ATL: HERMINE - Post-Tropical - Discussion

[ScottNAtlanta]

Long range radar loop out of MIA

http://radar.weather.gov/radar_lite.php ... Z&loop=yes

[NDG]

This convection is still to the SE of the Wave Axis and highest Vorticity, we need convection further to the NW within the top area of that wave. Still a good deal of organization needed here.

Is not a wave axis, even the NHC's TWOs state that it is a low pressure center.

I believe it's an elongated trough with an axis or embedded area of lowest pressure. If it was a closed center at the surface it would meet the TD criteria. So maybe at mid levels one can track a center, but at surface it would still be an axis.

Before it can be a TD it has to have a well defined LLC which is a criteria, which I still cannot see. But one thing for sure is that it has a closed circulation is not an open trough.

[Dean4Storms]

The 200mb Vort Streamer is now out of the way. There is good 850 and 700mb Vorticity right over the current convection the only fly in the ointment currently is the 500 Vort is still well east of the lower level Vorticity. If this convection can continue all day and and develop the area of lowest pressure at the surface beneath it we could have development tonight or tomorrow, but it isn't stacked right now so a lot of organization still remains!

[gulf701]

Thank you tolakram for the Eric Blake comment. It supports the data that I was looking as to the position of the low. It appears to me that the convection is drifting towards the circulation.





The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[HurricaneEric]

Before anyone gets complacent or thinks this is done...in 2005 there was tropical depression 10 that died off obituaries written only later to become tropical depression 12 as it got closer to FL...and we all know how that played out...it aint over till its over

THIS. Katrina was in the same general vicinity of 99L, albeit more north and east when it was classified a TD. In a matter of 24 hours, Cat 1 hurricane making landfall in SFL.

[tarheelprogrammer]

Storms catching up to the center and the northwest side of the LLC is starting to get thicker looking clouds.

Edit: When is shear supposed to hit this system again?

[ScottNAtlanta]

I tried to say that without using the "K" word...

[abajan]

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the National Hurricane Center and National Weather Service

OK, now that i have that out of the way...let me get to my observations and thoughts ...

Actually, that disclaimer is no longer required, but many of us seem to be unaware of this. Nevertheless, thanks for sharing your thoughts on the future of 99L. I'm inclined to believe it will develop too.

[ronjon]

The 200mb Vort Streamer is now out of the way. There is good 850 and 700mb Vorticity right over the current convection the only fly in the ointment currently is the 500 Vort is still well east of the lower level Vorticity. If this convection can continue all day and and develop the area of lowest pressure at the surface beneath it we could have development tonight or tomorrow, but it isn't stacked right now so a lot of organization still remains!

Good analysis Dean. That's why I think it will slowly organize. Important player today is heavy convection which can induce low pressure, lower shear, and slow forward speed.

[Recurve]

Everyone seems to be seeing more organization, although I don't have any idea about a focus. NHC is still at only 20% and talking about strong shear it seems. I have to go with the experts that it's unlikely to be a TD even 48 hours out...except maybe the tune with change when surface obs do show westerly winds south where a center might form. I dunno. It seems to be a classic developing TD but it's obviously got a way to go...
I am concerned that we could get classic rapid intensification in the gulf and a bad trajectory toward SW Florida... but maybe it stays a weak wave until it's mid Gulf, and then LA and MS are more in the crosshairs.

[NDG]

Before anyone gets complacent or thinks this is done...in 2005 there was tropical depression 10 that died off obituaries written only later to become tropical depression 12 as it got closer to FL...and we all know how that played out...it aint over till its over

THIS. Katrina was in the same general vicinity of 99L, albeit more north and east when it was classified a TD. In a matter of 24 hours, Cat 1 hurricane making landfall in SFL.

Conditions are nothing close to as ripe as they were in 2005 in this area.

