ATL HANNA: Extratropical - Discussion

[NEXRAD]

LOL....I am posting too much right now..Sorry!

Look at the low level convergence...WOW...

http://cimss.ssec.wisc.edu/tropic2/real ... oom=&time=

Obviously we know how well the upper divergence is....

http://cimss.ssec.wisc.edu/tropic2/real ... oom=&time=

I don't know If I have ever seen those that high before.

Much agreed; Hanna definitely has not been lacking in terms of impressive convection, and the excellent convergence/divergence are definitely responsible.

- Jay

[Raebie]

She looks pretty healthy for a gal that's been getting the crap kicked out of her for the last 12+ hours.

Question, around this weekend, what's the outlook for her & Gus meeting up over the Southeast?

[KWT]

Yeah I was going to say Deltadog the convergence and upper divergence is pretty crazy for Hanna, any convective blow up will be very strong and in some ways thats why I suspect Hanna is still got pressure as low as it has thanks to the strong convection. Once the shear turns off to a good degree then I think with 12hrs of re-organisation we could see some pretty rapid development occur.

[NEXRAD]

She looks pretty healthy for a gal that's been getting the crap kicked out of her for the last 12+ hours.

Question, around this weekend, what's the outlook for her & Gus meeting up over the Southeast?

Depends what part of Gustav you look at. Hanna seems poised to work in-tandem with Gustav's mid-level remnants to weaken the Atlantic ridge over the Ern US towards the weekend if the current model guidance and/or TPC track proves true.

- Jay

[BigA]

Once the shear turns off to a good degree then I think with 12hrs of re-organisation we could see some pretty rapid development occur.

Is this more of an if, or a when? The NHC discussions seem to say that the globals show decreasing shear, and I tend to trust them, but is there anything particularly to look for on water vapor or visible that shows decreasing shear, rather than merely the effects of less shear? (deep convection around the center, better organization)

[HurricaneQueen]

While we are debating the "what ifs", may I please make a personal appeal for posters to go to the Control Panel and input their location. It need not be exact but SE FL , NW FL, GA coast, etc would be most helpful when reading personal predictions.

Thanks, as this has been a pet peeve for a long time. It is most disconcerting when someone says it is headed "here" and we have no idea where here is.

Keep up the great work everyone and most especially the Pro Mets and other most knowledgeable posters. Looks as if we are in for the long haul with Hanna, Ike and Josephine lined up. Will be watching all three very carefully as always.

Lynn

[Cookiely]

All I can say are the visible shots of Hanna were worth waiting for. She's incredible. What is causing that burst of convection towering in the center.

[terrapintransit]

Watch how Hanna just explodes in size over the past 6 hours....

http://weather.myfoxtampabay.com/maps/W ... bbean.html

[jhpigott]

she is one big mother

[OuterBanker]

If Hanna waits long enough won't Ike have some influence as to where and when she moves (while throwing a monkey wrench).

[KWT]

BigA, well with shear its always more of a case of if, not when but I suspect the shear will ease down gradually, maybe not for another 12-24hrs now.

The biggest fear is that Hanna makes landfall in a similar place to where Fay stalled, given the flooding issues even a fairly quick moving system like Hanna is forecasted to be once it does head NW, there could be some bad flooding.

[Aristotle]

Watch how Hanna just explodes in size over the past 6 hours....

http://weather.myfoxtampabay.com/maps/W ... bbean.html

Again I'm a huge nothing with regard to knowledge and the weather. But...(with that said ) is it possible that as the remnants of gus move to the south side of Hanna that it can act as a turbo charging inflow jet in addition to the inflow that Hanna already has? is that a possible explanation of the blow up of the convection?

In addition as that remnant outflow of Gus moves south it seems that it stops shearing and starts feeding? Am I completely loopy here? At least it seems that Hanna is taking on a less sheared look.

Your thoughts?

