ATL: TROPICAL DEPRESSION ALEX - DISCUSSION

[tolakram]

Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=25

Looks to me like shear is abating as high clouds are starting to build northwestward. Any thoughts on this observation?

[brunota2003]

AF Met, what is your current thinking on this system as far as track goes? I probably missed your post on it somewhere, so

I am still (and have been since Friday) calling for a near the border hit...50 miles either side. I concede that it is a good thing Alex is taking his own sweet time in the southern Gulf and this is why the GFS has switched to the west...not for any other reason. If Alex were moving at 10 kts...he would likely follow the GFS tracks from yesterday because he would outrun the ridge.

I did a micro analysis of the heights at 500 mb from 12z... and the path is open for him to move NNW towards the upper TX coast. THat is where the break currently is. IF he begins to move with any purpose over the next 6 hours...the forecast models will shift north. If he meanders down there...they will shift south of BRO again.

Thanks! There were a few people who were wondering what you had to say about this system.

[Tireman4]

AF Met, what is your current thinking on this system as far as track goes? I probably missed your post on it somewhere, so

I am still (and have been since Friday) calling for a near the border hit...50 miles either side. I concede that it is a good thing Alex is taking his own sweet time in the southern Gulf and this is why the GFS has switched to the west...not for any other reason. If Alex were moving at 10 kts...he would likely follow the GFS tracks from yesterday because he would outrun the ridge.

I did a micro analysis of the heights at 500 mb from 12z... and the path is open for him to move NNW towards the upper TX coast. THat is where the break currently is. IF he begins to move with any purpose over the next 6 hours...the forecast models will shift north. If he meanders down there...they will shift south of BRO again.

Thanks again AFM for a great analysis!!! Clear and to the point.

[KWT]

I did a micro analysis of the heights at 500 mb from 12z... and the path is open for him to move NNW towards the upper TX coast. THat is where the break currently is. IF he begins to move with any purpose over the next 6 hours...the forecast models will shift north. If he meanders down there...they will shift south of BRO again.

I agree, my only worry would be the weakness doesn't close as fast as the models predict, if there is one weakness overall with models is that they can be rather on the progressive side, of course doesn't mean that will happen but we've seen upper low features refuse to move out of the way many many times before, thats why I'm not going to discout anything right now...

That being said I've been on board with TX/MW landfall and I still think that your going to be right on that call...very close to Dolly IMO...

[cycloneye]

Final pass of present mission yielded lowest pressure of 989.8 mbs,a tad lower than the previous one.

[Comanche]

Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=25

Looks to me like shear is abating as high clouds are starting to build northwestward. Any thoughts on this observation?

All I see is a large area of dry air consolidating and moving into the NW quadrant, which is not going to help Alex.

here is where I am looking to see this- http://www.ssd.noaa.gov/goes/east/watl/flash-wv.html

[Air Force Met]

I did a micro analysis of the heights at 500 mb from 12z... and the path is open for him to move NNW towards the upper TX coast. THat is where the break currently is. IF he begins to move with any purpose over the next 6 hours...the forecast models will shift north. If he meanders down there...they will shift south of BRO again.

I agree, my only worry would be the weakness doesn't close as fast as the models predict, if there is one weakness overall with models is that they can be rather on the progressive side, of course doesn't mean that will happen but we've seen upper low features refuse to move out of the way many many times before, thats why I'm not going to discout anything right now...

That being said I've been on board with TX/MW landfall and I still think that your going to be right on that call...very close to Dolly IMO...

I was worried about the same thing until I analyzed the 12Z chart of the US and compared it to yesterdays. The ridge is building rapidly over the Rockies. It is, however, pretty far to the north and Alex would be able to move to the NNW for a while before it bumps into it.

[tolakram]

Loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=25

Looks to me like shear is abating as high clouds are starting to build northwestward. Any thoughts on this observation?

