African tropical wave 99L slowly organizing

By: Dr. Jeff Masters , 1:26 PM GMT on July 31, 2012

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A tropical wave (Invest 99L) near 9°N 41°W, halfway between the Lesser Antilles Islands and the coast of Africa, has the potential to develop into a tropical depression later this week as it moves westward at 10 - 15 mph. Visible satellite loops show that the disturbance now has a moderate amount of poorly-organized heavy thunderstorms that continue to slowly increase in intensity and areal coverage. There is no surface circulation, but some counter-clockwise rotation of the large-scale cloud pattern is evident. Water vapor satellite loops show that 99L has a reasonably moist environment. The latest Saharan air layer analysis shows that the dry air from the Sahara lies to the north of 99L and is currently not affecting the storm. 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 through Friday, and ocean temperatures will remain near 28°C, according to the 8 am EDT run of the SHIPS model. However, a band of high wind shear of 20 - 40 knots associated with the subtropical jet stream lies just to the north of 99L, and it would not be a surprise to see 99L experience some higher shear conditions than are currently forecast. The farther north 99L gets, the higher the shear it will experience, and the SHIPS model is predicting shear in the moderate range, 10 - 20 knots, for Saturday - Sunday, as the storm works its way to 15°N. 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. There are some major differences in the predicted forward speed of 99L, with the ECMWF and UKMET models predicting the storm will reach the Lesser Antilles on Friday, and the GFS predicting a later arrival, on Saturday. At 8 am Tuesday, NHC gave 99L a 20% chance of developing into a tropical depression by Thursday morning. I expect the storm will begin having trouble with tendrils of dry air reaching down from the north at times this week, but 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 morning. The long-range fate of 99L next week is uncertain. A track west to west-northwest through the Caribbean, or to the northwest towards the U.S. East Coast are both possible. The storm is less likely to survive if it heads northwest towards the U.S.

Extreme heat in the Central U.S.
The withering heat in America's heartland continued on Monday, with high temperatures of 112° recorded in Winfield, Kansas and Searcy, Arkansas. Little Rock, Arkansas hit 111°, their 3rd hottest temperature ever record, behind the all time record of 114° set just last year on August 3, and the 112° reading of 7/31/1986. Wichita and Coffeyville in Kansas both hit 111° Monday, and in Oklahoma, Enid, Tulsa Jones Airport, and Chandler all topped out at 111°. Carr Creek, Missouri hit 110°, the hottest temperature measured in the state so far this year. Highs temperatures Tuesday and Wednesday in this region could reach 110° again, as the most extreme heat this week will stay focused over Oklahoma and surrounding states.

Jeff Masters

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for those posting Olympics results.. please understand that a great deal of people would like to watch tonight.. so quit posting the outcome.
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In my opinion the tropical wave by Espanola should be monitored,don't see a lot of shear,people are not paying attention to this feature,they are concentrated more on the other wave in the middle of the Atlantic and we have this one very close to home,I remember Andrew in 1992 was just a tropical wave a little bit East and North of this wave and become a monster,not trying to make any comparison but in my humble opinion this wave should be watch carefully,any thoughts about this??,thank you.
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Member Since: July 17, 2009 Posts: 71 Comments: 25990
Quoting LargoFl:
just wanted to mention what i heard today on the lush limbaugh show...he said.one tenth of ALL humanity..is without electricity today in india,650 million..now regardless of him....how much of India's population in total..hmmm how do i put this...the population of India..is how much of the total of humanity anyway?..geez..one half?


7,029,823,585 vs 650,000,000 10.8%
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Invest 99L is looking better and better by the hour.
Member Since: August 31, 2009 Posts: 0 Comments: 5628
Both 12Z runs of GFS and EURO are pretty close in terms of track and intensity (or lack of it..). When these two models agree this well then for the moment their prediction is a SAFE bet!
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We could be looking at a very very nasty setup for the month of August. The SE and GOM could be in some serious trouble. I am going to be looking very closely at the GFS and it's movement of that massive Bermuda high over the coming weeks. It will be a crucial over the coming weeks.
Member Since: May 22, 2010 Posts: 0 Comments: 907
120 hours
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Quoting robert88:
If king TUTT doesn't lift out by the time 99L gets into the Caribbean...it's lights out. I don't get why some people can't see that. The wave that just came off Africa the other day will be the one to watch. It's further N and the Bermuda high is setting up shop right now off the EC. The pattern did a 360.

