ATL: TROPICAL DEPRESSION HENRI (10L)

[wxman57]

It does look more impressive on the latest satellite. And a nearby buoy pressure fell 2mb. But it's going to be a battle with shear, as with other systems in that area this season. 12Z GFS takes part of it northward and much of the low-level vorticity westward to Honduras on the 13th.

[Blown Away]

Everybody keeps saying this is going into the Caribbean, models suggesting NE of the Caribbean.

[Blown Away]

The 12z CMC has a weak system moving over Puerto Rico and ending in the northern Cuban coast.

http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation

That run seems reasonable to me.

[HURAKAN]

Latest

[wxman57]

Pressure just rose 1/2 millibar at that nearby buoy, a good sign. Better than if it was falling, anyway.

[Aric Dunn]

With the nearby buoy obs and latest visible. the developing center is likely slightly farther north the best track at about 14.5N
The SSE winds at the buoy dont really support a center to its west..

[gatorcane]

Not surprised about the code orange at all as it slowly is organizing.

I expected it would be orange by 2pmEST as I posted earlier today.

12Z GFS zonal shear forecast shows decreasing shear along the path of this invest:
http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... =Animation

[gatorcane]

bTW, it does appear most members on this board have written this season off. If this were August and we saw this thing, there would be a 10,000+ page thread on it.

[wxman57]

That shear chart does indicate increasing low-level shear beyond 72 hours, though. Prime conditions for development will be the next 2-3 days, as indicated by most model guidance. As I look at all the model plots, I see that they're all forecasting a ridge to build to the north of the system by Wednesday, forcing it west and even south of west Thursday-Saturday. Question is - will there be anything left of it by the time it nears the NE Caribbean on Friday? HWRF has it steadily weakening by Wednesday. Of course, it also has it at TS strength of 38 kts as of 18Z today.

ftp://ftp.ncep.noaa.gov/pub/data/nccf/c ... .stats.tpc

[wxman57]

bTW, it does appear most members on this board have written this season off. If this were August and we saw this thing, there would be a 10,000+ page thread on it.

I was thinking the same. One good thing is that we're not seeing any indications that this has much potential to become a hurricane. So it may just be a heavy rain and squall threat for the NE Caribbean.

[gatorcane]

bTW, it does appear most members on this board have written this season off. If this were August and we saw this thing, there would be a 10,000+ page thread on it.

I was thinking the same. One good thing is that we're not seeing any indications that this has much potential to become a hurricane. So it may just be a heavy rain and squall threat for the NE Caribbean.

Wxman thanks do you see this moving north of the Caribbean as the ECMWF suggests?

[Aric Dunn]

I would not rule out some RI once we get the center well established.. it still has at least 48 hours of favorable conditions... hurricane is still quite possible in the short term but as for anything left by the time it gets to the carribean thats a different story ..

[gatorcane]

Can somebody explain what "unfavorable conditions" are in front of 91L? Sorry for my ignorance, but I'm looking at the WV loop and see that the wind shear that we have been seeing ripping through the Caribbean has finally let up.

I can say this because I don't see any high-clouds racing off to the ENE that I have been seeing the past 6 weeks or so. Is it dry air that should kill 91L?

http://www.ssd.noaa.gov/goes/east/tatl/loop-wv.html

[Aric Dunn]

Can somebody explain what "unfavorable conditions" are in front of 91L? Sorry for my ignorance, but I'm looking at the WV loop and see that the wind shear that we have been seeing ripping through the Caribbean has finally let up.

I can say this because I don't see any high-clouds racing off to the ENE that I have been seeing the past 6 weeks or so. Is it dry air that should kill 91L?

http://www.ssd.noaa.gov/goes/east/tatl/loop-wv.html

the biggest issue will be shear down the road as the trough pulls off the east coast a huge ridge is forecast to build in at all levels which should in part northwesterly shear.. so watch the evolution of that feature and how far south it dives..

[cycloneye]

Below is a portion of this afternoons discussion from the NWS San Juan talking about this wave.

DURING THE LATTER PART OF THE WEEK AND INTO THE UPCOMING WEEKEND
MODEL SUGGEST A FAIRLY ACTIVE TROPICAL WAVE TO APPROACH THE LESSER
ANTILLES AND ENTER THE EASTERN CARIBBEAN BY SATURDAY...THEN MOVE
ACROSS THE LOCAL REGION THROUGH SUNDAY. IF THIS PANS OUT AS
SUGGESTED BY THE LATEST GFS MODEL GUIDANCE...THEN WE CAN EXPECT
INCREASING CLOUDINESS WITH SHOWER AND THUNDERSTORM ACTIVITY OVER
THE UPCOMING WEEKEND. AS ALWAYS WILL CONTINUE TO MONITOR AND ADJUST
FORECAST AS WE GET CLOSER TO THAT TIME.

http://forecast.weather.gov/product.php ... glossary=1

[gatorcane]

Can somebody explain what "unfavorable conditions" are in front of 91L? Sorry for my ignorance, but I'm looking at the WV loop and see that the wind shear that we have been seeing ripping through the Caribbean has finally let up.

I can say this because I don't see any high-clouds racing off to the ENE that I have been seeing the past 6 weeks or so. Is it dry air that should kill 91L?

http://www.ssd.noaa.gov/goes/east/tatl/loop-wv.html

the biggest issue will be shear down the road as the trough pulls off the east coast a huge ridge is forecast to build in at all levels which should in part northwesterly shear.. so watch the evolution of that feature and how far south it dives..

Right but usually if a system gets underneath a building ridge from the North such as this one, that would be favorable for development...

OK, let's see how it pans out but not see anything yet that will kill of 91L yet.

[Aric Dunn]

Can somebody explain what "unfavorable conditions" are in front of 91L? Sorry for my ignorance, but I'm looking at the WV loop and see that the wind shear that we have been seeing ripping through the Caribbean has finally let up.

I can say this because I don't see any high-clouds racing off to the ENE that I have been seeing the past 6 weeks or so. Is it dry air that should kill 91L?

http://www.ssd.noaa.gov/goes/east/tatl/loop-wv.html

the biggest issue will be shear down the road as the trough pulls off the east coast a huge ridge is forecast to build in at all levels which should in part northwesterly shear.. so watch the evolution of that feature and how far south it dives..

Right but usually if a system gets underneath a building ridge from the North such as this one, that would be favorable for development...


72 hours gfs 200mb winds.. notice the nnw winds coming behind the trough just before the system gets pushed back sw in the models it runs into very high upper winds..


it will be building .. but not over it.. it will be coming in behind the trough..
OK, let's see how it pans out but not see anything yet that will kill of 91L yet.

it will be building .. but not over it.. it will be coming in behind the trough..

[gatorcane]

18Z NAM shows it still fairly organized just NE of the Leewards with that building ridge to the NW:

[Aric Dunn]

The placement will be everything.. farther north more shear ..

[Aric Dunn]

I do have to say with recent developments today I would not be surprised to see TS tomorrow ..

there is a strong curved banding feature trying to take shape ..




I wish SSD had the floater up