Hurricane Maria: NNW Of Bermuda Hurricane Watch Issued

[GaWx]

Fwiw, 9/5 runs for 95L updated for the 18Z GFS recurve/miss:

GFS:

0Z 9/5 GFS recurve 72W on 9/12 as very weak low.

6Z 9/5 GFS hits S FL 9/14 as a weak low.

12Z 9/5 GFS hits Cape Cod/ME 9/16 after reaching 77W on 9/13.

18Z 9/5 GFS recurves near 69W 9/12.

Euro:

0Z 9/5 Euro gets to C Cuba 9/14 when the run ends.

12Z 9/5 Euro gets to 79W just off SE FL 9/14 as a very weak low and then recurves E of the SE coast

[Hurriplane]

[Eyewall2005]

Not all that suprised with most recent models trends with this semi perminent trof that wont budge.

Here are some 00z models trending even futher north.

Some early 00z plots

[GaWx]

Why do the BAM's continue showing a WNW move from the start? Is this already moving that much north of west? Otherwise, they're out of whack.

[andyhb]

Still looks messy on the TPW, but I'm guessing the circulation is located around 10N, 30W at the end of the loop.

[Hurriplane]

A S/FL hit, but very very weak, just an open wave.

[Eyewall2005]

00z GFS appears to recurve this well east of U.S.....So much for a stronger ridge its nearly non-existant.

[CUmet]

The 00z GFS initialization of 95L's center seems suspect to me. It has it near 12/37 at 06z, but based on satellite imagery and current NHC estimates it's nowhere near that far NW yet.

[GaWx]

The 00z GFS initialization of 95L's center seems suspect to me. It has it near 12/37 at 06z, but based on satellite imagery and current NHC estimates it's nowhere near that far NW yet.

What you're saying appears to make sense. If it is too far NW by several degrees, that could easily be enough to allow it to not get fully caught in the trough that gets it near 69W on 9/13-4 as per the 0Z 9/6 GFS. If that weren't to fully get it and if the subsequent 0Z run's 30-40N W ATL/US E coast 9/15-18 ridging were to still verify (it was also on the 9/5 6Z and 18Z GFS runs), I would think that would mean a trapping scenario and a turn back to the W to WNW/sig. risk to the SE US. These types of alternative scenarios weren't even being considered with Katia by many due to persistent troughing with hardly any letup in the modeling's troughing. Now we have a potentially different ballgame.

I also have a problem with this evening's BAM initializations. The BAM's move 95L WNW immediately, which looks quite suspect.

[phil882]

Pretty broad center still, but it looks be centered at 10.5N. Nice dual feeder bands.

[phil882]

The ECWMF remains consistent... into the Central Caribbean at 120 hours.

[phil882]

Invest 95L looks great right now, but it has a pretty rough future ahead of it. I've split my thoughts up into three parts that are build on one another so things can be better understood.

1. First of all you can see on water vapor that there is a pretty significant trough in front of the system. This feature is moving to the west with time, but if 95L speeds up at all, it will start to induce shearing. This is crucial because its directly tied in with my second point.

2. Second has to deal with Kelvin waves. Does anyone remember the "unexpected weakening" of Katia last week? Well looking back at the actual observed data, you can see there was actually a pretty significant +OLR anomaly associated with the subsident phase of a kelvin wave that traveled over Katia. This increased the shear over the system by speeding up the low level flow in the proximity of an upper level trough to the NW, while also increasing the convergent upper level flow inducing subsidence for a 24-48 hours. Katia was not able to recover until it slowed down. Now lets focus on Invest 95L. Below, you can see that it seems the same thing is about to occur. Already we have the upper level trough out to the NW of Invest 95L. The storm is currently under a weak convectively coupled Kelvin wave (this is a projected anomaly so that's why it looks so faint since the signal is dampened out the further you go forward in time due to uncertainty) which is enhancing convection in the short term, but its about to come under the subsident phase which will speed up the low level flow and induce shearing through the fact that the low level flow will be moving faster than the upper level flow. So even though the upper level flow might "appear" to be favorable, the low level flow forces the low level circulation to run out ahead of the convection, decoupling the low and mid level circulations, and causing the storm to run right into the upper level trough to the west. This leads to my third point.

3. Interestingly enough, this is exactly what the ECWMF is forecasting beyond 24 hours. While the 200mb flow appears to be favorable, note the tilting that occurs between the 850mb center and the 500mb center. This is directly because the low level flow speeds up too quickly and the upper level flow can't keep up, and 95L moves in head first into the upper level trough to its west. Its actually nice to see for once that a global models might be trying to depict a kelvin wave impact on a tropical cyclone, and its certainly worth watching the next few days to see if the ECWMF is getting the forecast correct or not.

