ATL: TROPICAL DEPRESSION ALEX - DISCUSSION

[wxman57]

Surface obs across the disturbance do not indicate any LLC. Just ESE winds east of the wave axis and ENE winds west of the axis. I don't see any significant organization occurring yet. Probably not until late tomorrow or Friday.

[KWT]

I don't think its closed yet Wxman57 but there is some turning I think quite evident if you look at the super high resolution images that have been posted up, doesn't look very widespread nor strong yet though...could you do one of those maps if you have time with those obs btw?

ps, I don't think its at the surface just yet either, will probably need more convection first...also if it leaves it till late tomorrow/Friday to start organising, its going to need some help from the Yucatan on Friday/Sat to get going I think.

[BigA]

Surface obs across the disturbance do not indicate any LLC. Just ESE winds east of the wave axis and ENE winds west of the axis. I don't see any significant organization occurring yet. Probably not until late tomorrow or Friday.

What level do you think the spinning is occuring at right now? Because in the last few visible frames there were some low clouds rotating about. Were they at the 5000-10000 foot level?

[Dean4Storms]

This is the most convection near the apparent low since it was in the eastern Carib. If it closes off and develops tomorrow the GFS run which never closes off the low is pretty much in the dark.

[thetruesms]

Surface obs across the disturbance do not indicate any LLC. Just ESE winds east of the wave axis and ENE winds west of the axis. I don't see any significant organization occurring yet. Probably not until late tomorrow or Friday.

This is why I'm not convinced. Sure, it kinda looks like there's something there, but there's absolutely nothing else out there that supports that interpretation yet. The descending pass for the 2030Z ASCAT shows one northerly barb on the very edge in front of the wave before it drops to nothing in its gap. Just one - sorry, I'm not buying that.

[jasons2k]

Even though the satellite presentation is chaotic and totally disorganized, I also see some low level rotation west southwest of Jamaica. I am really "impressed" though with the buoy observations Irak and I-wall have posted... I remember reading one of the criteria that NHC specialists look for when evaluating potential development of a disturbance is surface pressure falls of 2-3 mb within a 24 hour period. Obviously there will be diurnal variability of rising and falling pressures so simply "falling" or "rising" is not something that important. However, when you compare the surface pressures to 24 hours previous and we are now seeing near 2 mb pressure falls during the past 24 hours over the western Caribbean Sea I think that is significant. I am thinking the surface low may actually be trying to develop late this afternoon even though satellite presentation is unimpressive, I agree with Sanibel that pressure trumps satellite imagery. Lowest pressure so far is 1009 mb which is at least 2 mb lower than I have previously observed. The ATCF Best track has always had this wave at 1010 mb but I have not seen any surface obs that verified that until today, and now it shows slightly lower than 1010. I think the long awaited development "trend" maybe begining. That being said, I still would be surprised to see tropical cyclone formation until Friday when the energy from the wave over the eastern Caribbean currently along 67W can be absorbed into this system, in my humble opinion.

One thing to remember with buoy observations is that buoys are stationary and the system is moving. A 24-hour relative pressure drop at a buoy doesn't mean the system is getting stronger, it just means it's getting closer.

[jasons2k]

Last visibles show a bunch out outflow boundaries get spit out, esp. by the circulation SW of Jamaica. There is another circulation even further South of that. Still a ways to go IMO.

[cycloneye]

Although the winds are light,they are from the north.

North wind in Roatan,Honduras

[brunota2003]

I don't get it...these waves have had near prime conditions (according to current standards) to develop, and then even intensify. Little dry air, hot SSTs, low shear, low pressures...heck, some even already had a low pressure on them! Yet they keep failing...why?

What criteria have we overlooked in the past that is clearly not there currently?

[wxman57]

I don't get it...these waves have had near prime conditions (according to current standards) to develop, and then even intensify. Little dry air, hot SSTs, low shear, low pressures...heck, some even already had a low pressure on them! Yet they keep failing...why?

What criteria have we overlooked in the past that is clearly not there currently?

We weren't expecting it to come together until Friday. Today is Wednesday. It's consolidating very slowly. Come back Friday.

[cycloneye]

Is the first time that 93L has the pressure down to 1009 mbs at Best Track.

AL, 93, 2010062400, , BEST, 0, 170N, 795W, 25, 1009 WV

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/ ... 010.invest

[bvigal]

(Really off topic, but do you know the sympotoms of A Concussion? I just knocked the living daylight's out of myself when i was playing dodgeball. OK. I walked into a tree.)

sent you a PM!

[WeatherLovingDoc]

I don't get it...these waves have had near prime conditions (according to current standards) to develop, and then even intensify. Little dry air, hot SSTs, low shear, low pressures...heck, some even already had a low pressure on them! Yet they keep failing...why?

What criteria have we overlooked in the past that is clearly not there currently?

A ha! A philosophic weather lover watcher! Got to love them.

[KWT]

I don't get it...these waves have had near prime conditions (according to current standards) to develop, and then even intensify. Little dry air, hot SSTs, low shear, low pressures...heck, some even already had a low pressure on them! Yet they keep failing...why?

What criteria have we overlooked in the past that is clearly not there currently?

Shear isn't really that low at the moment though, its not huge shear but I suppose in a system that has had trouble with convergence that shear can be the difference between it forming or not IMO at least in the short term.

[Ivanhater]

I think we should all take wxmans advice and stop torturing ourselves and come back Friday

[BigA]

It's not like this thing is out of time. Most of the models don't show it getting to the Yucatan for 3 days or so at least, and in any case, June climatology strongly favors the area farther west. I think Friday's a good bet for the best chance of development, though we should have some trends visible tomorrow.

[txagwxman]

Surface obs across the disturbance do not indicate any LLC. Just ESE winds east of the wave axis and ENE winds west of the axis. I don't see any significant organization occurring yet. Probably not until late tomorrow or Friday.

Agree...just a low-level swirl at the moment.

[txagwxman]

I tested out my generator just in case.

[lonelymike]

I think we should all take wxmans advice and stop torturing ourselves and come back Friday

Now you know you're gonna be up at 2am for the next Euro run. Who you kiddin?

[Ivanhater]

I think we should all take wxmans advice and stop torturing ourselves and come back Friday

Now you know you're gonna be up at 2am for the next Euro run. Who you kiddin?

Lol, you know me too well