African tropical wave 99L has potential to develop

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

Share this Blog
49
+

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

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 1720 - 1670

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37Blog Index

1720. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Upper divergence


Lower convergence


99L is looking darn good for still only 20%.
Member Since: Posts: Comments:
Good Mourning tropical trouble ahead.

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT TUE JUL 31 2012

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

1. A WEAK AREA OF LOW PRESSURE ASSOCIATED WITH A TROPICAL WAVE LOCATED
ABOUT 1150 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS CONTINUES
TO PRODUCE DISORGANIZED SHOWER AND THUNDERSTORM ACTIVITY.
ENVIRONMENTAL CONDITIONS APPEAR CONDUCIVE FOR SOME GRADUAL
DEVELOPMENT OF THIS LOW OVER THE NEXT FEW DAYS. 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 KIMBERLAIN
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Quoting Pocamocca:

Is your current thinking that he might still stay north of PR and Hispaniola?


If it doesn't pull away from the ITCZ soon then it may just go south as the Euro and GFS are saying. The next 3 days are key but I also feel we have a sleeper wave near PR that people in FL better watch later this week as the wave looks really good this morning.

Could have our nerxt named system out of the mess near PR.

Member Since: Posts: Comments:
1715. LargoFl
Quoting PcolaSurf182:
Looks like some major action coming my way in Pensacola from the north. Had some awesome t-storms yesterday afternoon! Can't wait to see what today brings!
..yes my guess is warnings will go out for your area pretty soon, quite a nasty looking storm and large also
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1714. ncstorm
00z CMC



NOGAPS is still developing a system off of NC from a disturbance located near tennessee..





Member Since: August 19, 2006 Posts: 13 Comments: 15999
1713. LargoFl
going to have some warnings out later on in the southwest...............Heavy Monsoon Rain and Flash Floods Impacting the Southwest

The Monsoon is in full swing across portions of the Southwest and Great Basin early this week. Heavy rainfall from afternoon thunderstorms will have the potential to cause flash floods, debris flows and road washouts through at least Tuesday. A Flash Flood Watch is in effect for portions of southern Utah, southern Nevada, southeast California and western Arizona.
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Looks like some major action coming my way in Pensacola from the north. Had some awesome t-storms yesterday afternoon! Can't wait to see what today brings!
Member Since: Posts: Comments:
99L needs to pull away from the ITCZ so that it can develope more.

Member Since: Posts: Comments:
1708. LargoFl
................................Blob is still there off the carolina's
Member Since: August 6, 2011 Posts: 4 Comments: 40772
0Z CMC has a hurricane right on the east coast of FL.



Nogaps is near the Bahamas as well.

Member Since: Posts: Comments:
1706. LargoFl
Quoting Pocamocca:

Morning Largo.
..good morning
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1705. LargoFl
Quoting islander101010:
go.to.a.hospital.recently...half.the.doctors.are. indian.....they.dont.want.to.live.there
..sure must be crowded there huh
Member Since: August 6, 2011 Posts: 4 Comments: 40772
TROPICAL WAVES...

MID ATLC TROPICAL WAVE EXTENDS FROM 12N36W TO A 1010 MB LOW NEAR
9N37W MOVING W 5-10 KT. THE LOW IS EMBEDDED WITHIN THE MONSOON
TROUGH AND IS MOVING WSW 5-10 KT ALONG THE MONSOON TROUGH. LOW
IS EMBEDDED WITHIN THE DEEP MOISTURE OF THE MONSOON TROUGH AS
DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED
MODERATE/STRONG CONVECTION IS FROM 7N-11N BETWEEN 37W-42W.

TROPICAL WAVE EXTENDS FROM 22N67W INTO THE E CARIBBEAN ACROSS
THE MONA PASSAGE/DOMINICAN REPUBLIC ALONG 16N69W TO 12N67W
MOVING W 20-25 KT. WAVE IS ALONG THE LEADING EDGE OF A SURGE OF
DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER
IMAGERY. NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS ARE FROM
15N-19N BETWEEN 66W-70W. SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS COVER THE REMAINDER OF THE AREA FROM 15N TO OVER
THE LEEWARD ISLANDS TO PUERTO RICO BETWEEN 61W-70W.
Member Since: Posts: Comments:
Quoting LargoFl:
.gee somehow that country needs to improve its power plants enough to withstand bad storms huh..cannot imagine almost a whole country without power..simply amazing that could happen
go.to.a.hospital.recently...half.the.doctors.are. indian.....they.dont.want.to.live.there
Member Since: Posts: Comments:
1700. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1698. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1697. LargoFl
..............................I wonder what will happen when this bad storm gets into the northern gulf?
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1696. LargoFl
Quoting Neapolitan:
Incredible, huh? It's the single largest power failure in history...
.gee somehow that country needs to improve its power plants enough to withstand bad storms huh..cannot imagine almost a whole country without power..simply amazing that could happen
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Quoting naviguesser:


My math has 1.2B/2 = 600M people. US is just over 300M people. So just under twice the population of the entire US has no power.
Incredible, huh? It's the single largest power failure in history...
Member Since: Posts: Comments:
Quoting naviguesser:


My math has 1.2B/2 = 600M people. US is just over 300M people. So just under twice the population of the entire US has no power.


Yesterday it was 370 million people.
Member Since: Posts: Comments:
Quoting SLU:


Doesn't feel like an El Nino-like year doesn't it?



El nino? Really? This is a el nino year? Couldn't tell
Member Since: Posts: Comments:
Quoting Neapolitan:
For the second consecutive day, parts of India's power grid have suffered massive failures, knocking out electricity to about half of the country's 1.2 billion residents. Hundreds of trains were brought to a halt; traffic lights are out, leading to major traffic problems; there's no air conditioning, especially rough for this time of year. The weak monsoon has led to lowered hydroelectric generation, while at the same time it's kept the temperatures hotter, meaning an even greater demand on the electrical grid.

