ATL: ALBERTO - Post-Tropical

[brunota2003]

Here's a 1km visible image with surface, ship, and buoy observations overlaid onto the image:

[KatDaddy]

With storms now firing very close to the LLC I expect it will become our first TD or TS of 2012.

[stormhunter7]

I should note that the surface center is displaced to the east of deep convection, which suggest and you can see is the light shear. so its not perfect, but the curved banding is visible in all areas of low, and the data shows we have a very small low. I'd say the current movement is to the wsw at a very slow pace.

[cycloneye]

Tropical Cyclone Formation Alert

All the pieces are there now for NHC to decide what to do. The TAFB classification, the TCFA,the ASCAT pass etc.


SUBJ/TROPICAL CYCLONE FORMATION ALERT//
WTNT21 KNGU 191800Z
RMKS/1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE
WITHIN A 100 NM RADIUS OF 32.4N 77.7W WITHIN THE NEXT 24 HOURS.
AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF A NUMBERED TROPICAL
CYCLONE WARNING AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED
TO BE 30 TO 35 KNOTS. METSAT IMAGERY AT 191555Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 32.4N 77.7W. THE SYSTEM
DISPLAYS A WESTWARD DRIFT LESS THAN 05 KNOTS.
2. REMARKS: SATELLITE AND RADAR IMAGERY INDICATE THAT THE AREA OF
LOW PRESSURE LOCATED ABOUT 120 MILES SOUTHEAST OF MYRTLE BEACH
SOUTH CAROLINA HAS BEGUN TO ACQUIRE TROPICAL CHARACTERISTICS. MODEL
GUIDANCE DEPICTS THE AREA OF INTEREST DRIFTING WESTWARD WITH
SHOWERS AND THUNDERSTORMS PRESISTING NEAR THE CIRCULATION CENTER.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
201800Z.//
9312051912 324N 777W 30

[brunota2003]

TAFB at T2.0

AL 93 201205191745 DVTS 3210N 7780W SAB EG 1515 ///// T DT=2.5 BO CBND MET=1.5 PT=1.5 FTBO CON

AL 93 201205191745 DVTS 3220N 7770W TAFB SS 2020 ///// T DT 2.0 BO CURVED BAND

This is a good example of how the Dvorak T numbers can underestimate the intensity of a cyclone:

19/1745 UTC 32.1N 77.8W T1.5/1.5 93L -- Atlantic

T1.5 means it was run as tropical, and the satellite estimates for strength are at 25 knots...whereas real world observations have shown winds of at least 29.1 knots (8-minute observing period), or if the ship reports are accurate, winds of at least 30 to 35 knots are present.

[TropicalAnalystwx13]

If we're to get Alberto at 5 pm, watch for a Renumber over the next hour to hour and a half.

[brunota2003]

Just because there is a renumber does not mean there will be advisories. I've seen them do renumbers, just to decide in the end to cancel it. So nothing is official until an actual advisory is issued!

[RL3AO]

Just because there is a renumber does not mean there will be advisories. I've seen them do renumbers, just to decide in the end to cancel it. So nothing is official until an actual advisory is issued!

Once or twice. Realistically a renumber means advisories.

[cycloneye]

Just because there is a renumber does not mean there will be advisories. I've seen them do renumbers, just to decide in the end to cancel it. So nothing is official until an actual advisory is issued!

Bingo my friend to that!!

[SouthDadeFish]

Looks like 93L is shooting out a ton of outflow boundaries to the S over the past couple of hours... I wonder if the convection will collapse soon.

[TropicalAnalystwx13]

I don't see any outflow boundaries...I do see inflow bands though.

[stormhunter7]

I dont really see outflow... maybe the blow off from the small CDO, that's sheared and fighting dry air on the east side.

http://www.ssd.noaa.gov/PS/TROP/floater ... -long.html

[SouthDadeFish]

I don't know how to post animated loops here, but if anyone could post the close-up visible loop from WeatherTap you can see a lot of low-level clouds moving away from the center on the south side.

[cycloneye]

invest_RENUMBER_al932012_al012012.ren


http://ftp.nhc.noaa.gov/atcf/tcweb/inve ... 012012.ren

[TropicalAnalystwx13]

Cool!

[RL3AO]

Should be an interesting track forecast.

[bg1]

Could this be the first storm of the season?

[TexasF6]

Nice!

[stormhunter7]

did they just renumber 93L?

EGIN
NHC_ATCF
invest_RENUMBER_al932012_al012012.ren
FSTDA
R
U
040
010
0000
201205191920
NONE
NOTIFY=ATRP
END
INVEST, AL, L, , , , , 01, 2012, DB, O, 2012051912, 9999999999, , , , , , WARNING, 1, AL012012
AL, 01, 2012051812, , BEST, 0, 334N, 764W, 25, 1011, LO, 0, , 0, 0, 0, 0,
AL, 01, 2012051818, , BEST, 0, 333N, 766W, 25, 1011, LO, 0, , 0, 0, 0, 0,
AL, 01, 2012051900, , BEST, 0, 331N, 768W, 25, 1010, LO, 0, , 0, 0, 0, 0,
AL, 01, 2012051906, , BEST, 0, 329N, 771W, 30, 1009, LO, 0, , 0, 0, 0, 0,
AL, 01, 2012051912, , BEST, 0, 325N, 773W, 35, 1009, LO, 34, NEQ, 30, 0, 30, 30, 1012, 50, 40, 40, 0, L, 0, , 0, 0, INVEST, S,
AL, 01, 2012051918, , BEST, 0, 323N, 776W, 40, 1007, LO, 34, NEQ, 40, 0, 30, 40, 1012, 60, 30, 50, 0, L, 0, , 0, 0, INVEST, M,

[cycloneye]

New Best Track with Tropical Storm Alberto

AL, 01, 2012051918, , BEST, 0, 323N, 776W, 40, 1007, TS


http://ftp.nhc.noaa.gov/atcf/tcweb/inve ... 012.invest