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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Quoting Tropicsweatherpr:


That is good. Let's see if other islands like Antigua,Guadeloupe,St Kitts,Nevis,Dominica got the same.


Got some rain here in Antigua. Not as much as I had anticipated but thankful anyway
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Member Since: August 6, 2011 Posts: 4 Comments: 40778
002

NOUS42 KNHC 302030

WEATHER RECONNAISSANCE FLIGHTS

CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.

0845 AM EDT MON JULY 30 2012

SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)

VALID 31/1100Z JULY TO 01/1100Z AUGUST 2012

TCPOD NUMBER.....12-073



I. ATLANTIC REQUIREMENTS

1. NEGATIVE RECONNAISSANCE REQUIREMENTS.

2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.



II. PACIFIC REQUIREMENTS

1. NEGATIVE RECONNAISSANCE REQUIREMENTS.

2. SUCCEEDING DAY OUTLOOK.....NEGATIVE.

JWP


Member Since: July 15, 2006 Posts: 175 Comments: 54827
Quoting GTcooliebai:
Sorry didn't know what you meant by not seeing it:

Yesterday:



Today:


For the record the CMC was probably too far north yesterday to begin with.
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They're having a live weather chat on ABC action news.com with Denis discussing the upcoming entity.
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..in the bottom right hand part of the match,you can see just the beginning of the wave coming into view..
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Quoting wunderkidcayman:
Guys I have a feeling that the trades won't be so much of a problem for 99L and I think 99L will be a carib tracker and I think it will evenutaly ride up the US E coast

Trade winds are strong, there is no debating that. Just look at visible satellite loops. They're not just going to let up for no reason overnight.
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Quoting LargoFl:
..in the bottom right hand part of the match,you can see just the beginning of the wave coming into view..
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A year after floods, shippers face low Miss. River

Updated: Jul 30, 2012 9:26 AM CDT



MEMPHIS, Tenn. (AP) - A year after the Mississippi River swelled to near-historic proportions and flooded farms and homes from Illinois to Louisiana, the level along the waterway's southern half is so low that cargo barges have run aground and their operators have been forced to lighten their loads.

Wide, sandy strips of shoreline usually invisible even in the low season are now exposed, shrinking the river's width and affecting the way tow captains navigate.

Such is life along the nation's main inland waterway, where millions of tons of goods are shipped every year, some of which end up as exports departing from south Louisiana ports. Those who make their living along the Mississippi learn to adapt to the river's fickle nature.

"It's remarkable, but it's completely normal," said Jim Pogue, spokesman for the Army Corps of Engineers in Memphis. "You get a low river, you get a high river, but it's completely normal."

There isn't much man can do to deal with the exceptionally low river, which at Memphis, is just about 6 feet above the record low.

"Pray for rain," said Tommy Hart, director of the port in Greenville, Miss. "I'm not a big fan of rain, but this time I am."

Aside from that, the best coping mechanism is careful navigation. With the river this low, the channels are shallower and narrower, presenting problems for barges loaded with coal, grain, iron, steel, sand, gravel and more. They must reduce their loads to avoid bottoming out and take extra care not to collide when passing another string of barges in the thinner channel.

Also, low water at docks and terminals makes it more difficult to load or unload material, as ships have trouble getting close enough to docks. Companies must get permits from the Army Corps to dredge near their docks to find deeper places to load and unload.

The National Weather Service said the Mississippi River gauge in Memphis was at minus-4.8 feet on Friday, but there's no need to panic. The "minus" reading does not mean the river is dried up - it's just a measurement based on how the river gauge is designed. Essentially, the reading means the river level is far below normal.

That low level stands in contrast to the flood of 2011, which saw the Mississippi fall about a foot short of the record crest of 48.7 feet set in 1937. The National Weather Service has set the official crest of last year's flood at 48.03 feet on the Memphis gauge.

"It's basically just the opposite of last year," Pogue said.