Ain't gonna affect it. Look at your shear forecast maps.
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We're on track with the 2011 Atlantic hurricane season thus far. Tropical Storm Emily formed on August 1, and it appears that Tropical Depression Five will develop either tomorrow or August 2.
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Quoting LargoFl:
.gender doesnt matter in weather unless your talking about Mother Nature lol


Not sure about that, Maria Molina works for me!
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12Z EURO @ 120hrs
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657. VR46L
2 crayon circles now but....
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boy south carolina once again now today..surely they cannot be in drought anymore huh..............................BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
216 PM EDT TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN GREENVILLE-SPARTANBURG HAS ISSUED A

* FLASH FLOOD WARNING FOR...
CENTRAL GREENVILLE COUNTY IN UPSTATE SOUTH CAROLINA...

* UNTIL 800 PM EDT

* AT 212 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED AN
AREA OF VERY HEAVY RAINFALL ACROSS THE WARNED AREA. DOPPLER RADAR
ESTIMATED RAINFALL AMOUNTS FROM 1 TO 2 INCHES AN HOUR WERE
OCCURRING ACROSS THE AREA.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
DOWNTOWN GREENVILLE...CHERRYDALE POINT...FURMAN UNIVERSITY...
GREER...HAYWOOD MALL...MAULDIN...PELHAM ROAD AT I-85...SHOPS AT
GREENRIDGE...TAYLORS...TRAVELERS REST AND WHITE HORSE ROAD AT I-85.

REEDY RIVER IS CURRENTLY NEAR FLOOD STAGE AND EXPECTED TO RISE ABOVE
FLOOD STAGE IN THE NEXT FEW HOURS. LOCAL CREEKS SUCH AS GILDER AND
BRUSHY CREEKS WILL LIKELY GO OVER BANKFULL AND FLOOD LOW LYING AREAS
AND ROADWAYS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...
COUNTRY ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND
OTHER LOW LYING AREAS ARE SUBJECT TO FLOODING.

TO REPORT HIGH WATER...FLOODING...MUDSLIDES...LANDSLIDES OR OTHER
SEVERE WEATHER THROUGH OUR AUTOMATED REPORTING SYSTEM...CALL OUR TOLL
FREE NUMBER... 1 8 7 7...6 3 3...6 7 7 2.



LAT...LON 3477 8245 3482 8248 3483 8248 3484 8249
3488 8249 3492 8252 3497 8253 3501 8222
3476 8222 3476 8246



JOH
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Quoting TropicalAnalystwx13:

We'll see at 2:49 pm EDT and 3:51 pm EDT. That's when he competes in the 200 meter butterfly final and 800 meter freestyle relay, respectively.

Well I would like to watch it tonight so please do not discuss the outcome on here. Thanks
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Quoting Hoff511:


Does anyone think Ernesto will be an analog storm for Ernesto?
http://en.wikipedia.org/wiki/File:Ernesto_2006_tr ack.png


Very possible. There will be a trough present on the east coast. If not strong enough to fully turn it N on an Ernesto path, it will head WNW and into the GOM eventually.
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Quoting MontanaZephyr:


It would be interesting to see a good demographic study about meteorologists, TV meteorologists, people that are interested enough in weather to follow this blog, first year met students, etc.

Just my hunch but even after factoring out cultural bias in favor of white males, white males will still make up the vast portion of all groups mentioned above. More, at least half are gay (I don't mean that in a derogatory way ... if I were to dis anything that way, it would be the tastes of the breeding classes). I don't think I've ever met a straight TV weatherman. ... not in the last thirty years at least.

Carl Parker? Jeff Morrow? My local meteorologists?
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Quoting Patrap:
Humans listen to RUSH?

LoL
no but LUSH they do
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Humans listen to RUSH?

LoL
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Quoting robert88:
If king TUTT doesn't lift out by the time 99L gets into the Caribbean...it's lights out. I don't get why some people can't see that. The wave that just came off Africa the other day will be the one to watch. It's further N and the Bermuda high is setting up shop right now off the EC. The pattern did a 360.


You mean this. Yep, posted it a few times today. It could have a very strong influence on the system.

