African tropical wave 99L has potential to develop

By: Dr. Jeff Masters , 3:10 PM GMT on July 30, 2012

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The first African tropical wave of 2012 with a potential to develop is Invest 99L, located in the Eastern Atlantic near 9°N 36°W, midway between the Lesser Antilles Islands and the coast of Africa. Visible satellite loops show a large area of the surrounding atmosphere has a pronounced counter-clockwise spin, though there is no surface circulation. The disturbance's heavy thunderstorm activity is pretty sparse, but appears to be slowly increasing. Water vapor satellite loops show that 99L has a reasonably moist environment, and the latest Saharan air layer analysis shows that the dry air from the Sahara lies well to the north of 99L. WInd shear over the disturbance is a light 5 - 10 knots, and ocean temperatures are 28°C, (82°F) which is well above the 26.5°C (80°F) threshold typically needed to allow formation of a tropical depression.


Figure 1. Morning satellite image of Invest 99L.

Forecast for 99L
Wind shear is expected to remain light for the next five days, and ocean temperatures will remain near 28°C, according to the 8 am EDT run of the SHIPS model. The disturbance is at 9°N, which is close enough to the Equator that the storm will have some difficultly getting spinning. Most of the models are showing some slow development of 99L, with the storm reaching the Lesser Antilles Islands on Saturday, August 3. NHC gave 99L a 20% chance of developing into a tropical depression by Wednesday morning. I expect the storm will have trouble with dry air at times this week as it crosses the Atlantic, but I give 99L a 50% chance of eventually developing into Tropical Storm Ernesto sometime in the next ten days. Residents and visitors to the Lesser Antilles Islands should anticipate heavy rains and strong winds from 99L beginning to affect the islands as early as Friday night. The long-range fate of 99L is uncertain, but a trough of low pressure is expected to be present over the Eastern U.S. early next week, which would be capable of turning 99L more to the northwest.

Hot in the Central U.S.
The heat in America's heartland continued on Sunday, with Wichita, KS hitting 111°F, just 3° short of their all-time hottest temperature of 114° set on 8/12/1936. Other notable highs on Sunday:

111° Coffeyville, KS
111° Winfield, KS
110° Chanute, KS
110° Parsons, KS
109° Joplin, MO (all-time record is 115° on July 14, 1954)

The low temperature in Tulsa, Oklahoma this Monday morning dropped to only 88°F. This is the all-time warmest low temperature in the city since record keeping began in 1905. The previous record warmest minimum temperature was 87°F set on August 2, 2011 and July 16, 1980. The high in Tulsa Monday - Wednesday is expected to reach 110° - 111°, close to the city's all-time hottest temperature of 115° set on August 10, 1936.

Jeff Masters

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1120. JLPR2
Quoting Tazmanian:



nop its at 9.0N

30/1745 UTC 9.0N 37.1W TOO WEAK 99L


Don't trust satellite estimates on storm positions. xD

AL, 99, 2012073018, , BEST, 0, 87N, 358W, 20, 1010, DB
Member Since: September 4, 2007 Posts: 7 Comments: 8732
Quoting BahaHurican:
I'm glad I saw ur post before u disappeared... I've been meaning to compliment you on the timely imagery for a while.

I hope your "project" goes successfully, and look forward to talking wx with you in the future.



Thanks.
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Quoting Grothar:


Hey, Geoff, any chance this could make it to the Cayman Islands?


Depends who you ask :). Right now, I will say no.
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Quoting Civicane49:


Thank you very much.

However, I will still be here until late in this evening. After that, I will be gone for a while.

I will miss you. visit back often. I respect all waht you do here, your on my respected bloggers list.
Member Since: Posts: Comments:
Quoting SFLWeatherman:
Q. What day will we get a TD or TS
A. Tomorrow TD
B. Tomorrow TS
C. Wednesday TD
D. Wednesday TS

C or Thursday.
Member Since: July 6, 2010 Posts: 113 Comments: 32247
Quoting Civicane49:


Thank you very much.

However, I will still be here until late in this evening. After that, I will be gone for a while.
I'm glad I saw ur post before u disappeared... I've been meaning to compliment you on the timely imagery for a while.

I hope your "project" goes successfully, and look forward to talking wx with you in the future.

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1113. JLPR2
Quoting TropicalAnalystwx13:

Shred to pieces by what? The shear that doesn't exist? XD


Take a close look above 10N at 35-40W and onward.