One reason for the difference is a lack of rainfall in the Ohio River valley and the north Mississippi River basin, said Ryan Husted, a National Weather Service meteorologist in Memphis. Sections of Tennessee and regions to the north are experiencing drought conditions. Most areas in the Mid-South are 10 inches or more below normal for rainfall for the year, the weather service said.

Lower-than-normal snowfall levels over the northern plains this winter are also an issue, Husted said. Less snow means less water from melted snow making its way into the Mississippi and the rivers that feed it.

The record low on the Memphis gauge is minus-10.7, set during a severe drought in 1988. That year, a stretch of river about 100 miles south of Memphis was temporarily closed, Pogue said.

Near Greenville, Miss., more than 700 barges were backed up on the river. Crews dredged day and night to make the river deep enough for traffic to resume.

A paper published in the Bulletin of the American Meteorological Society in September 1989 estimated that the drought caused the U.S. barge industry to suffer a 20 percent income loss, with total losses at about $1 billion that year.

The Army Corps predicts that the river will drop to within about 2 feet of the record, but it is not expected to reach it, Pogue said. So far, no stretch of the river has been closed, but at least one harbor, in Hickman, Ky., has been shut down.

Since 1988, the Corps has worked to improve the navigation system in the river, making sure channels are sufficiently deep. That means the river wouldn't necessarily close, even if the record low is reached this year, Pogue said.

Although Coast Guard officials say closings are not imminent, there have been problems. Towed barge groundings are up compared with years when the river's water level was normal, said agency spokesman Ryan Gomez said.

Meanwhile, barge operators have to carry less cargo to avoid running aground, which means they make less money each trip.

Nashville-based Ingram Barge Company, which operates on the Mississippi and other rivers, has seen business suffer, said Ingram spokesman Keel Hunt.

"Captains and crews know how to navigate through waters high or low," Hunt said. "In a time like this, however, it's a particular challenge because in some cases it's just very difficult to move a barge full of products."

In Arkansas, the water is so low where the White River meets the Mississippi that barges must pass through a series of river locks. And in New Orleans, the Mississippi is so low that the wooden pilings of the wharfs near the French Quarter have been exposed.

But shippers and river pilots reported no navigation problems. Michael Lorino, the head of a pilots group that takes ships across the pass at the mouth of the Mississippi, said recent dredging by the Army Corps had made it a smooth ride for ocean-going vessels.

Anthony Hauer, director of the port at Natchez, Miss., said his port has a deep water channel, and it's not likely barges would have to lighten their loads there.

At Greenville, port director Hart checks the river's level every day. This is harvest season, a busy time for a port that ships goods from the heart of Mississippi's farmlands. According to the Mississippi Department of Intermodal Planning website, the port at Greenville ships potash, rice, corn, wheat, grain feed ingredients, fertilizer and scrap.

A major concern at Greenville and other ports is that the entrance to the river could get too shallow. If that happens, barges could be forced to carry lighter loads to make it to the channel, and the port is hoping to dredge its opening to the river to keep traffic flowing.

"We seem to be living in a day and age of extremes. We had the flood last year and now we have low water," Hart said.



Mohr reported from Jackson, Miss. Associated Press writer Cain Burdeau contributed to this report from New Orleans.

(Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)
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&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

.EQUIPMENT OUTAGES KNOWN AND PLANNED...
EDWARDS AFB WSR-88D...ETR TUESDAY JULY 31
SAN DIEGO/MIRAMAR WSR-88D...PLANNED OUTAGE TUESDAY 0800-1100 PDT.

&&

.SHORT TERM...

