Two African waves, 92L and 93L, worth watching

By: Dr. Jeff Masters , 2:59 PM GMT on August 11, 2011

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An African wave is near 13°N 35°W, about 700 miles west-southwest of the Cape Verde Islands. This system, (Invest 92L), is moving west to west-northwest at 10 - 15 mph, and has the potential to develop into a tropical depression or tropical storm before arriving near the northern Lesser Antilles Islands early next week. Recent visible satellite loops show that 92L has less heavy thunderstorm activity near where it is trying to develop its circulation center than yesterday. Water vapor satellite loops that a large area of dry air lies just to the west of 92L, but the atmosphere in the immediate vicinity of 92L is moist. Even so, the decline of heavy thunderstorm activity since yesterday implies that dry air is probably working its way into 92L. The SHIPS model and University of Wisconsin CIMSS wind shear analysis are showing moderate wind shear of 10 - 15 knots affecting 92L. Sea surface temperatures are 26.5° - 27°C, which is very close to the 26.5°C threshold usually needed to support a tropical storm.


Figure 1. Morning satellite photo of Invest 92L and Invest 93L.

Forecast for 92L
Low to moderate wind shear of 5 - 15 knots is predicted along 92L's path over the coming three days, which should allow the storm to organize, assuming it can shut out any incursions of dry air that might intrude. The latest 00Z and 06Z model runs of the four best models for predicting tropical storm formation (GFS, ECMWF, NOGAPS, and UKMET) show weak development or no development of 92L, and NHC gave 92L a 30% chance of developing into a tropical depression by Saturday morning in their 8am outlook. A steady west to west-northwest motion for 92L is predicted by all of the models, which would put the storm in the vicinity of the northern Lesser Antilles Islands by Sunday. On Saturday and Sunday, 92L is expected to enter a region where an upper-level low pressure system will bring high wind shear of 20 knots to the storm, which should slow development. This upper-level low is also expected to turn 92L more to the northwest, so the storm is likely to pass north of the Lesser Antilles, though may pass close enough to give heavy rains to the northernmost islands. It is too early to know if 92L will recurve out to sea and potentially threaten Bermuda, or continue to the northwest towards the U.S. East Coast.

93L
An African wave that emerged off the coast of Africa is near 10°N 22°W, a few hundred miles south of the Cape Verde Islands. This system, (Invest 93L), is also moving west at 10 - 15 mph, and has the potential to develop into a tropical depression or tropical storm before arriving near the northern Lesser Antilles Islands near the middle of next week. Recent visible satellite loops show that 93L has a decent amount of heavy thunderstorms, but this activity is not well organized. There is not much spin associated with 93L yet. 93L is fairly well-protected from dry air to its north and west. The SHIPS model and University of Wisconsin CIMSS wind shear analysis are showing moderate wind shear of 10 - 20 knots affecting 93L. Sea surface temperatures are 27.5°C, which is one degree above the 26.5°C threshold usually needed to support a tropical storm.

Forecast for 93L
Moderate wind shear below 20 knots is predicted along 93L's path over the coming five days, which should allow the storm to steadily organize. 93L is about 600 miles east of 92L, which is close enough that the two systems may interfere with each others' organization. The latest 00Z and 06Z model runs of the four best models for predicting tropical storm formation (GFS, ECMWF, NOGAPS, and UKMET), have only one model, the GFS, that is indicating significant development of 93L. This model brings 93L near the northern Lesser Antilles Islands by Wednesday. NHC gave 93L a 20% chance of developing into a tropical depression by Saturday morning in their 8am outlook. Due to moister air, the potential for less wind shear, and a more southerly track, 93L is probably a greater threat to the Lesser Antilles than 92L.

Jeff Masters

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1859. KEEPEROFTHEGATE (Mod)
Quoting blsealevel:

water vapor upper level and mid level






here is full view

Member Since: July 15, 2006 Posts: 169 Comments: 53296
1858. MTWX
Quoting tropicfreak:
Anyone know which one is 94L, and do we have 95L? Hopefully someone sees this before a troll removes it.

94L is the system that has moved around the Bermuda high heading to intercept 92L, while 95L is the little smudge off of the east coast heading toward Europe.
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Quoting Floodman:


Sounds like they're preparing for something major


the models show the bulk of the large swell passing south of pr but not by much ill keep checking the NOLA forcast models as they r updated leter on in the weekend but it is interesting
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Quoting nigel20:

94L is nw of 92L and 95L is nw of 94L



Thanks!
Member Since: September 2, 2006 Posts: 110 Comments: 6874
Quoting Floodman:


This is why buhdog is beloved amongst bloggers, his flair for the potentially true but seemingly ridiculous

you got that right batman...love critter casting... and btw...when the fiddlers disappeared from here when emily was crossing the bahamas and near FL...we ended up with massive waves and bad bad rips that sat and sunday...looks like the critters knew it was gonna happen...
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Just a few minutes away for the GFS run. Let's see what dramatic solution it comes up with this time around.
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1853. nigel20
Quoting tropicfreak:
Anyone know which one is 94L, and do we have 95L? Hopefully someone sees this before a troll removes it.