[SapphireSea]

Before anyone gets complacent or thinks this is done...in 2005 there was tropical depression 10 that died off obituaries written only later to become tropical depression 12 as it got closer to FL...and we all know how that played out...it aint over till its over

THIS. Katrina was in the same general vicinity of 99L, albeit more north and east when it was classified a TD. In a matter of 24 hours, Cat 1 hurricane making landfall in SFL.

Katrina had a vastly different air setup. To be sure it should most definitely be monitored for the gulf coast. But this is way more elongated than Katrina was, and Katrina was under an upper high which 99L does not have. It remains to be seen if 99L will get upper air support and instability to really close off and take off later in SE gulf.

[ScottNAtlanta]

Before anyone gets complacent or thinks this is done...in 2005 there was tropical depression 10 that died off obituaries written only later to become tropical depression 12 as it got closer to FL...and we all know how that played out...it aint over till its over

THIS. Katrina was in the same general vicinity of 99L, albeit more north and east when it was classified a TD. In a matter of 24 hours, Cat 1 hurricane making landfall in SFL.

Conditions are nothing close to as ripe as they were in 2005 in this area.

I was speaking more conceptually that literally...thats why I didnt use the name. Just is evidence that a system can almost dissipate and regenerate quickly in this area

[SapphireSea]

THIS. Katrina was in the same general vicinity of 99L, albeit more north and east when it was classified a TD. In a matter of 24 hours, Cat 1 hurricane making landfall in SFL.

Conditions are nothing close to as ripe as they were in 2005 in this area.

I was speaking more conceptually that literally...thats why I didnt use the name. Just is evidence that a system can almost dissipate and regenerate quickly in this area

Understandable, just notable to say that given correct conditions this is possible anywhere in the basin. Upper air model and mid level and low level models need to be manually analyzed to forecast out 24 48 to see if the environment looks favorable. From the beggining even those models blowing this up to cat 5 distinctly showed poor mid level and upper level environments for development. Ignore the closed lows on models focus more on the setup in each layer.

[GCANE]

Main convection at 37GHz on WINDSAT looked really good about 3 hrs ago.
Still holding up well on IR.

Looks like the 30N 70W ULL will get washed out in a couple hours.

[robbielyn]

Point well taken. You can't make cookies if u leave a couple ingredients out. or it will be a sloppy mess on the cookie sheet. You can't leave out key ingredients in a wave expecting it to come together well if a couple of things are missing either. It too will be a sloppy mess. You can have a full tank of fuel in a car to give it power but if a couple of cylinders aren't firing nothin's going to happen. the TW can have all the hot water aka fuel for its engine but if its missing consolidation aka running on all cylinders it won't develop. As we know however, these systems can generate their own conditions to facilitate intensification. So it still has a chance for sure compared to yesterday. its in a more favorable environment.

[toad strangler]

NHC plainly states in the 8AM that up level winds are NOT conducive for development for "a day or so"
It has been so long since we have had a good red meat cyclone to track that each and every hot tower that spikes near a possible COC leads to fools gold hope.

[Agua]

Everyone seems to be seeing more organization, although I don't have any idea about a focus. NHC is still at only 20% and talking about strong shear it seems. I have to go with the experts that it's unlikely to be a TD even 48 hours out...except maybe the tune with change when surface obs do show westerly winds south where a center might form. I dunno. It seems to be a classic developing TD but it's obviously got a way to go...
I am concerned that we could get classic rapid intensification in the gulf and a bad trajectory toward SW Florida... but maybe it stays a weak wave until it's mid Gulf, and then LA and MS are more in the crosshairs.

Basically the excitement was about watching an LLC develop in pretty much real time out of a mess of swirling clouds. It looks like garbage and all but the south and east / northeast sides are bare, but there wasn't an identifiable circulation 2 hours ago.

[GCANE]

Seeing a 1C warm core now at 10km with a 2C inversion at about 1km.
Watching if the inversion gets knocked out.

[BobHarlem]

Starting to see a hint of something on the long range Miami radar, just not enough detail yet.

radar: http://radar.weather.gov/ridge/radar.ph ... 1&loop=yes
longer loop of same radar: http://flhurricane.com/imageanimator.php?217