ATL: GERT - Post-Tropical - Discussion

[Bocadude85]

http://i.imgur.com/2pjQMLY.gif

There must be some feature that will be significantly slowing the forward progress of 99L very soon because the 12z Euro has 99L crossing @20N/58W in 48 hours... 99L appears to be flying at a decent clip to the WNW and appears to be crossing 53W now...

The Euro could be just forecasting a stronger vorticity to develop to the north of the surface vorticity being tracked on vis satellite.

The 18Z GFS seems to be showing some kind of vorticy developing farther north and taking over just like the 12z Euro showed.

[Kingarabian]

One caution, 5 days out, there was almost no ensemble support for Matthew having a major impact

They verified well then if you're talking about a major hurricane making landfall.

the ensembles said little chance of the storm passing within 125 miles of the coast. Matthew took the extreme western edge of the probability swath.

Not technically a fail, but something that should happen only 5-10% of the time

Right now the probabilities seem identical except the mean is closer than the 125 miles margin east of the Carolina's.

[Kingarabian]

Quite the dry air in front of it...

[PTrackerLA]

Also think those huge shifts in Matthew happened after it was a tropical storm. We just have a disturbance now I don't think any future track is set in stone.

[txwatcher91]

From what I can tell, the 18z GFS seems a bit stronger with the vort (compared with 12z) and takes a similar track as the Euro and CMC, but it still doesn’t develop it.

[Kingarabian]

From what I can tell, the 18z GFS seems a bit stronger with the vort (compared with 12z) and takes a similar track as the Euro and CMC, but it still doesn’t develop it.

GFS is not too crazy with its solution. I posted in the discussion thread that the battle for 99L may just be beginning with all that dry air.

[floridasun78]

starting look llc at 54-53 w 16-17 north and starting look better today too

[floridasun78]

Quite the dry air in front of it...

http://i.imgur.com/RLTrwkJ.png

that moving west with ull

[bghowie]

I think Matthew did make landfall in the low country of SC.

[txwatcher91]

From what I can tell, the 18z GFS seems a bit stronger with the vort (compared with 12z) and takes a similar track as the Euro and CMC, but it still doesn’t develop it.

GFS is not too crazy with its solution. I posted in the discussion thread that the battle for 99L may just be beginning with all that dry air.

It certainly will be interesting to see how this unfolds. Euro and CMC are bullish and other models have weak development, GFS is stronger with the vort but doesn’t develop it. It also seems to move it a little faster.

[txwatcher91]

Another aspect to consider, if this moves faster than modeled and/or doesn’t reform further north, then that would likely shift the track west. Being that we are 6-7 days out from potential impacts, a lot can change between now and then. It wouldn’t take much of a change to shift the track west.

[OuterBanker]

I remember correctly didn't the earlier GFS models have a monster in Miami while the Euro was taking a weaker system into the Caribbean shredder? Seems now the have flipped. BTW, while no one is looking it seems to me that for the first time the mid level convection is lining up with the llc. Or is it just me?

[JtSmarts]

I think Matthew did make landfall in the low country of SC.

Landfall was 5 miles south of McClellanville at 85mph.

[Kingarabian]

18z GFS hours 24-144:

[Jerry]

Does the dry air out in front of the wave affect it as bad as behind the wave? I thought I have read on this board over the years that dry air behind the wave will hinder development.

[RL3AO]

Does the dry air out in front of the wave affect it as bad as behind the wave? I thought I have read on this board over the years that dry air behind the wave will hinder development.

When dry air catches a wave from behind, that means strong mid-level wind shear is with it too. In this case, you have some dry air that's moving along in tandem with the wave.

[floridasun78]

Does the dry air out in front of the wave affect it as bad as behind the wave? I thought I have read on this board over the years that dry air behind the wave will hinder development.

When dry air catches a wave from behind, that means strong mid-level wind shear is with it too. In this case, you have some dry air that's moving along in tandem with the wave.

good for 99l or bad?

[cycloneye]

Gaining more convection.

[Kazmit]

Up to 0%/40%

1. A trough of low pressure located about 650 miles east of the
Leeward Islands continues to produce disorganized showers and
thunderstorms. Environmental conditions are expected to remain
unfavorable for significant development during the next couple of
days. However, environmental conditions are forecast to become
a little more conducive for development late this week while the
system moves generally west-northwestward at about 15 mph over the
western Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

[Nimbus]

Does the dry air out in front of the wave affect it as bad as behind the wave? I thought I have read on this board over the years that dry air behind the wave will hinder development.

When dry air catches a wave from behind, that means strong mid-level wind shear is with it too. In this case, you have some dry air that's moving along in tandem with the wave.

good for 99l or bad?

The Bermuda high is centered near 30N -60W so moisture to the NE of 99L should be entering the circulation tomorrow.