ATL GUSTAV: Tropical Depression - Discussion

[wxman57]

Huh? Im not seeing any blocking high in the gulf when the gfdl indicates 94L to be getting int the gulf..all I see is a building high to the west blocking any west movement..all assuming if the gfs and gfdl are correct..

You're also not looking at Friday's forecast. You're looking at Sat/Sun. The high does appear to break down over the weekend. But if 94L is already in the SW Gulf by Saturday then the ridge is still to its north. Lots of assumptions, I grant you.

[Ivanhater]

Huh? Im not seeing any blocking high in the gulf when the gfdl indicates 94L to be getting int the gulf..all I see is a building high to the west blocking any west movement..all assuming if the gfs and gfdl are correct..

You're also not looking at Friday's forecast. You're looking at Sat/Sun. The high does appear to break down over the weekend. But if 94L is already in the SW Gulf by Saturday then the ridge is still to its north. Lots of assumptions, I grant you.

Oh..well this thing better not slow down, at least for the U.S sake!

[wxman57]

isn't there a little weakness in those GFS forecast fields? I would think that would mean WNW, possibly followed by due west. regardless... still looks like a Mexican landfall if this misses the weakness predicted at 75W

What was that storm a year or two ago where the GFS predicted a giant ridge over Florida and the NHC commented that no way could this thing turn to Florida because of the ridge? Well, the GFS was wrong and there was no ridge. This is what makes hurricane forecasting a challenge.

Time for bed. I'm on the forecast desk early shift tomorrow.

[Fego]

Almost there?

24/2345 UTC 13.7N 67.5W T1.5/1.5 94L -- Atlantic Ocean

[ROCK]

just curious on why the NHC has not upgraded to red yet? seems organizing pretty quickly with a lot of cold tops.... LLC or not...

[Aric Dunn]

TCFA issued

WTNT01 KNGU 250001
SUBJ/TROPICAL CYCLONE FORMATION ALERT 250000Z AUG 08//
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
100 NM EITHER SIDE OF A LINE FROM 12.9N 66.5W TO 15.5N 72.4W
WITHIN THE NEXT 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 20 TO 25 KNOTS. METSAT
IMAGERY AT 250000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 13.5N 67.7W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10
TO 15 KNOTS.
2. REMARKS: A BROAD AREA OF LOW PRESSURE IS BEGINNING TO
DEVELOP ALONG AN EASTERLY WAVE IN THE EASTERN CARIBBEAN
SEA, ROUGHLY 300NM TO THE SOUTH-SOUTHEAST OF PUERTO RICO, MOVING
TO THE WEST-NORTHWEST. ESTIMATED CENTRAL PRESSURE IS 1008MB WITH
SURFACE WINDS OF 20 TO 25 KNOTS ALONG THE NORTHERN PERIPHERY
OF THE SYSTEM. AREAS OF CONVECTION ARE GRADUALLY BECOMING BETTER
ORGANIZED AND ROTATION IS EVIDENT IN VISIBLE SATELLITE IMAGERY.
LOW VERTICAL WIND SHEAR CONDITIONS AND WARM SEA SURFACE TEMPERATURES
(82F) EXIST DOWNSTREAM INTO THE CENTRAL CARIBBEAN SEA ENHANCING
THE POSSIBILITY FOR TROPICAL CYCLONE DEVELOPMENT.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED
BY 260000Z.//

[Chigger_Lopez]

isn't there a little weakness in those GFS forecast fields? I would think that would mean WNW, possibly followed by due west. regardless... still looks like a Mexican landfall if this misses the weakness predicted at 75W

What was that storm a year or two ago where the GFS predicted a giant ridge over Florida and the NHC commented that no way could this thing turn to Florida because of the ridge? Well, the GFS was wrong and there was no ridge. This is what makes hurricane forecasting a challenge.

Time for bed. I'm on the forecast desk early shift tomorrow.

It was Ernesto

[rockyman]

[Aric Dunn]

[cpdaman]

as of 245 utc deep convection (black) stretching from 14/68 to 15/ 67

[Dean4Storms]

I thought the "zone of death" sentence would get Ortt going, that got discussed thoroughly years ago, LOL!

Not a good sign to see convection refiring tonight behind the wave axis and rotating.

[ROCK]

geez, very cold tops showing up now....this thing is ready to blast off...

http://www.ssd.noaa.gov/goes/flt/t2/loop-avn.html

[ROCK]

might go to TS status by the time RECON gets in there and skip TD....if it keeps this up...

[GeneratorPower]

Very nice looking on IR indeed, ROCK.

[SouthFLTropics]

might go to TS status by the time RECON gets in there and skip TD....if it keeps this up...

Wouldn't be the first time it has happened this year...They way it's looking I wouldn't be suprised if it went straight to TS status. It looks to be winding up pretty good tonight.

SFT

[ROCK]

might go to TS status by the time RECON gets in there and skip TD....if it keeps this up...

Wouldn't be the first time it has happened this year...They way it's looking I wouldn't be suprised if it went straight to TS status. It looks to be winding up pretty good tonight.

SFT

yes it does.....put good odds on this being a TD by the time we wake up and a TS by noon tomorrow (or sooner)...

[GeneratorPower]

I think it will have to do with convection overnight maintaining itself. Might have a TD at the 5am package if they want to get a jump on things. More than likely they will wait until 11am to start advisories, and follow it up with recon that afternoon.

[cpdaman]

i agree lets see if this can maintain some solid convection near a center. likely IMO

[Praxus]

Looks great on IR, I think its time for liftoff

[BigA]

This thing looks wicked intense for a pre-TD wave/invest, and I wouldn't be surprised in the least if we have Gustav by tomorrow, but I kept thinking the same thing with Pre-Fay and Pre-Dolly for a while, but the LLC took a long time to develop with both of those systems. Per usual, recon will tell the tale tomorrow.