94L is nw of 92L and 95L is nw of 94L
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1852. Mucinex
Something needs to get named soon cause I want to break into my supply of hurricane candy.

Also, I can pass a "Neil Frank BuzzCut Hurricane Deflector" under the table if someone needs it.

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Can it already be SEVEN years since Charley?

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Quoting FLdewey:
Dang it someone took ants?

Grrr...

How about a "Don't quote Jason he's on my ignore list?"


No, that's another game entirely...
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1849. Matt74
Quoting Jax82:


Plenty of fuel for the fire, lets just hope a fire doesnt start.
I was at the beach last weekend on the upper tx coast, and that water was like taking a dirty hot bath!
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Quoting NEwxguy:
Ahhh,now we getting into some real forcasting.

I'll see your pumped ridge and raise you two deep troughs.


Two TUTTs and failed recurve
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If the 6Z GFS is correct then the GOM and Texas better closely monitor 93L!!!

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Anyone know which one is 94L, and do we have 95L? Hopefully someone sees this before a troll removes it.
Member Since: September 2, 2006 Posts: 110 Comments: 6874
1844. KEEPEROFTHEGATE (Mod)
Quoting kmanislander:


Hey Flood, long time no see. Not sure if that's because I have been away or you haven't been on or both LOL

A real parade of mischief makers out in the Atlantic. One of them, 92L, looks like dry air is choking it right now with all those outflow boundaries on the entire west side of the circulation. As for the rest, 93L is the one to watch IMO. Not looking too hot right now but that will only help it stay low and chug along to the West, sort of in stealth mode.
mornin kman ya stealth mode is the worse mode come up on ya all of a sudden without warning out of the clear blue sky
Member Since: July 15, 2006 Posts: 169 Comments: 53296
1843. nigel20

93L
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Quoting mrpuertorico:


if you say his name three time while in a tunnel he will appear! Cyclone..... no i wont give in!!

on a weather note LOLA near shore wave models predicting 16+ft swells for northern antilles next week (thursday)


Sounds like they're preparing for something major
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water vapor upper level and mid level




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Quoting aspectre:
1711 CybrTeddy "...95L might be the most immediate threat to develop, as the NHC has tagged it 30% when it has 48 hours IMO to develop."

Hokay, where did you see 95L? Been waiting since you first posted that part, expecting ATCF to post a confirmation. But nothing's showing up.


Link
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Quoting aspectre:
1711 CybrTeddy "...95L might be the most immediate threat to develop, as the NHC has tagged it 30% when it has 48 hours IMO to develop."

Hokay, where did you see 95L? Been waiting since you first posted that part, expecting ATCF to post a confirmation. But nothing's showing up.

ftp://ftp.tpc.ncep.noaa.gov/atcf/tcweb/
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Quoting Buhdog:
I call ants in the house and some crawfish crawling to higher ground.

Link



This is why buhdog is beloved amongst bloggers, his flair for the potentially true but seemingly ridiculous
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Quoting Floodman:


Shhh...speak of the devil and he shall appear...


if you say his name three time while in a tunnel he will appear! Cyclone..... no i wont give in!!

on a weather note LOLA near shore wave models predicting 16+ft swells for northern antilles next week (thursday)
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Darn it got removed.
Member Since: September 2, 2006 Posts: 110 Comments: 6874
Quoting kmanislander:


Hey Flood, long time no see. Not sure if that's because I have been away or you haven't been on or both LOL

A real parade of mischief makers out in the Atlantic. One of them, 92L, looks like dry air is choking it right now with all those outflow boundaries on the entire west side of the circulation. As for the rest, 93L is the one to watch IMO. Not looking too hot right now but that will only help it stay low and chug along to the West, sort of in stealth mode.


Apparently my first response got lost sonewhere...Hey, kman! Been in and out myself though I've been busy and don't typically post much the last few weeks or so...

As for our traffic jam in the Atlantic? You are absolutely correct: the ones that stay small have the greatest chance of missing the predicted turns, continuing westward and causing serious trouble for someone. I dread to think what will happen if something small but organized hits the GOM or the Caribbean low...the potential is pretty disastrous
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1833. SQUAWK
Quoting cloudburst2011:



thats old news scott i been saying that since yesterday morning...


That's old news cloudburst, I been saying that since day before yesterday.
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1832. hydrus
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1831. Buhdog
I call ants in the house and some crawfish crawling to higher ground.

Link

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The 95 Blob looks better than any other. Unfortunately it has only a little time left.
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Quoting tiggeriffic:


pulling another 12hr today...yay me...lol...shoulda come out last night...pot roast with baby taters n carrots for dinner with a side of watermelon n peanut butter cookies with mini reseese cups in em...


I always miss the good meals...I won;t even talk about the 12 hour days

LOL
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1828. hydrus
Quoting Floodman:


Sorry, can't accept herbert box...this is "Questionable Meteorological Terms and Concepts Poker"...however we will playing "Made up out of Whole Cloth Dominos" in a couple of hours
All in....
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Hard times...