Member Since: July 17, 2009 Posts: 71 Comments: 25990
Quoting CarolinaHurricanes87:


Please do not believe everything (or really anything) you hear on that show... at least not before verifying yourself.

You have no idea what he is talking about because he's talking out of his... you know.

Trying to use the situation in India for political jargon in this country (that we should use more coal).

Best bet.... don't listen to a word he says, don't give him any ratings. He's a lunatic out to brainwash you.... not to provide real information on anything
yeah i know..i sometimes listen to him in the car, and laugh most of the way, i dont believe a word he says, he surely is not for the working man or woman
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Quoting VR46L:


Happened to me a few times too...Its almost as though , if you have an interest in weather you must be male ...


It would be interesting to see a good demographic study about meteorologists, TV meteorologists, people that are interested enough in weather to follow this blog, first year met students, etc.

Just my hunch but even after factoring out cultural bias in favor of white males, white males will still make up the vast portion of all groups mentioned above. More, at least half are gay (I don't mean that in a derogatory way ... if I were to dis anything that way, it would be the tastes of the breeding classes). I don't think I've ever met a straight TV weatherman. ... not in the last thirty years at least.
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Quoting LargoFl:
.......in his radio show..he said the power failure was because india stopped using COAL to generate electricity...i have NO idea what he is thinking because last i heard it was a monsoon that hit the power plants..again I..could be wrong also


Please do not believe everything (or really anything) you hear on that show... at least not before verifying yourself.

You have no idea what he is talking about because he's talking out of his... you know.

Trying to use the situation in India for political jargon in this country (that we should use more coal).

Best bet.... don't listen to a word he says, don't give him any ratings. He's a lunatic out to brainwash you.... not to provide real information on anything
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Quoting stormchaser19:
99L is reaching waters of 29 degrees, not surprising me if continues grow in size


Good observation. Check the conditions to the NW.
Member Since: July 17, 2009 Posts: 71 Comments: 25990
If king TUTT doesn't lift out by the time 99L gets into the Caribbean...it's lights out. I don't get why some people can't see that. The wave that just came off Africa the other day will be the one to watch. It's further N and the Bermuda high is setting up shop right now off the EC. The pattern did a 360.
Member Since: May 22, 2010 Posts: 0 Comments: 907
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE COLUMBIA SC
207 PM EDT TUE JUL 31 2012

THE NATIONAL WEATHER SERVICE IN COLUMBIA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
NORTHWESTERN BAMBERG COUNTY IN CENTRAL SOUTH CAROLINA
EASTERN AIKEN COUNTY IN CENTRAL SOUTH CAROLINA
WESTERN ORANGEBURG COUNTY IN CENTRAL SOUTH CAROLINA
NORTHEASTERN BARNWELL COUNTY IN CENTRAL SOUTH CAROLINA

* UNTIL 300 PM EDT

* AT 205 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
OF 60 MPH. THIS STORM WAS LOCATED NEAR BLACKVILLE...OR 8 MILES
NORTHWEST OF DENMARK...AND MOVING EAST AT 10 MPH.

* SOME COMMUNITIES IN THE WARNING AREA INCLUDE WILLISTON...
ORANGEBURG...DENMARK...BLACKVILLE AND BAMBERG

REPORT LARGE HAIL...DAMAGING WINDS OR FLOODING TO YOUR COUNTY
SHERIFF...OR CALL THE NATIONAL WEATHER SERVICE...TOLL FREE 1 877 6 3
3...6 7 7 2.

LAT...LON 3368 8147 3351 8085 3338 8091 3327 8102
3344 8171
TIME...MOT...LOC 1807Z 254DEG 7KT 3341 8123
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Quoting TropicalAnalystwx13:

That's even worse...but moving on.

Yes, I see the SOI is falling. Still like to pay attention to the 30-day SOI values instead of daily values, though.


It's a saying meaning playing around. Geesh people get a sense of humor.
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Watch for the next flare-up of convection near the NW quadrant. Upper atmosphere is getting better for convection to build there first. In the next hour, you should begin to see it.

Member Since: July 17, 2009 Posts: 71 Comments: 25990
592. 1928PalmBeach 1:55 PM EDT on July 31, 2012

Welcome to the Blog and an excellent comment and first post. A lot of the discussion on here, which is fun sometimes and can be brutal at times as well, boils down to Man vs. Machine vs. Mother Nature. Man trying to second guess the Models (which NHC forecasts are usually based on); the Machines (Models) trying to tell Man what is going to happen 7-10 days out, and Mother Nature throwing a curve ball at everyone from time-to-time.

