ATL: HANNA - Remnants - Discussion

[tolakram]

SLIDER 1min MESO

https://rammb-slider.cira.colostate.edu/?sat=goes-16&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=mesoscale_01&p%5B0%5D=band_02&x=784.9517059326172&y=777.4090881347656

I don't see any significant shear, what am I missing?

[1900hurricane]

Pretty classic curved band on satellite imagery. Less than half a wrap of a white band is good for a DT of 3.0 I'd say, which looks pretty clear cut to me.

[tarheelprogrammer]

SLIDER 1min MESO

https://rammb-slider.cira.colostate.edu/?sat=goes-16&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=mesoscale_01&p%5B0%5D=band_02&x=784.9517059326172&y=777.4090881347656

I don't see any significant shear, what am I missing?

Just an opinion here, but I believe the dry air from the US mainland is collapsing the thunderstorms on the NW side of the storm and thus it cannot wrap convection all the way around currently. This is just my two cents and it could likely change if I am correct. You can see the clouds in Texas have that dry look to them. Just an observation.

[HurricaneAndre2008]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 24 JUL 2020 Time : 192023 UTC
Lat : 27:22:00 N Lon : 93:51:52 W


CI# /Pressure/ Vmax
3.4 / 989.1mb/ 53.0kt

We need recon now.

[aspen]

Are there any more flights scheduled for today? Or will we have to wait until tomorrow?

[wxman57]

HWRF showing possible hurricane force winds for southern coastal Corpus Christi area tomorrow afternoon into the evening. Storm doesn't look as bad as it could have been, probably due to the slightly drier environment. Forecast looks pretty straight forward unless there is an unexpected stall. NHC might issue hurricane watches later if necessary but it looks like most of the wind damage will be short lived at landfall. The models show Hanna drying out fairly quickly once she gets inland.

HWRF does OK sometimes, but most times it is too high with intensity. For example, it has Gonzalo up to 78 kts in the next 12 hours. Maybe closer to 7-8 kts than 78 kts.

[xironman]

SLIDER 1min MESO

https://rammb-slider.cira.colostate.edu/?sat=goes-16&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=mesoscale_01&p%5B0%5D=band_02&x=784.9517059326172&y=777.4090881347656

I don't see any significant shear, what am I missing?

It is/was mid-level shear. So you have a situation where the cirrus seems fine and the lower clouds as well, but the middle is missing. I remember many years ago when Derick Ortt had a great post on it here.

[NDG]

Will somebody tell the young guy at TWC that typically tropical storms don't have that much lightning if at all in its core?
Recently I watched a movie in which the story happened when Hurricane Maria was tracking over P.R., in the movie they had non stop lightning & thunder

[ozonepete]

SLIDER 1min MESO

https://rammb-slider.cira.colostate.edu/?sat=goes-16&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=mesoscale_01&p%5B0%5D=band_02&x=784.9517059326172&y=777.4090881347656

I don't see any significant shear, what am I missing?

There is very little so you're not missing anything.

Did everyone read the last Discussion from Stewart? It isn't shear, but dry air to the west over inland Texas getting sucked in on the west/northwestern side. But it looks like a complete eye is almost there now. As Aric just noted the towers are now wrapped around the SW side and it looks about to close off the eye. You can see a gradual increase in the convection on the western side close to the center as Gulf moisture is swirling around the northern side and rushing southward down the Texas coastal plain, That's allowing the whole western environment to moisten up. If t can get a complete round CDO today, then it could RI tonight or early tomorrow.

[Aric Dunn]

oh boy.. here we go..

also looks like it has started moving just a little south of west..

[TeamPlayersBlue]

I think this shows that it isn't quite stacked yet
Those two new hot towers are curved to the right. They are over the center. The dry slot (not an eye) was misplaced slightly to the east

https://www.tropicaltidbits.com/sat/images/goes16_vis_goes16-meso1_20200724185734.jpg

Screaming eagle.... i finally understand why they call it that. I see it now.

[NDG]

SLIDER 1min MESO

https://rammb-slider.cira.colostate.edu/?sat=goes-16&z=2&im=36&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=mesoscale_01&p%5B0%5D=band_02&x=784.9517059326172&y=777.4090881347656

I don't see any significant shear, what am I missing?

It is/was mid-level shear. So you have a situation where the cirrus seems fine and the lower clouds as well, but the middle is missing. I remember many years ago when Derick Ortt had a great post on it here.

It was the mid level shear as you said but it has not subsided to near 5 knots, but as always it takes a while to get rid of the dry air that entrained into the northern quadrant of the storm.

[Rgv20]

Hanna is looking ready to take off...

[Aric Dunn]

full moisture loop is closed.. lets hope it runs out of time.. but I dont think we are getting away with just a TS..

[TexasF6]

Aric, I wonder which quasi-eye wall becomes dominate? She's going to take off, IMHO!

[Aric Dunn]

low level cloud deck between the west side of the circ and the coast has drastically thickened. looks like convection is about to fill in..

[tolakram]

Saved loop

[Aric Dunn]

Aric, I wonder which quasi-eye wall becomes dominate? She's going to take off, IMHO!

where ever the strongest mid level vorticity and convection that build up through it. its happening fast now.

[Nimbus]

Convective burst as we speak but hopefully that won't be followed by any kind of RI before landfall.

[Aric Dunn]

3 of the surface obs. NW quad, NE and SE quad all showing sustained in the mid to upper 40s winds. away from the center.

also pressures are 1002 well away from the center..

this might be down to 996mb

it has also been moving wsw for the last hour or so..