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1711 CybrTeddy "...95L might be the most immediate threat to develop, as the NHC has tagged it 30% when it has 48 hours IMO to develop."

Hokay, where did you see 95L? Been waiting since you first posted that part, expecting ATCF to post a confirmation. But nothing's showing up.
Member Since: August 21, 2007 Posts: 0 Comments: 4860
Quoting hydrus:
Good morning Flood...I just noticed it myself. N.E.Texas may get some more..This little guy could effect Cuba..


Already effected our weather here in pr a bit with showers and thurnderstorm flare ups caused by its little cute tail
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Quoting hcubed:


You want tunnels?

He was in full force over at RR's climate blog the other day.

We don't need him here...


Shhh...speak of the devil and he shall appear...
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1821. scott39
93L looks like it will catch 92L, absorb its energy and keep moving W. The Euro has it on a much more southern track than it did. If this stays the same, then I think it would go through the Caribbean threatning Jamaica and the Cayman Islands.
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1820. hydrus
Quoting nrtiwlnvragn:
FWIW 12Z NAM likes 94L (I know not a model)

Link
May end up further west on next model run..
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1819. hcubed
Quoting Floodman:


Okay, so this morning I have seen Fujiwara and Haarp...dare I? I do...HEBERT BOX

Anyone see my Hebert Box and raise me TUNNELS?

LOL


You want tunnels?

He was in full force over at RR's climate blog the other day.

We don't need him here...
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Quoting dc8mech:
all in. i see your ridge, and tunnels, fujiwara, and so called herbert box. and raise you a few ions.


Sorry, can't accept herbert box...this is "Questionable Meteorological Terms and Concepts Poker"...however we will playing "Made up out of Whole Cloth Dominos" in a couple of hours
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well I haven't been on in a little while. Things have been quiet. I have been keeping an eye on the tropics and we now have 4 circles on NOAA page. Three orange (2 40% and 1 30%).

Part of Emily's remnants look like they could be trouble for the Bahamas and possibly the SE coast. I am not sure if this system would be named Emily again since the "low" that was Emily went NE over the North Atlantic.

92L is looking like the best chance to become the next tropical depression but most of the models show the storm re-curving but it is too early to tell. I think the East Coast should keep an eye on this one. This "low" might actually interfere with the "Remnants of Emily" since they are starting to get very close to each other.

There is also an area of "low Pressure" off the SE coast which is expected to move NE. I am not sure on this system becoming a TS since it has little time to do so but it is looking better on the Satellites. I don't see it being a problem for any land areas unless you count the Azores.

Finally, we have 93L which is the scariest of all the systems we have brewing. It is on a path further south than the previous three mentioned above. There are models which show this system making it into the Caribbean. Let me tell you why I think this is the likely scenario.

It looks like 92L will probably develop first into a TS. It is quite possible that this storm interferes with 93L and keeps it weak which would push it on a more westerly path. I think it's location also will help it along into the Caribbean. Now some models show the storm as a big hurricane near Burmuda before hitting Eastern Canada. This is a real concern to me. Any system that gets that close to land in the North East is something to keep a GOOD eye on because any change in the trough and you have the first hurricane in the NE in years. That would be the worst thing that could happen right now with the economy. Bottom Line: 93L is the one to really watch.

Oh and one last thing. It looks like the tropical train has started. Think the activity from here on out will be breath taking. That is good for all of us tropical loving folks. Lets just pray none plow through the oil fields in the gulf.



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Quoting Floodman:


Alright, you win!


Hey Flood, long time no see. Not sure if that's because I have been away or you haven't been on or both LOL

A real parade of mischief makers out in the Atlantic. One of them, 92L, looks like dry air is choking it right now with all those outflow boundaries on the entire west side of the circulation. As for the rest, 93L is the one to watch IMO. Not looking too hot right now but that will only help it stay low and chug along to the West, sort of in stealth mode.
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1815. MTWX
Quoting hydrus:
I think it happened last night..It has all but dissipated..More rain is certainly possible tho..

Check out the rainfall totals for yesterday!

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FWIW 12Z NAM likes 94L (I know not a model)

Link
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Quoting jeffs713:

HAARP has been used to influence hurricanes traveling through the Hebert Box, potentially causing them to exhibit a Fujiwara effect and take a route over the storm-killing Tunnels.
on the deforested mountains of Hispaniola.
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Quoting jeffs713:

HAARP has been used to influence hurricanes traveling through the Hebert Box, potentially causing them to exhibit a Fujiwara effect and take a route over the storm-killing Tunnels.


Alright, you win!
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1811. Jax82
Quoting Matt74:
Thats a recipe for trouble if anything gets in there!


Plenty of fuel for the fire, lets just hope a fire doesnt start.
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I raise a pinhole eye and a shower curtain
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1809. hydrus
Quoting MTWX:

Looks promising on the IR, but there isnt squat on the radar.

Link
I think it happened last night..It has all but dissipated..More rain is certainly possible tho..
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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