This is not an exact science in the long term no matter what Man or Machine says.
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Never seen the "Large Eye" scene type before.



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 31 JUL 2012 Time : 173000 UTC
Lat : 22:22:07 N Lon : 123:41:28 E


CI# /Pressure/ Vmax
4.6 / 956.3mb/ 79.6kt


Final T# Adj T# Raw T#
4.6 4.8 4.9

Estimated radius of max. wind based on IR : 36 km

Center Temp : +12.1C Cloud Region Temp : -57.8C

Scene Type : LARGE EYE

Positioning Method : SPIRAL ANALYSIS

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 1.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 90km
- Environmental MSLP : 993mb

Satellite Viewing Angle : 35.5 degrees
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99L IMO is starting pull a little N of due west and is gradually moving out of the ITCZ.
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12Z Euro is further north this run and weaker.

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Quoting StormTracker2K:





I fixed it right away. Sorry. LOL

Damm! SOI is falling fast. Hey TA13 you see this. You know I like to bust your balls all the time but I always love your input on here.



That's even worse...but moving on.

Yes, I see the SOI is falling. Still like to pay attention to the 30-day SOI values instead of daily values, though.
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Quoting N3EG:


No tech support today.

Maybe they need to outsource their power generating.
.......in his radio show..he said the power failure was because india stopped using COAL to generate electricity...i have NO idea what he is thinking because last i heard it was a monsoon that hit the power plants..again I..could be wrong also
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Quoting LargoFl:
..imagine..having 17% of the worlds population in one country..must be living wall to wall there, after all..its not big like the USA is in area



You are correct.

United states has 31.6 people per square KM (population density)

India has 349.2 people per square KM

Quite the difference... I was surprised to see India has a higher population density than Japan, despite being soooo much larger in size.
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Quoting RitaEvac:


Pack rats, which is why during extreme weather events, masses die

Easy on the choice words Sir..., there are a few Indians on this blog! Yes it's a very populated country
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Here is Saola.

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Quoting MississippiWx:


John Hope. Duh.
............I liked him and believed him on the weather
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99L is reaching waters of 29 degrees, not surprising me if continues grow in size
Member Since: June 20, 2012 Posts: 0 Comments: 2155
628. N3EG
Quoting CarolinaHurricanes87:


Anyway, India has roughly 1.2 billion. That'd put them at about 17% of the global population. Meaning that his # is pretty close... between 9-10% of the worlds population was/is involved in the India power outage today.


No tech support today.

Maybe they need to outsource their power generating.
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Quoting MississippiWx:


John Hope. Duh.

Correct :) You get the cookie ;) Still, I thought that was the interesting fact for such a horrible storm.
Member Since: August 1, 2011 Posts: 28 Comments: 7981
Quoting Bluestorm5:
Fun Trivia :)

In 1969, a famous meteorologist added his daughter's name to the name list for that hurricane season as a graduation gift. He had no way of knowing at the time that the hurricane that would take his daughter's name, Camille, would become one of the most powerful and destructive hurricanes to ever hit the United States. Can you name that famous meteorologist?


John Hope. Duh.
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Quoting StormTracker2K:


Damm! SOI is falling fast. Hey TA13 you see this. You like to bust your balls all the time but I always love your input on here.

I like to what?
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Quoting muddertracker:
Well...as far as blogger gender...we have had "pretender trolls" in the past...so it can get a bit tricky :)
.gender doesnt matter in weather unless your talking about Mother Nature lol
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Quoting StormTracker2K:


how did Phelps do today?

We'll see at 2:49 pm EDT and 3:51 pm EDT. That's when he competes in the 200 meter butterfly final and 800 meter freestyle relay, respectively.
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Quoting LargoFl:
..imagine..having 17% of the worlds population in one country..must be living wall to wall there, after all..its not big like the USA is in area


Pack rats, which is why during extreme weather events, masses die
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Quoting StormTracker2K:


Damm! SOI is falling fast. Hey TA13 you see this. You like to bust your balls all the time but I always love your input on here.


He likes to what??
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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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