[NEXRAD]

Watch how Hanna just explodes in size over the past 6 hours....

http://weather.myfoxtampabay.com/maps/W ... bbean.html

Again I'm a huge nothing with regard to knowledge and the weather. But...(with that said ) is it possible that as the remnants of gus move to the south side of Hanna that it can act as a turbo charging inflow jet in addition to the inflow that Hanna already has? is that a possible explanation of the blow up of the convection?

In addition as that remnant outflow of Gus moves south it seems that it stops shearing and starts feeding? Am I completely loopy here? At least it seems that Hanna is taking on a less sheared look.

Your thoughts?

Gustav's remnants will cycle around ridging located over the Eastern US. Therein, the remnant will not move into Hanna's south side. By the time Hanna interacts with Gustav's remnant, if that happens at all, it will be over the Middle Atlantic or Northeast US, and Hanna will no longer be a tropical cyclone.

Gustav's outflow has been affecting Hanna, but more so because of the Gulf upper level ridge placement.

- Jay

[Aristotle]

Watch how Hanna just explodes in size over the past 6 hours....

http://weather.myfoxtampabay.com/maps/W ... bbean.html

Again I'm a huge nothing with regard to knowledge and the weather. But...(with that said ) is it possible that as the remnants of gus move to the south side of Hanna that it can act as a turbo charging inflow jet in addition to the inflow that Hanna already has? is that a possible explanation of the blow up of the convection?

In addition as that remnant outflow of Gus moves south it seems that it stops shearing and starts feeding? Am I completely loopy here? At least it seems that Hanna is taking on a less sheared look.

Your thoughts?

Gustav's remnants will cycle around ridging located over the Eastern US. Therein, the remnant will not move into Hanna's south side. By the time Hanna interacts with Gustav's remnant, if that happens at all, it will be over the Middle Atlantic or Northeast US, and Hanna will no longer be a tropical cyclone.

Gustav's outflow has been affecting Hanna, but more so because of the Gulf upper level ridge placement.

- Jay

Agreed Jay but as I look at the wide view of the Atlantic it seems as if Gus' outflow seems to be going directly into Hanna. Regardless of reasons. Visibly you can see that happening. So in my mind it seems as if gus is feeding Hanna. Am I missing the point?

[HURAKAN]

[NEXRAD]

Aristotle,

Gustav's outflow is indeed circulating over Hanna, but the reason for that is an upper level ridge is present over the Eastern Gulf of Mexico. Therefore, Gustav is indirectly affecting Hanna, but a greater influence on Hanna is coming from the upper level flow that goes between the Gulf ridge and the trough off Nova Scotia. As the upper level air squeezes between these two features (offshore Georgia, roughly) the wind gets stronger and causes shear. As these winds approach Hanna, though, they spread out over a larger area, creating divergence. This divergence aloft helps to evacuate air from the convection around Hanna's center. This, likewise, helps the convection to keep going.

A good example of why the upper level winds help the system is noticed when comparing typical summer thunderstorms over the Southeast to those that occur with strong fronts. The basic explanation is as follows. The daytime thunderstorms occur in an environment with limited upper level wind. This causes the convection to build up and then collapse on itself, so the storms don't last that long. With strong frontal convection, the strong flow aloft helps the thunderstorm updrafts and helps keep the convection going.

- Jay

[windycity]

Deltadog03, Thanks for your posts, and keep posting!!! What are your feelings about hanna's track? for the past week i kept waiting a change from the euro, so maybe they were on to something!! What do you think??

[Evil Jeremy]

Awaiting the new advisory. Ike and Josephine have already had their advisories issued, but the NHC seems to be waiting for some reason/

[Weatherfreak14]

Im live i Beaufort, Sc and it seems the bullseye has been me for the past 3days and im leaving tommmrow for evacuation.... I hate to say it but i truely think that the current forcast of a big impact of my town will be holding true of a landfalling CAT 2 hurricane...around Savannah, Ga or Hilton Head, SC.

[NEXRAD]

Awaiting the new advisory. Ike and Josephine have already had their advisories issued, but the NHC seems to be waiting for some reason/

The TPC might have coordination calls with various Florida NWSFO's to discuss watch placements/timings... just a guess.

- Jay