not odd at all. Nothing is remotely tropical with this system. Just a Portuguese Low.

[Ad Novoxium]

Im very sorry boy but this is a warm core cyclones..
In cold core cyclones not possible the convection in the center.
To night another intensification thunderstorm activity in the center.

Convection can be present over the core of a cold-core cyclone. And vice versa with warm core, especially if there's no real "center". For instance, 05's Arlene had almost no convection over what is defined as its center for most of its life (in this case, to quote the TCR, Arlene had "various centers rotating around a larger gyre").