So basically if 95L wants to develop, it better do it in the next 24-36 hours, because conditions are going to become more hostile for development beyond then.

[GaWx]

IF 95L is truly only close to 32.5W as of 6Z, then I could say with certainty that the 0Z and 6Z GFS runs are initializing 95L quite a bit too far west...about 4 degrees. That 4 deg. may be quite crucial as both the GFS and Euro runs of the last few cycles are insisting on a pretty strong and persistent ridging pattern setting up along the U.S. east coast around 9/15, which, if accurate, would be a major pattern change. This means that a slower, more easterly position of 95L vs. the last two gfs runs may mean it would actually miss that trough that takes it well east of the US and get trapped underneath the building ridge around midmonth. IF that were to occur, 95L would likely make a move toward FL or some other portion of the SE US soon afterward. So, this is why what appear to be too far west gfs initializations may mean that the latest 95L recurves on the gfs may verify to be incorrect.

Even if 95L were not to be trapped or not to still exist, that new ridging pattern starting around midmonth would be a rather ominous sign for increased risk of a SE US or US Gulf

coast TC landfall based on history. Persistent and nearly stationary relatively high pressure in that position makes it quite conducive for low pressure to exist and strengthen underneath as well as

move toward the SE US if there is not already an existing TC. This possibility is made more believable by the current weak La Nina (based on history).

[MarkSC]

The low is very close to a depression now (70% per NHC), so the weaker, southern solution of the Euro is suspect imo.

[Srain]

The low is very close to a depression now (70% per NHC), so the weaker, southern solution of the Euro is suspect imo.

So do you think the shear forecast is not correct?

[MJO812]

Latest tracks

[Eyewall2005]

No persistent high pressure over the eastern USA and the western Atlantic.

[donsutherland1]

The ECWMF remains consistent... into the Central Caribbean at 120 hours.

It does.

Finally, another system forms in the Bay of Campeche and then tracks northward through the GOM.

[GaWx]

No persistent high pressure over the eastern USA and the western Atlantic.

Not yet, but the GFS/Euro are strongly hinting at that starting around 9/15.

[MJO812]

12z GFS is a fish storm, thanks to the huge trough in the east.

[GaWx]

12z GFS is a fish storm, thanks to the huge trough in the east.

1) I still think that the GFS is too far west with the initialization of 95L with it being near 37W for the 12Z run. That could make all of the difference regarding a recurve as a later move to the W ATL may mean the trough has lifted before taking 95L.

2) That being said, the 12Z GFS doesn't have the persistent, impressive ridging for 9/15+ that the prior GFS and Euro runs had. I'll see if the 12Z Euro hints at the same thing.

[Eyewall2005]

12z models...

[snowNH]

12z models...

That looks like a pretty good consensus this far out for N of hisp.

[Srain]

Meh. If the intensity happy Hurricane models are keeping this weak, I'd bet 'a dollar to a donut' this heads W of 50 before developing…

That looks like a pretty good consensus this far out for N of hisp.

12Z HWRF suggests absolutely no development. Consensus?

[Srain]

12Z HWRF suggests absolutely no development.

Add the GFDL to that as well.

[GaWx]

95L on the 12Z 9/6 Euro hour 6 map is near 10N, 36W, which is about 3.5 degrees E and 1 degree S of the 12Z 9/6 GFS's ~11N, 39.5W or ~275 miles ESE of the 12Z 9/6 GFS. The 12Z Euro's initial position looks to be more accurate imo. It is also ~50 miles east of the comparable 18 hour 0Z Euro position. Let's see how this plays out.

[Cheeznado]

95L on the 12Z 9/6 Euro hour 6 map is near 10N, 36W, which is about 3.5 degrees E and 1 degree S of the 12Z 9/6 GFS's ~11N, 39.5W or ~275 miles ESE of the 12Z 9/6 GFS. The 12Z Euro's initial position looks to be more accurate imo. It is also ~50 miles east of the comparable 18 hour 0Z Euro position. Let's see how this plays out.

Euro to 150- very weak, somewhere near Hispaniola- 144 Ukie north of Hispaniola by a bit but farther south than the GFS/CMC

[blazess556]

Invest 95L has formed into Tropical Depression 14.

invest_RENUMBER_al952011_al142011.ren

[Cheeznado]

New Euro keeps this very weak all the way- and then begins a recurve in the SE Bahamas, this run with be a miss.

[MarkSC]

The Euro upper pattern is much different than the GFS. It shows a strong Atlantic ridge, which allows the low to get pretty far west and remain south, before a trough picks it up and recurves through the Bahamas. GFS shows the persistent east coast trough remaining in place so the storm recurves near 60 west. To complicate things, 96L is a player for the Euro but not for the GFS, which keeps it trapped in the BOC for an eternity.