Strong Tropical Wave Emerging off Africa (INVEST 99L is up)

[Miami Storm Tracker]

Nothing is ever guaranteed in the tropics but as we know we are entering the active part of Hurricane season. So this should be watched monitiored and tracked to see what develops and where it may go.

[Nimbus]

We always used to wait a few days to see how much these waves settle down.
Lift from the mountains always increases convection in that area, but Kelvin wave synch sounds like a viable model consideration.

[Hammy]

This looks like the strongest wave we've seen come off so far. As long as it can maintain a moisture envelope, I'd be surprised if this doesn't develop down the road at some point.

What does he mean? That it is a false alarm?

Probably not. This is a case of a AEW being amplified by convection over western Africa (Guinea Highlands) vs eastern Africa (Ethiopian Mtns) leading to the models picking up on it later.

So that explains why the models have been slow to pick up on whatever might form.

[Miami Storm Tracker]

Mod's please feel free to kill this post or put it where it belongs. I hame have a bit of a struggle or confusion. One post talks about a wave coming off Africa, and long range models show it develops and tracks to the Islands then possibly the SE US. But then again other post discuss it going way south and West. so any clarification of this post would be much appreciated.

[Hurricaneman]

Who thinks the chances get upped in the next outlook to 20/40 or 50

[Hurricaneman]

Mod's please feel free to kill this post or put it where it belongs. I hame have a bit of a struggle or confusion. One post talks about a wave coming off Africa, and long range models show it develops and tracks to the Islands then possibly the SE US. But then again other post discuss it going way south and West. so any clarification of this post would be much appreciated.

it's mostly the difference in model runs and where they place it

[Hurricaneman]

I like the look of this one already and this definitely has some serious model support, wouldn't be surprised if this becomes 99L in the next 12 hours or less

My thoughts are I feel this could be a hurricane approaching the lesser Antilles but that will be determined by sometime early next week possibly

[USTropics]

Very healthy looking wave:

[Hurricaneman]

The low closes off at 36 hrs on the 0zGFS and is down to 1013mb at 48 and down to 1010 at 54

[Hurricaneman]

0zGFS starts the development phase at 78 hrs and has the pressure down to 1009

[floridasun78]

look dry air now left Atlantic ocean or very less that what kill other systems

[TropicalAnalystwx13]

Convective feedback is a far overused term, but here's an example.

[weathaguyry]

The 18zGFS has this hitting Long Island and , Rhode Island, and eastern Massachusetts at 324 which means usually they're safe but who knows

With the way the ridge is setting up with a trough getting sharper as it moves east, it could provide an opportunity for something like an Irene to occur, which is not good, because we definitely do not need a hurricane on Long Island any time soon

[Hurricaneman]

0zGFS has it down to 1007 at hr 90

1006 at 102

[tarheelprogrammer]

GFS 10mb weaker at hour 114.

[Alyono]

MUCH weaker on the GFS

Model is not one that I give much weight to. It is about as useful as the NAVGEM

[Siker]

UKMET very similar to its 12z run:

NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER 72 HOURS
FORECAST POSITION AT T+ 72 : 12.6N 37.9W

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 06.08.2017 72 12.6N 37.9W 1011 28
1200UTC 06.08.2017 84 13.1N 40.6W 1009 31
0000UTC 07.08.2017 96 13.3N 43.4W 1008 33
1200UTC 07.08.2017 108 13.3N 46.7W 1007 33
0000UTC 08.08.2017 120 13.4N 50.0W 1007 34
1200UTC 08.08.2017 132 13.6N 53.7W 1004 37
0000UTC 09.08.2017 144 14.3N 57.7W 1002 40

[Dylan]

The 0z GFS might be weaker on this run, but the synoptic patten is a dangerous one historically, and promotes strengthening.

[Hurricaneman]

I'm thinking with the other modeling that the GFS is pulling it too far north, when in doubt go with the Euro

[USTropics]

For what it's worth, the CMC is much stronger this run: