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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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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1808. dc8mech
all in. i see your ridge, and tunnels, fujiwara, and so called herbert box. and raise you a few ions.
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Quoting redwagon:

Nothing in Austin yet. Patiently waiting for another Hermine.


It was 8:45 UTC (a little over 6 hours ago). Nice blow up of convection overnight but it's since waned.
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1806. hydrus
Quoting Floodman:


Wow, when was this? We got some srpinkles he in SA overnight
Good morning Flood...I just noticed it myself. N.E.Texas may get some more..This little guy could effect Cuba..
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1805. Matt74
Quoting Jax82:
MMMmmmmm Toasty.

Thats a recipe for trouble if anything gets in there!
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Quoting Floodman:


Wow, when was this? We got some srpinkles he in SA overnight

Nothing in Austin yet. Patiently waiting for another Hermine.
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1802. Jax82
MMMmmmmm Toasty.

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1801. nigel20
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1800. MTWX
Quoting hydrus:
Some rain for Texas..

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

Link
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1799. hydrus
Quoting sarahjola:
thanks for the lesson:) do you know what the current set up is for high pressure? is it not the high pressure steerring these systems? do you know where i can get a steering current map or outlook? tia
Tracking high pressure in the Atlantic the past 45 days has been very complex, in fact nerve wracking. This area could get interesting soon...The squashed potato look the AB high has had lately as opposed to our close to oval feature..48 hours out
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Quoting hydrus:
Some rain for Texas..


Wow, when was this? We got some srpinkles he in SA overnight
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XXL MOVEMENT
92L WNW
93L W
94L WSW
95L NE
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1794. NEwxguy
Ahhh,now we getting into some real forcasting.

I'll see your pumped ridge and raise you two deep troughs.
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Quoting KEEPEROFTHEGATE:
i raise you 2 herbert boxes and a john hope rule to your 1 herbert box and tunnels


I'm very tempted to raise you heightened sunspot activity and Project StormFury...what the hell! In for a penny, in for a pound...called and raised
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1792. usa777
Quoting KEEPEROFTHEGATE:
the stairs don't go all the way to the landing with this one

Lmao
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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

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.
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Quoting Floodman:


Hows things, tig? MUAH back atya!


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...
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Quoting 12george1:
If all four of these were to develop, and then Jose forms shortly after, we would be ahead of 2005!


And if pigs had wings we'd all of us carry an umbrella
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1787. MTWX
Quoting SQUAWK:

SR-71 shock wave

If only we still used them.. ;)
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1786. nigel20
Quoting hydrus:
Some rain for Texas..

That's really nice to know.
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What would have to happen for 94 to threaten the SE? Based on the models I was thinking it would quickly recurve around the high pressure out to sea... if it even becomes anything more than a few clouds with a slight spin
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1784. nigel20
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Quoting tiggeriffic:


FLOOD!!!!! MUAH BABY!


Hows things, tig? MUAH back atya!
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Quoting KEEPEROFTHEGATE:
the stairs don't go all the way to the landing with this one


ROFL +100!
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1781. hydrus
Some rain for Texas..
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1780. KEEPEROFTHEGATE (Mod)
Quoting usa777:


Huh?
the stairs don't go all the way to the landing with this one
Member Since: July 15, 2006 Posts: 174 Comments: 54434
1778. divdog
Quoting gatorman98:


I dont think many people are listening anyway. Seems they have forgotten 2004 already. None of this is getting a blip in CentFLA.
Storms are too far away and undeveloped for any stations in cfla or for that matter anywhere in the U.S.A to become concerned at this point. Being prepared is what alleviates alot of the worries that hurricanes can cause whether they come close to you or not. Just be prepared, you will have plenty of time to make a plan if a storm approaches.
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Quoting KEEPEROFTHEGATE:
i raise you 2 herbert boxes and a john hope rule to your 1 herbert box and tunnels


I have a full house, naked swirl over pumping the ridge.
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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
heck... I'll see your TUNNELS and raise you a Pumped Ridge!
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1775. usa777
Quoting HOTWHEELS99:
this reminds me exactly of last year and hopefully nothing will hit the east coast and from what the weather channels are saying here it might just be that thank god just alot of problems this year for the shipping lanes


Huh?
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Quoting tiggeriffic:


what is haarp?


"HAARP is a scientific endeavor aimed at studying the properties and behavior of the ionosphere, with particular emphasis on being able to understand and use it to enhance communications and surveillance systems for both civilian and defense purposes.

The HAARP program is committed to developing a world class ionospheric research facility consisting of:

* The Ionospheric Research Instrument (IRI), a high power transmitter facility operating in the High Frequency (HF) range. The IRI will be used to temporarily excite a limited area of the ionosphere for scientific study.
* A sophisticated suite of scientific (or diagnostic) instruments that will be used to observe the physical processes that occur in the excited region.

Observation of the processes resulting from the use of the IRI in a controlled manner will allow scientists to better understand processes that occur continuously under the natural stimulation of the sun."

That's the official word on the program...unofficially it is claimed by a number of individuals that HAARP is altrenatly a weather control technology, a communications device for speaking with , hell, I don't know a or even, heaven help us, a device for causing earthquakes...
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1773. nigel20
Quoting HOTWHEELS99:
92 = recurve and fizzle
93 = recurve
94 = fizzle
95 = runnin g in circles in the middle of nowhere

I don't think that 93L will recurve.
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1771. KEEPEROFTHEGATE (Mod)
Quoting HOTWHEELS99:
its the invest train to nowhere
only one going nowhere is you
Member Since: July 15, 2006 Posts: 174 Comments: 54434
1770. Buhdog
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


i raise one pumping the ridge
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Quoting weathermanwannabe:
Here is a "pretty" model link for latest GFS run on all of our AOI's; click on top to animate.

Link


yes, veeeery "pretty"!
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Quoting Neapolitan:

It's just a downlink/processing error from one of the satellite passes. (Note that the error is wider near the top of the image; that's due to the distortions inherent in the Mercator projection used, which causes increasing distortion as one moves away from the Equator.)

Agreed, after dashing for some emergency coffee and looking again, you can clearly see the artifact.
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Miami NWS not so bullish anymore with the trough next week.

000
FXUS62 KMFL 121233
AFDMFL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
303 AM EDT FRI AUG 12 2011

THEN
INDICATE A SURGE OF DRIER AIR SPREADING WEST OVER SOUTH FLORIDA
MONDAY THROUGH WEDNESDAY OF NEXT WEEK AND A WEAKENING FRONTAL
BOUNDARY DIPPING SOUTH OVER THE SERN REGION...REMAINING NORTH OF
OUR AREA. IF THIS VERIFIES...BELOW AVERAGE RAINFALL CHANCES AND
HIGHER AFTERNOON TEMPERATURES WILL BE MOST LIKELY THROUGH THIS
PERIOD NEXT WEEK.
Member Since: August 19, 2005 Posts: 5 Comments: 5450
1747. IKE

I see you got patented
Member Since: September 23, 2005 Posts: 14 Comments: 11215
1764. SQUAWK
Quoting JNCali:


The sound my grampa used to make right before mom would hurriedly open the closest window... memories...


ROTFLMAO


and I got the visual
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Quoting HOTWHEELS99:
all the weather stations here out of florida are all saying that 92 and 93 will most likely recurve out to sea if they even develop and 2 big fronts that will push down off the east coast next week should also help tear them apart next week and recurve them that was on channel 3 5 and 9 and channel 13 at 945am


I dont think many people are listening anyway. Seems they have forgotten 2004 already. None of this is getting a blip in CentFLA.
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1762. Hugo7
95 prolly gonna get upgraded soon to td, 94(Emily) looks like it has a good chance, but will take a few more days or peter away because of lack of moisture. 93 looks good if it could get it's act together, and 92 is a front runner for hurricane, cat 1-2.
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1761. KEEPEROFTHEGATE (Mod)
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
i raise you 2 herbert boxes and a john hope rule to your 1 herbert box and tunnels
Member Since: July 15, 2006 Posts: 174 Comments: 54434
Quoting IKE:

Joe Bastardi
At least it deals with the
weather. BTW I think Dr Jeff Masters is genuine in his ideas, even
though I disagree with him on AGW

Yea, I saw that last evening. JB's been on a tear the past few days--an unscientific tear, but a tear nonetheless... ;-)
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Quoting hydrus:
The weaker it is while crossing the Atlantic, the further west it will track. There are a lot of different scenarios for 93L. If it does actually enter the Caribbean, this system will be nothing short of dangerous. If for some reason it ends up north of the Leeward Islands, I believe it has a decent chance of recurvature..It is worth mentioning that if the track is just north or south of the Greater Antilles, it most likely will effect Florida and possibly the eastern gulf..jmo
thanks for the lesson:) do you know what the current set up is for high pressure? is it not the high pressure steerring these systems? do you know where i can get a steering current map or outlook? tia
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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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