All I see is a large area of dry air consolidating and moving into the NW quadrant, which is not going to help Alex.

here is where I am looking to see this- http://www.ssd.noaa.gov/goes/east/watl/flash-wv.html

WV loop: http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=25

I'm not seeing a big issue with dry air.

[HURAKAN]

Alex seems to be struggling a little this afternoon

[KWT]

Ah fair enough AFM, the good news seems to be the shear slightly weakening the system perhaps has allowed the system to wobble back more to a true NW direction. It'd be better if the system either picked up a little bit more latitude then forecasted or to be a little bit further south, the region the models are homing in on would give some very high winds to some very populated regions.

[I-wall]

Looks like the LLC of Darby is getting sucked towards the LLC of Alex.

[HURAKAN]

Alex continues to be immense

[BigA]

According to this map, there is significant merit to the statement that a movement northwest will serve to move Alex into a region of less shear



Uploaded with ImageShack.us

Here is the heat content for the relevant region



Uploaded with ImageShack.us

In any case, Alex should do better as he moves northwest, and he appears to be doing so per latest Ramsdis loop.

[SunnyThoughts]

[Sanibel]

You can see there is movement of that front through Mexico:



http://www.ssd.noaa.gov/goes/west/weus/flash-wv.html




.

[HURAKAN]

I also fall victim to the time zones. I was about to ask if the NHC had forgot to issue the 1 pm intermediate advisory, LOL

[Air Force Met]

Ah fair enough AFM, the good news seems to be the shear slightly weakening the system perhaps has allowed the system to wobble back more to a true NW direction. It'd be better if the system either picked up a little bit more latitude then forecasted or to be a little bit further south, the region the models are homing in on would give some very high winds to some very populated regions.

I wrote a little note in the recon thread about the pressure change. Its likely diurnal. I wouldn't get too excited.

Here is what I said: "Diurnal changes. 10 am is usually the diurnal max for pressure...accounting for a 2-3 MB increase in pressure from 4 am - 10/11 am. 4 PM is usually the diurnal min and you can get a 2-3 mb drop during that time."

In actuality, Alex's current condition ought to make us all very concerned. The poster who got a little crucified earlier was really not that far off when he said it could be a cat 4. The same thing was said this morning by an official source. I wont say where...and when...but it was talked about. Fact is, Alex is sucking in dry air off of Mexico...its getting sheared some...it lacks a great inner core...its sitting over some of the lowest TCHP and coolest SST's in the Gulf...

And it has a 989 mb pressure which is steady/falling. It FELL 5 MB over LAND...

As a Pro-Met...that gives me a LOT of concern. I do not look at him as something ragged or pathetic...disorganized. I am kinda of worried that once he gets the tools he needs...its Katy bar the door.

[Dean4Storms]

Looks like a north movement now. As slow as it is moving I don't see how it beats the ridge behind the trough and makes it any further north before getting pushed back westward than around the border area.


Of course this be this Homies opinion only and you and your crew should get the smack from the official crew and not make any moves based on this.

[KWT]

You really think it could be a major AFM??

I've personally been 'forecasting' bout 85-95kts as a peak on the forum I'm on with perhaps a slight weakening due to the large circulation as it drags in slightly more stable air from land, similar effects to Dolly...

Still I think your right, I've been a little baffled why the models have only strengthened this to about 65-70kts, as long as that ULL does move out the way its got time to strengthen quite nicely.

[Weatherfreak000]

I am really concerned this evening for the future of Alex.

[img]http://www.nhc.noaa.gov/refresh/graphics_at1+shtml/150224.shtml?radii#contents[/img]


This has been the general motion. I'd guess i'm looking at about NNW. If I live anywhere on the WGOM (that includes Lake Charles region) I would be highly concerned.

According to the past 36 hours in forecasting for the NHC Alex is moving a whole degree slower to the west. This has many impacts on the system and not all are necessarily good as wind shear is a problem. The worst issue being the slowdown however, as we are still watching the storm meander about. It makes we wonder if Alex has some surprised in store.