ATL HANNA: Extratropical - Discussion

[KWT]

Indeed Nimbus still needs to be watched if it can get a decent synoptic set-up but right now it looks pretty hidious...

The models have totally screwed this up this time round!

[deltadog03]

Looks like our tight little LLC might be opening up some...VDM came in saying broad low pressure...so.....She might be on last leg?? With that said though, she has and is a fighter so she could easily come back.

[loxahatchee13]

If this storm survives, I recall a couple days ago or mabey yesterday there was some discussion regarding the ridge building in and the longer Hannah stayed south how it increased the risk of the storm possibly veering more to the west. Is this still plausible or do the models have a pretty good handle on this track now and this strom should be more of a Georiga and Carolina storm?

[Tertius]

If this storm survives, I recall a couple days ago or mabey yesterday there was some discussion regarding the ridge building in and the longer Hannah stayed south how it increased the risk of the storm possibly veering more to the west. Is this still plausible or do the models have a pretty good handle on this track now and this strom should be more of a Georiga and Carolina storm?

I have been trying to determine the likelihood of precisely that scenario, since Hanna continues to ignore all of the forecasts saying it should be whipping north by now. The upside to that of course is that given it's current position it is just as likely to tear itself apart on the DR before it ever gets moving. In the end I don't have a clue.

[HURAKAN]

[KWT]

It wouldn't be all that surprising if that was happening Deltadog, it does look very poorly right now though there is some convection still flaring up close to the center.

[carolina_73]

She finally took that North turn this morning. It's a start. I think I can ..I think I can...

[gatorcane]

There's not doubt in my mind looking at Hanna this morning that she's on the verge of rebounding pretty quickly and I agree with the NHC forecast of a strengthening from here on out all the way to landfall....

For one thing the shear has relaxed substantially today from yesterday.

[KWT]

I don't think its going to rebound very quickly for a little while yet gatorcane given the presentation is total rubbish right now, however there is still very deep convection firing, that should give a good idea that once it getws some better convection over its center it should strengthen again.

[Thunder44]

I haven't see any recon reports this morning that support this storm being 50kts. So don't be suprised if at 8am NHC decreases the winds to 40-45kts. It's a large system. So I do think it will survive and l make a comeback later today or tonight. If the track is further east, it would have more time over water, before landfall to organize and strengthen.

[KWT]

Yeah the NHC may well lower Hanna down to 40-45kts given the highest flight level winds were 48kts I believe from what I've seen.

Its probably got between 72-96hrs to get its game on so to speak, its certainly enough time for this to do some nifty strentgthening I'd have thought if it does ever get a more condusive set-up, at least the shear seems to be slowly easing up now.

[BensonTCwatcher]

The vector of the shear has changed overnight and now it looks to be helping with outflow aloft. The shear is still there but now it letting off somewhat and as the anticyclonew that was over Gustav is gone. The big player for development is still that ULL to the N. There is an upper level trough to the NW of the system which looks to continue to move W. The ULL hasn't really started to move out yet, but you can see the ridge building in from the W and pushing on the E side of the ULL and also look over Wisconsin, where you can see the H over the midwest movinng east as forecast by the GFS. Soon the ULL with have to move out and we'll a gradual increase in Hanna's movement today.

Strength is the big variable to me right now. The NHC intensity forecast seems right on BUT it will be very hard to determine intensity at landfall. I think this could be a weak TS or a Cat 2 at this point. If the setup is right and it tracks a little more East (longer over water) then we could have a stronger storm at landfall. To make Cat 2 though, it will need to capitalize on the warmer water in the Bahamas. Once past the Gulf stream cooler waters are near the shore. Thank goodness the stall is ending, Hanna has been an ugly lady to look at lately.

http://www.ssd.noaa.gov/goes/east/nwatl/loop-wv.html

[gatorcane]

Based on the 8Am advisory that just came out, Hanna is moving East at 5mph again.

[KWT]

Yep Benson the big uncertainty is how well the system can recover in the time its got. The set-up does look pretty decent for re-strengthen but to what extent I'm not sure, given the LLC was near opening up according to recon it may not recover su[per fast at first and only after its re-toghtened that LLC will it probably have a shot of doing anything a little more rapidly...however SST's are high and there is still clearly something there thats allowing explosive convection.

[Myersgirl]

It is hard to totally buy into the models when Hanna continues to move in the opposite direction day after day

[Bane]

well, the models weren't predicting the turn until today anyways.

[BensonTCwatcher]

Divergence http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8dvg.html

and Convergence http://cimss.ssec.wisc.edu/tropic/real-time/atlantic/winds/wg8conv.html

If the upper level winds can wrap a bit more we'll see an anticyclone form over Hanna and then lookout, but it just hasn't happened yet

[KWT]

Yep convergence is still very impressive over the center of the system and is going a decent way to explaining the very deep convection that is still developig near the center.

Its just a case of wait and see.

[jlauderdal]

looks more like a tropical system today than yesterday when it was flat, lets see what happens, im on ike alert now

[hial2]

well, the models weren't predicting the turn until today anyways.

The NHC predicted the turn north-west would commence late afternoon/early night yesterday..