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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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: 39134
1069. Patrap
I hope press is wearing Jeans SJ.
Member Since: July 3, 2005 Posts: 426 Comments: 128639
1068. Patrap
Member Since: July 3, 2005 Posts: 426 Comments: 128639
Preacherman said it's the end of time
and the Mississippi river she's going dry
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1066. LargoFl
wow..lets add yet another state to our storm party tonight....................BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MEMPHIS TN
656 PM CDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN MEMPHIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN CLAY COUNTY IN EASTERN ARKANSAS...
NORTHEASTERN GREENE COUNTY IN EASTERN ARKANSAS...

* UNTIL 745 PM CDT

* AT 657 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH.
THIS STORM WAS LOCATED 9 MILES NORTHWEST OF RECTOR...AND MOVING
SOUTHEAST AT 20 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO GREENWAY
AND RECTOR.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

.STAY TUNED TO THIS BROADCAST FOR THE LATEST UPDATES AND INFORMATION.
TO REPORT SEVERE WEATHER ONLY...CALL 1 800 4 3 2 0 8 7 5.



LAT...LON 3628 9008 3627 9009 3627 9011 3622 9015
3617 9023 3615 9023 3612 9027 3634 9049
3643 9040
TIME...MOT...LOC 2357Z 306DEG 18KT 3635 9040
Member Since: August 6, 2011 Posts: 4 Comments: 39134
99L is popping for us tonight..now only if it could gain some latitude or else this baby is going into S.A.
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For the central north Pacific, between 140°W and 180.

1. A well-defined surface trough about 400 miles south of Kona Hawaii is moving toward the west near 20 mph. Although isolated thunderstorms have been occasionally developing in association with the trough, environmental conditions are not conducive for intensification. There is a low chance, near 0 percent, of this system becoming a tropical cyclone during the next 48 hours.
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Out for now. Peace.
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Very electrical storm about to hit Buzzards roost marina. Live Feed.

And presslord is here with me.
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wunderground time now lol
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Member Since: July 21, 2011 Posts: 83 Comments: 7167
Member Since: March 16, 2012 Posts: 127 Comments: 7948
1058. LargoFl
Quoting GeoffreyWPB:


You are right. 99L has a lot of work to do. Tenuous to say the least.
..yes for right now just something to watch
Member Since: August 6, 2011 Posts: 4 Comments: 39134
Quoting wxchaser97:
An el nino wont help in the north since we see less snow which would not be good for the drought situation.
Usually El nino helps with my region and the south.So we should see some improvement there.You all are going to need..Dare I say it?.Another La nina!.
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Quoting Hurricanes101:


looks pretty well organized to me, I would have gone with 30% considering many of the models develop it within the next 36-72 hours
Quoting TropicalAnalystwx13:

Still, I would have went up to 30%.
Quoting washingtonian115:
I would have given 30% for organization,and wait to give it a higher percentage when it detaches from the caribbean.


I'm giving you guys their reasoning, not mine. We aren't going to see them designate a tropical cyclone within the ITCZ. It needs to become its own entity and persist without the ITCZ's help. In reality, there is 0% chance of them designating it in the next 48 hours since they like to see it persist after departing from the ITCZ.
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1055. LargoFl
wow..ping pong ball size Hail................................BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREEN BAY WI
653 PM CDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN GREEN BAY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHERN KEWAUNEE COUNTY IN NORTHEAST WISCONSIN...
NORTHEASTERN MANITOWOC COUNTY IN EAST CENTRAL WISCONSIN...

* UNTIL 730 PM CDT

* AT 653 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING PING PONG BALL SIZE HAIL.
THIS STORM WAS LOCATED 8 MILES SOUTHWEST OF LUXEMBURG...OR 12 MILES
SOUTHEAST OF GREEN BAY...AND MOVING SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
KEWAUNEE AROUND 720 PM CDT.
TWO CREEKS AROUND 725 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS SEVERE THUNDERSTORM INCLUDE
CURRAN...ELLISVILLE...STANGELVILLE...BOLT...KROK. ..EAST KROK...
BIRCHWOOD...TISCH MILLS...NORMAN AND KEWAUNEE POWER STATION.

THIS WARNING EXTENDS THE SEVERE THUNDERSTORM WARNING THAT WAS
IN EFFECT FOR KEWAUNEE COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...AND DEADLY
LIGHTNING. FOR YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE
LOWEST FLOOR OF YOUR HOME OR BUSINESS.
Member Since: August 6, 2011 Posts: 4 Comments: 39134
Quoting MAweatherboy1:

Great minds think alike, lol.