CATL above 10N int exactly favorable, it needs to ride low to have a chance.
Member Since: September 4, 2007 Posts: 7 Comments: 8732
This is nasty!!!
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Quoting SFLWeatherman:
Q. What day will we get a TD or TS
A. Tomorrow TD
B. Tomorrow TS
C. Wednesday TD
D. Wednesday TS

C.
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1109. ncstorm
Quoting LargoFl:
..NC in what timeframe?




august 7
Member Since: August 19, 2006 Posts: 13 Comments: 15643
Quoting Articuno:

I think "Ernesto" will be positioned exactly where the tropical wave in front of it is, by the weekend.
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Quoting SFLWeatherman:
Q. What day will we get a TD or TS
A. Tomorrow TD
B. Tomorrow TS
C. Wednesday TD
D. Wednesday TS

E. Thursday TD
Member Since: Posts: Comments:
Quoting SFLWeatherman:
Q. What day will we get a TD or TS
A. Tomorrow TD
B. Tomorrow TS
C. Wednesday TD
D. Wednesday TS

A
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Quoting HurricaneDean07:

Seems to slowly be organizing...
It should be 30% by tomorrow morning.
99L is currently positioned at 8.7 N, and is moving due west, with a slight northerly component.



nop its at 9.0N

30/1745 UTC 9.0N 37.1W TOO WEAK 99L
Member Since: May 21, 2006 Posts: 5091 Comments: 115247
Q. What day will we get a TD or TS
A. Tomorrow TD
B. Tomorrow TS
C. Wednesday TD
D. Wednesday TS
Member Since: May 23, 2012 Posts: 0 Comments: 4664
Quoting Grothar:


I don't expect depression status until Tuesday or even early Wednesday.

Grothar... Tomorrow's Tuesday.
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Quoting BahaHurican:
You will be missed. I have appreciated your imagery posts in particular, but thanks for bringing your ideas to the blog...


Thank you very much.

However, I will still be here until late in this evening. After that, I will be gone for a while.
Member Since: Posts: Comments:
Quoting SFLWeatherman:

Seems to slowly be organizing...
It should be 30% by tomorrow morning.
99L is currently positioned at 8.7 N, and is moving due west, with a slight northerly component.
Member Since: Posts: Comments:
Quoting Grothar:


I don't expect depression status until Tuesday or even early Wednesday.

Tuesday's tomorrow Gro... You think it could develop that fast?
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1098. etxwx
Millions left powerless as Tropical Storm Saola lashes across Philippines
Agence France-Presse Jul 31, 2012
Excerpt: MANILA // At least three people were killed and millions were left without power Monday as Tropical Storm Saola turned into a typhoon, bringing heavy rains to large parts of the Philippines, the government said. Manila was one of the worst hit areas and schools across the sprawling capital were suspended, largely due to flooding, the National Disaster Risk Reduction and Management Council said. Nearly 13,000 people were evacuated in Manila, other parts of the main island of Luzon and the central Visayas region, as rainfall reached 20 millimetres an hour, according to the council.
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Quoting Civicane49:
Repost for those who missed my blog entry earlier today.



I wanted to tell everyone that I won’t be here in WU for a while starting tomorrow. I will also not be posting new entries for a long time, but I will release my last very special entry of the year on September 11. I have a lot of work to do starting on the beginning of August. I would like to thank you all for letting me enjoy this site and visiting my blog updates. It truly feels like a community here. However, I will come back on September 11 very briefly to let you guys know that I released a special entry. I will also come back from time to time, if time permits. I’ll miss this place.
You will be missed. I have appreciated your imagery posts in particular, but thanks for bringing your ideas to the blog...
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1096. Grothar
Quoting GeoffreyWPB:
Tropical Cyclone Report
Hurricane Ivan
2-24 September 2004


Hey, Geoff, any chance this could make it to the Cayman Islands?
Member Since: July 17, 2009 Posts: 71 Comments: 26410
Quoting TropicalAnalystwx13:

Shred to pieces by what? The shear that doesn't exist? XD
Salt exist...
Quoting JLPR2:


Hey come on! XD

Too early in the year, I don't want a storm yet, I'm not prepared mentally to deal with that.
9 lat, and 37 L, this time of the year ,historically a close call for Puerto Rico, remembering Betsy , (santa Clara, on August 13,1956...
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Quoting Articuno:
Interesting that Ivan actually intensified in the dead zone in the caribbean.Felix did the same thing If memory serves correctly.
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1092. Grothar
Quoting Tropicsweatherpr:


But NHC remained at 20%. I think they are waiting to see it detached from ITCZ and then go upwards in the %from the moment that happens.


I don't expect depression status until Tuesday or even early Wednesday.
Member Since: July 17, 2009 Posts: 71 Comments: 26410
That's great, it starts with an earthquake, birds and snakes, an aeroplane
And Lenny Bruce is not afraid
Eye of a hurricane, listen to yourself churn
World serves its own needs, dummy serve your own needs.
Feed it off an aux speak, grunt
No strength the ladder starts to clatter with the fear, fight down height.
Wire in a fire, representing seven games with a government for hire and a combat site.
Left of West and coming in a hurry with the furies breathing down your neck.
Team by team reporters baffled, trump, tethered crop.
Look at that low playing! Fine then.
Uh oh, overflow, population, common food, but it'll do.
Save yourself, serve yourself.
World serves its own needs, listen to your heart bleed.
Dummy with the rapture and the reverent in the right - right.
You vitriolic, patriotic, slam, fight, bright light,
Feeling pretty psyched.

It's the end of the world as we know it.
It's the end of the world as we know it.
It's the end of the world as we know it and I feel fine.