REMAINDER THIS EVENING...
RECENT SATELLITE/RADAR IMAGERY LOOPS INDICATE THE LOW TO MID LEVEL
CIRCULATION OVER IMPERIAL COUNTY STARTING TO LIFT NORTHWARD. WILL
STAY WITH FLASH FLOOD WATCH FOR REMAINDER OF EVENING. RAINFALL
REPORTS/RATES SO FAR ARE IMPRESSIVE FOR REGION...BUT ALSO TYPICAL
FOR PULSE TYPE STORMS IN TROPICAL AIR MASS.THE SURFACE OBS ACROSS
INLAND EMPIRE AND THE HRRR MODEL SHOW ELSINORE CONVERGENCE SETTING
UP ABOUT THIS TIME...2 PM AND CONTINUING THROUGH AT LEAST 6 PM.
STRONG LOW LEVEL MOISTURE ADVECTION HAS BEEN TAKING PLACE THROUGH
THE BANNING PASS WITH DEWPOINTS IN THE 70S AND EAST WINDS 15-25 MPH.
EXPANDED THE COVERAGE AREA FOR TSTMS/SHWRS THIS EVENING TO INCLUDE
MOST OF THE RIVERSIDE COUNTY PORTION OF THE INLAND EMPIRE. OTHERWISE
FORECAST MORE OR LESS UNCHANGED SINCE THE LATE MORNING UPDATE.

TONIGHT THROUGH WEDNESDAY...FROM PREVIOUS DISCUSSION
THE PROXIMITY OF THE LOW/MID LEVEL CIRCULATION WHETHER IT DOES SHIFT
BACK OVER SE CALIFORNIA OR REMAINS BUMPED UP AGAINST THE MOUNTAINS
OF SW CALIFORNIA...THE UPPER LEVEL LOW RETROGRADING BACK OVER SE
CALIFORNIA PER GFS AND EARLIER RUNS OF ECMWF MODEL...AND THE
RESIDUAL MONSOON MOISTURE OVER THE AREA...ALL POINT TO A MOIST AND
CONDITIONALLY UNSTABLE ENVIRONMENT CONTINUING OVER THE EASTERN HALF
OF THE FORECAST AREA. MAY NEED TO CONSIDER ADDITIONAL FLASH FLOOD
WATCHES FOR TUESDAY AND PERHAPS WEDNESDAY.
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Member Since: August 6, 2011 Posts: 4 Comments: 40778
Guys I have a feeling that the trades won't be so much of a problem for 99L and I think 99L will be a carib tracker and I think it will evenutaly ride up the US E coast
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Eastern Atlantic
Precipitable Water

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000
ABNT20 KNHC 301743
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT MON JUL 30 2012

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE LOCATED
ABOUT 900 MILES SOUTHWEST OF THE CAPE VERDE ISLANDS CONTINUES TO
PRODUCE DISORGANIZED SHOWER AND THUNDERSTORM ACTIVITY.
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR SOME GRADUAL
DEVELOPMENT OVER THE NEXT FEW DAYS...AND THIS SYSTEM HAS A LOW
CHANCE...20 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS AS IT MOVES WESTWARD AT 10 TO 15 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BRENNAN
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Quoting Articuno:
The blog is bored.

We need something to track:)
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Quoting Grothar:





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Tonight's 00z gfs run should be interesting as in if it dies or develops.
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Quoting Hurricanes101:
gfs has yet to show what it shows in the 18Z, interesting development


for the record, I dont think that is 99L it is redeveloping, but a separate entity
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The blog is bored.
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Green Bay is getting hit by a severe warned cell.
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Quoting spathy:


LOL
Didnt you see my vid post of Martian heads exploding?
Things are active now so I cant post it.

Aqua turned me on to that clip.

But yes impending DOOM tends to spark my tongues!


No, I must have missed that one. I don't want to correct your Martian, but it is Ack...ack! Short pause in between. If you say Ack ack, it has an entirely different meaning. :)
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Member Since: July 3, 2005 Posts: 426 Comments: 129089
...........................looks like the storms are winding down thank goodness..3-4 more days like today the met said
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NAM shows a weak system over the Bahamas in 84 hrs:

Member Since: August 31, 2009 Posts: 0 Comments: 5628
Severe Thunderstorm Warning

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREEN BAY WI
544 PM CDT MON JUL 30 2012

WIC009-083-302315-
/O.CON.KGRB.SV.W.0076.000000T0000Z-120730T2315Z/
BROWN WI-OCONTO WI-
544 PM CDT MON JUL 30 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR OCONTO AND
NORTHWESTERN BROWN COUNTIES UNTIL 615 PM CDT...