Yep. lol.
Member Since: July 21, 2011 Posts: 83 Comments: 7167
It will be interesting to see what 99L looks like this time tomorrow. Only at 20% at the moment but the overall organization appears to be improving right at about the 8N-38W mark on the water vapor loop (below). If that area gains some latitude over the next 48 hours, it could develop further.

Link
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1052. Grothar
Some model intensities going up a little.

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Quoting LargoFl:
..but will 99L seperate from the storm in front and back of it enough to really form into something


You are right. 99L has a lot of work to do. Tenuous to say the least.
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Quoting MAweatherboy1:
Convection is building:



Link
Quoting Civicane49:
.

Great minds think alike, lol.
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1049. LargoFl
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BLACKSBURG VA
750 PM EDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN BLACKSBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
NORTHEASTERN BATH COUNTY IN WEST CENTRAL VIRGINIA

* UNTIL 830 PM EDT.

* AT 745 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING ONE INCH DIAMETER HAIL...
AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED
NEAR BURNSVILLE...OR 11 MILES NORTHEAST OF WARM SPRINGS...AND
MOVING NORTHWEST AT 10 MPH.

* LOCATIONS IMPACTED INCLUDE...
BURNSVILLE...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER.

REMEMBER...A SEVERE THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...
DAMAGING WINDS IN EXCESS OF 55 MPH...DEADLY LIGHTNING...AND VERY
HEAVY RAIN.

LARGE HAIL AND...OR STRONG DAMAGING WINDS ARE LIKELY WITH THIS STORM.
IN ADDITION...TORRENTIAL RAINS MAY FLOOD LOW LYING AREAS SUCH AS
DITCHES AND UNDERPASSES. DO NOT DRIVE INTO AREAS WHERE WATER COVERS
THE ROAD!

WHEN IT IS SAFE TO DO SO...PLEASE SEND YOUR REPORTS OF QUARTER OR
LARGER SIZED HAIL...AS WELL AS WIND DAMAGE...INCLUDING TREES OR LARGE
LIMBS DOWNED BY CALLING THE NATIONAL WEATHER SERVICE TOLL FREE AT...
1...8 6 6...2 1 5...4 3 2 4.
Member Since: August 6, 2011 Posts: 4 Comments: 39134
.
Member Since: July 21, 2011 Posts: 83 Comments: 7167
Convection is building:



Link
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Quoting JLPR2:


That's probably the reason why it is slowly organizing, if it where more to the north it would be dry and shred to pieces.

Shred to pieces by what? The shear that doesn't exist? XD
Member Since: July 6, 2010 Posts: 113 Comments: 32258
1045. LargoFl
Quoting GeoffreyWPB:
..but will 99L seperate from the storm in front and back of it enough to really form into something
Member Since: August 6, 2011 Posts: 4 Comments: 39134
1044. icmoore
Quoting Grothar:


Very few of my friends know I track the weather. The few who do, tease the heck out of me. If a storm is threatening, they call here and ask for Weather Central. Or if some are planning and outing, they say, "We better check with .... (real name deleted) first".


:) 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 :)
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Quoting washingtonian115:
And it has also contributed to the wide spread drought.
An el nino wont help in the north since we see less snow which would not be good for the drought situation.
Member Since: March 16, 2012 Posts: 127 Comments: 7948
Hurricane Field Program Update – Monday, July 30, 2012 4:47 PM Eastern

OPERATIONS

NOAA P-3s

NOAA-42: NOAA42 flew a research instrumentation test flight today. This flight allowed for testing the new radar data system and the dropsonde processing software. Along with AOC, we are gearing up for this season.

Want to learn more on our flight experiments this year? Check out our Hurricane Field Program Plan.

Link
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Quoting Civicane49:
Looks like a rip apart funnel cake.Lol.And the disturbance behind it also has a nice spin to it.
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1039. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 39134
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Member Since: July 21, 2011 Posts: 83 Comments: 7167
Quoting Patrap:
Lack of Snow during winter and lack of Spring Rains have all combined to create a Low Miss River.

One can actually see 2 sandbars in the Miss River here at the Bienville Street Wharf..with Birds standing on them.
And it has also contributed to the wide spread drought.
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1035. etxwx
Insurance losses in Beijing storm climb to 500 million yuan
BEIJING, July 30 (Xinhua) -- Insured losses resulting from a severe rainstorm that hit Beijing on July 21 have climbed to about 900 million yuan (141 million U.S. dollars), the city's insurance regulatory commission said Monday. Losses reported by the end of Saturday included 370 million yuan for 41,000 auto insurance claims and 440 million yuan in asset insurance claims, the commission said. Compensation payments for personal insurance cases are expected to reach 4.49 million yuan, the commission said. The storm, one of the heaviest in decades, killed at least 77 people in Beijing, according to the municipal government.
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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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1033. Patrap

Member Since: July 3, 2005 Posts: 426 Comments: 128639
1032. LargoFl
.................good to see south florida getting some rain finally
Member Since: August 6, 2011 Posts: 4 Comments: 39134
18z GFS ensemble mean was similar to the GFS itself:



My blog from earlier if you missed it.
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1030. Patrap
Lack of Snow during winter and lack of Spring Rains have all combined to create a Low Miss River.