Six o'clock - TV hour.
Don't get caught in foreign towers.
Slash and burn, return, listen to yourself churn.
Locking in uniforming, book burning, blood letting.
Every motive escalate. Automotive incinerate.
Light a candle, light a votive.
Step down, step down.
Watch your heel crush, crush. Uh oh,
This means no fear - cavalier.
Renegade, steer clear!
A tournament, a tournament, a tournament of lies.
Offer me solutions, offer me alternatives
And I decline.

It's the end of the world as we know it.
It's the end of the world as we know it.
It's the end of the world as we know it and I feel fine.

The other night I dreamt of knives, continental drift divide.
Mountains sit in a line
Leonard Bernstein.
Leonid Breshnev, Lester Bangs and Lenny Bruce.
Birthday party, cheesecake, jelly bean, boom!
You symbiotic, patriotic, slam book neck, right?
Right.

It's the end of the world as we know it.
It's the end of the world as we know it.
It's the end of the world as we know it and I feel fine... fine...

(It's time I had some time alone,
It's time I had some time alone,
It's time I had some time alone
I feel fine...)

For All The Doomers!!.......lol
Member Since: Posts: Comments:
Quoting StormJunkie:
Very electrical storm about to hit Buzzards roost marina. Live Feed.

And presslord is here with me.
Why do I always feel that press + SJ = shenanigans?

LOL

U streaming again, I see... but can't watch tonight 'cause I got an early call tomorrow...

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Member Since: May 23, 2012 Posts: 0 Comments: 4664
1088. JLPR2
Quoting sunlinepr:
Where is the wind, lighting and the rain???




Seems not much for us.
Member Since: September 4, 2007 Posts: 7 Comments: 8732
1087. JLPR2
Quoting Tropicsweatherpr:
JLPR2, the PR split occurd with wave. I was expecting plenty of rain but so far nothing important in terms of rainfall. Let's see if the tail brings some.


Eh?

Yeah, not much rain, the airport is currently reporting a grand total of 0.13inches for today.
Member Since: September 4, 2007 Posts: 7 Comments: 8732
1086. Patrap


Member Since: July 3, 2005 Posts: 426 Comments: 128617
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1084. Gearsts
Quoting sunlinepr:
Where is the wind, lighting and the rain???


lol im asking the same thing!
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JLPR2, the PR split occurd with wave. I was expecting plenty of rain but so far nothing important in terms of rainfall. Let's see if the tail brings some.
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Repost for those who missed my blog entry earlier today.

Quoting Civicane49:
Blog update:

Tropical wave 99L has a chance to develop in the Atlantic

Please check it out.


I wanted to tell everyone that I won’t be here in WU for a while starting tomorrow. I will also not be posting new entries for a long time, but I will release my last very special entry of the year on September 11. I have a lot of work to do starting on the beginning of August. I would like to thank you all for letting me enjoy this site and visiting my blog updates. It truly feels like a community here. However, I will come back on September 11 very briefly to let you guys know that I released a special entry. I will also come back from time to time, if time permits. I’ll miss this place.
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Quoting washingtonian115:
99L is popping for us tonight..now only if it could gain some latitude or else this baby is going into S.A.

If current trends continue... The system will slowly strengthen, and as it does so, it will lift further northward, above 10N.
This is what's going to get 99L going... and should allow it to intensify into a Storm.
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levi is the first wave dying?
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1078. LargoFl
well this is it for me,we had a great day posting huh!!!..have a safe night everyone...................................
Member Since: August 6, 2011 Posts: 4 Comments: 39025
1077. Patrap
Charleston
NEXRAD Radar
Type
Base Reflectivity 0.50° Elevation
Range 124 NMI

Member Since: July 3, 2005 Posts: 426 Comments: 128617
1076. maeko
Hey, is it just me (which is highly likely 'cause I'm no weather expert) or does the storm activity around the SC coast starting to look a little 'tropical'? Just curious...
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1075. Grothar
Quoting icmoore:


:) My husband will say well "storm cloud", where he got this I don't know he reads too many books and watches too many old movies, what is the weather going to do at which point I defer to you guys and say I know nothing and I say nothing....but they do thank goodness :)


I guess we all get a little ribbing. Hey, we could be doing worse things.
Member Since: July 17, 2009 Posts: 71 Comments: 26410
Quoting Patrap:

It's swinging on a vine. XD
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Quoting LargoFl:
..if it runs north it runs into that huge dust cloud
And then it'll help aid development in the east pacific.
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Where is the wind, lighting and the rain???


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1071. JLPR2
If I remember correctly wasn't Ivan in the ITCZ when it formed? It was at 9.7N after all.
Member Since: September 4, 2007 Posts: 7 Comments: 8732
1070. LargoFl
Quoting washingtonian115:
99L is popping for us tonight..now only if it could gain some latitude or else this baby is going into S.A.
..if it runs north it runs into that huge dust cloud
Member Since: August 6, 2011 Posts: 4 Comments: 39025

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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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