AT 539 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A LINE OF SEVERE
THUNDERSTORMS PRODUCING UP TO 2 INCH SIZE HAIL. THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM OCONTO TO 10 MILES EAST OF
PULASKI...MOVING EAST AT 30 MPH.

IN ADDITION...AT 530 PM CDT...2 INCH HAIL WAS REPORTED NEAR THE TOWN
OF SOBIESKI.

SEVERE THUNDERSTORM WILL AFFECT THE LITTLE SUAMICO AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. MOVE TO AN INTERIOR ROOM OF YOUR HOME OR
BUSINESS. HEAVY RAINS CAN FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO
AREAS WHERE MOVING WATER COVERS THE ROAD.

&&

LAT...LON 4483 8809 4487 8797 4487 8782 4481 8790
4472 8798 4465 8797 4466 8799 4463 8800
4459 8797 4460 8801 4459 8802 4459 8824
TIME...MOT...LOC 2242Z 270DEG 27KT 4485 8787 4468 8800
WIND...HAIL <50MPH 1.75IN

$$

TH
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Quoting KEEPEROFTHEGATE:


i don't want to scare ya but there could be some type of dev in gom south of la offshore 3 or 4 days from now and maybe another area off east coast off sc and all the while a building 99l

remember sometimes things can pick up so fast we will not even be able to keep up



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Quoting Grothar:
Central Africa.


There is that cirrus off the the East African coast. Usually means that the wave train is in full swing.
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Ps srry if posted
MESOSCALE DISCUSSION 1654
NWS STORM PREDICTION CENTER NORMAN OK
0519 PM CDT MON JUL 30 2012

AREAS AFFECTED...MO BOOTHEEL...NERN AR...WRN TN AND NWRN MS

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 302219Z - 302345Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...TRENDS ARE BEING MONITORED FOR THUNDERSTORM
INTENSIFICATION FROM SERN MO INTO NERN AR. ISOLATED DAMAGING WIND
AND LARGE HAIL MAY BECOME POSSIBLE.
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Trying to wrap fully around


Lets not forget Damrey could also impact China and provide heavy rain.
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.........................wow winds really picking up now over on the east coast..dont we have a daytona poster in here sometimes?..how IS it over there?
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Quoting Grothar:


I don't believe it will go into the Gulf. It should on a pretty much WNW movement and be in the perhaps the Southern Bahamas not much chance for development at this time.

As a matter of fact, with the large ULL between the two systems, it could cause a little problem down the road if 99L gains a little latitude before it gains some attitude.


..ok ty
Member Since: August 6, 2011 Posts: 4 Comments: 40778
gfs has yet to show what it shows in the 18Z, interesting development
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Saola has left four dead and thousands displaced due to severe flooding in the Philippines. It's now setting its sights on Taiwan, and China after that:

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Quoting wxgeek723:
How about Allen in 1980? It's even the exact same time of the year too!
Allen was bad. Had some friends down in the Dry Tortugas back then...They regretted not leaving.
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Quoting spathy:


With that Avatar?
You dont want to scare me?
Too late!

And wholy crud!
I had no idea about home grown Doom!
..well way back in april the nws was warning about the coming season and to watch out for the home grown storms..so far they have been right on
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Quoting stormpetrol:
Shear is like knocking the head off and tradewinds knocks your feet from under you and you fall, that is best way I know to compare the 2, either way , you fall!


Good analogy
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Quoting GTcooliebai:
Look what comes off Africa at a rather high latitude.

Yeah I saw that and the low re-develops south of FL.
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Quoting wxchaser97:
276 hour
Look what comes off Africa at a rather high latitude.
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348 hours
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Quoting TropicalAnalystwx13:

I don't see it. Maybe post the previous run in addition to the current?
Sorry didn't know what you meant by not seeing it:

Yesterday:



Today:

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336 hours, impacting the Outer Banks
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336 hours:

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Cuz the link was bad and the address was broken by the WUforum-program
507 CaicosRetiredSailor: Human activities caused 70% to 95% of the Arctic sea ice loss
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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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