It's west right now out of great disorganization and weakness. There is nothing for mid/deep layers to pick up. The COC is separate from the cloud mass. My slightly educated guess is that the Northern steering takes Emily if Emily gets it's act together quickly (shear will dissipate soon letting Emily recoup meandering thunderheads), otherwise a languishing Emily floats westward. There's a lot of room to turn North, but the longer Emily waits, the closer to CONUS anything gets. I think the best scenario is that Emily never gets her act together, and she floats as a diffuse large TS over drought ravaged areas. That's wishcasting, but at least in a benevolent way.


8:00 PN tracking data in: Emily is stationary. There's not enough steer anywhere to do anything but float...
The fork in the steering btwn West and North is west of Haiti.

If shear is low, diurnal maximum will be interesting. Nothing like a stationary system.

Ok, well, now here is my forecast for the next 24 hours.


I should note, the storm has had a bit of a hiccup the past few hours, as some re-organization has given a bit of a "relative stall".

The LLC as been pulled back slightly under the convection blob, as happens sometimes with weak systems, so there was a tad of a reset in westward progression.

Nevertheless, the steering environment favors my previous forecast fairly well, though the "stall" will require me to revise my position eastward a tad, but still west of the NHC cone once again....

The over-all motion of the entire system is about the same as always.


Position:

My "target" is 18N and 75.5W @ 8pm Eastern, 7pm central August 4th.


Plus or minus a few tenths of a degree in each axis...

Intensity:

I call for an AVERAGE of 5kts of intensification per 6 hour period between now and then, so in 5kts increments (rounding mph to nearest 5):

now: 45kts (50mph)
6hrs: 50kts
12hrs: 55kts
18hrs: 60kts
24hrs: 65kts (75mph)

WITH a margin of error after 24 hrs being +10kts to -5kts...

Thus, after 24hrs, the winds will be between 60kts (near 70mph) and 75kts (85mph). My most likely target, again, being 65kts at 24hrs...


Shear over the region will be dropping some over night and into tomorrow.

Additionally, heat content in the ocean is significantly higher in the region the storm is entering.

Finally, the storm is leaving the "John Hope" zone, or dead zone for developement and intensification of weak cyclones, and instead entering the near-perfect Western Caribbean zone.


Based on the most recent observations, combined with climatology and history, and simply looking at the steering in RGB satellite imagery, I do not believe these intensities will be sufficient to cause the storm to turn north very much.


Additional information will be available then.

Only 4 storms in recorded history in a similar location and same month have managed to miss the mainland continent, suggesting it takes an exceptional steering feature to bring a storm up and re-curve it from this location. We do not have such a feature...

http://classic.wunderground.com/tropical/t...mo.html#a_topad


So anyway, I'll be back tomorrow to re-analize the situation, and see how well this forecast has panned out...

The stall has been annoyingly long, and has delayed everything by around 12 to 15 hours.


Still, even with the stall, the average motion (the vector, not the speed,) of the LLC is almost exactly in line with the forecast I gave 12 hours ago, it's just going to be delayed by 12 to 15 hours, I think.


Average motion of the center for the past 15 hours has been:

0.2N and 0.8W, for a ratio of 1/4, this gives a bearing of 14.5 degrees.


In the past 3 hours, the storm actually moved SSW, or 0.2 S and 0.1 W, though "officially" it is still regarded as "nearly stationary."


The monsoon trough has gained amplitude, shortened period, and become more concentric with Emily's LLC over night.

http://rammb.cira.colostate.edu/products/t...01108020714.GIF


This is one reason this storm does not "turn" easily, and only wobbles. It is imbedded inside a double envelope, inside one of the largest air masses in the hemisphere. These types of systems, (such as Alex,) tend to just keep going west, and drift only a tenth or so north every several hours. They are so massive that ordinary steering features have little influence on them. While the LLC may wobble around a bit inside there, it isn't going to go flying off in some tangent direction, at least not without significant intensification to gain the pole-seeking effects of the coriolis effect...

So on a synoptic scale, the storm is more organized than it has ever been.

On a local scale, not much has changed, except there is more convection on the western side of the storm than 15 hours ago, suggesting some room for intensification if it can get some breathing room from the close call with the islands.


Busted track alibi:

Nobody else, not even a model, anticipated a stall of any kind. In fact, the NHC and most of the modeels was forecasting a speeding up to around 17kts before this happened.


Busted Intensity alibi:

Because it never crossed 73W, my assumptions about historical averages and water and atmosphere conditions were delayed by 12 to 15 hours.

====


New track:

Still calling for 18N 75.5W, just move it back 12 hours.

So tomorrow, August 5, at 8am EDT, Emily will be near 18N 75.5W.


Intensity:

Based on my track assumption, I'll still go with the +5kts per 6 hours AVERAGE intensification, assuming the stall is ending presently, which Satellite suggests may be happening.

Now: 45kts
6hrs: 50kts
12hrs: 55kts
18hrs: 60kts
24hrs: 65kts

Margin of error is the same @ 24hrs (offset by 15 because of the stall.)

-5kts to +10kts @ 24hrs

or

60kts to 75kts @ 24hrs, being 8a.m. EDT, August 05...

Like I said before, until there is an actual stacked cylinder into the 700+ mb level, the strong northern turn can't happen. The storm is nearly exactly what the NHC has predicted in strength, and where it should be since it hasn't tightened up enough to strengthen. The "50kn" winds are confined to a tiny area. NHC needs no alibi for their unbusted prediction.

Avila is the best tropical forecasting mind in the world, and when he says the models are "seeing something not apparent to him" (rough quote), that is a spicy statement. This means there are as-of-now unseen aspects of the variables that when they synergize, are supposed to do what the models suggest. That Avila is for now disregarding the models' pov in the official forecast is very interesting. That he is demonstrating his humility in his statement is not surprising. It's also a statement that currently indicates more guesswork than usual. The most difficult storms to predict are the ones that are not in an environment providing strong steering patterns. When this occurs, any one of the minor players that would normally not have a hand in the mix, can become the new steering force. And predicting that is not dissimilar to finding the needle. It is guesswork, a roll of the dice. The 'strongest looking' player may not be that at all to the system. Mass of the system in different layers must be taken into account. We are nowhere near the point that exact forecasts can be made, which is why both you and NHC were not right on, but NHC was closer than you. Everything you have commented on is not lost on NHC, you know that, right?

Be humble.