One can actually see 2 sandbars in the Miss River here at the Bienville Street Wharf..with Birds standing on them.
Member Since: July 3, 2005 Posts: 426 Comments: 128639
Quoting washingtonian115:
I would have given 30% for organization,and wait to give it a higher percentage when it detaches from the caribbean.
Exactly what I would have done.
Member Since: March 16, 2012 Posts: 127 Comments: 7948
Quoting LargoFl:
ok ty


No problem.
Member Since: July 21, 2011 Posts: 83 Comments: 7167
1027. JLPR2
Quoting MississippiWx:
I mentioned this earlier, but you're not going to see the NHC jump on 99L's bandwagon too much until it departs from the ITCZ. It's still very far to the south and very much embedded within the convergence zone.



That's probably the reason why it is slowly organizing, if it where more to the north it would be dry and shred to pieces.
Member Since: September 4, 2007 Posts: 7 Comments: 8733
Quoting Grothar:


Looks like its coming together pretty good.


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.
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1025. LargoFl
Quoting Civicane49:


99L is still attached to the Intertropical Convergence Zone (ITCZ), and it is in a latitude where there is weak atmospheric spin. Once 99L is detached from the ITCZ and gains more latitude, it'll likely start further development if conditions are favorable.
ok ty
Member Since: August 6, 2011 Posts: 4 Comments: 39134
Quoting TropicalAnalystwx13:

Still, I would have went up to 30%.
Quoting Hurricanes101:


looks pretty well organized to me, I would have gone with 30% considering many of the models develop it within the next 36-72 hours
Quoting washingtonian115:
I would have given 30% for organization,and wait to give it a higher percentage when it detaches from the caribbean.

Lol.
Member Since: July 6, 2010 Posts: 113 Comments: 32258
Quoting LargoFl:
..still does not look like its coming together, maybe thats why they kept it at 20%


99L is still attached to the Intertropical Convergence Zone (ITCZ), and it is in a latitude where there is weak atmospheric spin. Once 99L is detached from the ITCZ and gains more latitude, it'll likely start further development if conditions are favorable.
Member Since: July 21, 2011 Posts: 83 Comments: 7167
I would have given 30% for organization,and wait to give it a higher percentage when it detaches from the caribbean.
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1021. LargoFl
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
438 PM PDT MON JUL 30 2012

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
SOUTHWESTERN IMPERIAL COUNTY IN SOUTHEAST CALIFORNIA...
THIS INCLUDES PLASTER CITY...OCOTILLO...IMPERIAL...EL CENTRO...
CALEXICO...BRAWLEY...

* UNTIL 730 PM PDT

* AT 434 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
THUNDERSTORMS WITH VERY HEAVY RAIN 15 MILES NORTHWEST OF PLASTER
CITY. ADDITIONAL THUNDERSTORMS WITH HEAVY RAIN WERE SOUTH OF EL
CENTRO AND SOUTHEAST OF OCOTILLO. MOVEMENT WAS SOUTHEAST AT
15 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WESTMORLAND

RADAR INDICATES THAT THE STORMS HAVE PRODUCED UP TO 2 INCHES OF RAIN
SINCE 330 PM. RUNOFF FROM THE HEAVY RAIN WILL PRODUCE STREET
FLOODING...AND WILL AFFECT FISH WASH...CARRIZO WASH....AND SAN
FELIPE CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT PEOPLE ALONG THE BANKS OF WASHES AND
CREEKS SHOULD MOVE TO HIGHER GROUND IMMEDIATELY. NORMALLY DRY WASHES
AND STREAMS WILL SUDDENLY HAVE RUNNING WATER AND MAKE UNBRIDGED
CROSSINGS IMPASSABLE. STREETS...UNDERPASSES...AND LOW SPOTS WILL
BECOME INUNDATED MAKING DRIVING HAZARDOUS IN THE WARNED AREA.

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

TO REPORT FLOODING...PLEASE RELAY YOUR REPORT TO LOCAL LAW
ENFORCEMENT WHEN YOU CAN DO SO SAFELY.
Member Since: August 6, 2011 Posts: 4 Comments: 39134

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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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