Now, if that doesn't sound all the bad, consider: that would be equivalent to a blackout here in the U.S. affecting every single person in California, Texas, New York, Florida, Illinois, Pennsylvania, Ohio, Michigan, Georgia, and North Carolina. At the same time. In the middle of summer.


My math has 1.2B/2 = 600M people. US is just over 300M people. So just under twice the population of the entire US has no power.
Member Since: Posts: Comments:
Member Since: Posts: Comments:
1690. LargoFl
.........................GFS at 60 hours with rainfall
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1688. LargoFl
..............just look at what that tropical wave will meet..gee,gasoline for a storm
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1687. SLU
Quoting stoormfury:
ECMWF is showing a strong disturbace in thr catl on the 9th august, and a stroger one about to exit the african coast.


Doesn't feel like an El Nino-like year doesn't it?
Member Since: Posts: Comments:
1686. LargoFl
Quoting GeoffreyWPB:


The latest model runs are from 8:00 p.m. last night?
..yes i think so
Member Since: August 6, 2011 Posts: 4 Comments: 40772
1685. LargoFl
Quoting GeoffreyWPB:
Miami NWS Discussion

A TROPICAL WAVE OVER THE LEEWARD ISLANDS AND PUERTO RICO WILL MOVE
TOWARDS CUBA AND THE BAHAMAS ON THURSDAY. PWATS ARE STILL EXPECTED
TO REMAIN AROUND THE 25TH PERCENTILE...SO POPS WILL REMAIN
RELATIVELY LOW. ISOLATED CONVECTION IS EXPECTED FOR THE METRO AREAS
AND SCATTERED STORMS ACROSS THE INTERIOR. THE LEADING EDGE OF THE
TROPICAL WAVE MAY MOVE INTO SOUTH FLORIDA AROUND DAYBREAK ON
FRIDAY...WITH PWATS INCREASING TO AROUND 2 INCHES BY THE AFTERNOON.
SO INCREASING RAIN CHANCES ARE EXPECTED FRIDAY AND SATURDAY AS THE
WAVE MOVES ACROSS THE REGION...WITH SCATTERED TO POSSIBLY NUMEROUS
SHOWERS AND STORMS.
..............so this might be the wave they were expecting to move into the gulf..we need to watch That one for sure..water temps in the gulf are mid 80's
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Quoting LargoFl:
................IF..99L follows the path the GFS says it will..its not our storm,unless it makes an abrupt right hand turn once it passes the islands


The latest model runs are from 8:00 p.m. last night?
Member Since: Posts: Comments:
1683. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Good morning. Impressive vorticity.

Member Since: Posts: Comments:
Miami NWS Discussion

A TROPICAL WAVE OVER THE LEEWARD ISLANDS AND PUERTO RICO WILL MOVE
TOWARDS CUBA AND THE BAHAMAS ON THURSDAY. PWATS ARE STILL EXPECTED
TO REMAIN AROUND THE 25TH PERCENTILE...SO POPS WILL REMAIN
RELATIVELY LOW. ISOLATED CONVECTION IS EXPECTED FOR THE METRO AREAS
AND SCATTERED STORMS ACROSS THE INTERIOR. THE LEADING EDGE OF THE
TROPICAL WAVE MAY MOVE INTO SOUTH FLORIDA AROUND DAYBREAK ON
FRIDAY...WITH PWATS INCREASING TO AROUND 2 INCHES BY THE AFTERNOON.
SO INCREASING RAIN CHANCES ARE EXPECTED FRIDAY AND SATURDAY AS THE
WAVE MOVES ACROSS THE REGION...WITH SCATTERED TO POSSIBLY NUMEROUS
SHOWERS AND STORMS.
Member Since: Posts: Comments:
1680. LargoFl
................................OMG..floridians in the panhandle LISTEN to your local warnings and stay safe up there,this looks bad huh
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Quoting stoormfury:
ECMWF is showing a strong disturbace in thr catl on the 9th august, and a stroger one about to exit the african coast.



That's what y call a wave train.... bout time
Member Since: Posts: Comments:
Quoting stoormfury:
ECMWF is showing a strong disturbace in thr catl on the 9th august, and a stroger one about to exit the african coast.


Yep and 99l in the gulf.

Member Since: Posts: Comments:
1677. LargoFl
................IF..99L follows the path the GFS says it will..its not our storm,unless it makes an abrupt right hand turn once it passes the islands
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Red sky by morning here in the Northwest Florida Panhandle!
Member Since: Posts: Comments:
For the second consecutive day, parts of India's power grid have suffered massive failures, knocking out electricity to about half of the country's 1.2 billion residents. Today's event is the single largest power failure ever in the history of the world. Hundreds of trains were brought to a halt; traffic lights are out, leading to major traffic chaos; there's no air conditioning, especially rough for this time of year. And so on. The disrupted monsoon has led to lowered hydroelectric generation, while at the same time it's kept the temperatures hotter, meaning an even greater demand on the electrical grid.

Now, if that doesn't sound all the bad, consider: proportionally speaking, that would be equivalent to a blackout here in the U.S. affecting every single person in California, Texas, New York, Florida, Illinois, Pennsylvania, Ohio, Michigan, Georgia, and North Carolina. At the same time. In the middle of summer.
Member Since: Posts: Comments:
ECMWF is showing a strong disturbace in thr catl on the 9th august, and a stroger one about to exit the african coast.
Member Since: Posts: Comments:
1673. LargoFl
THIS HAZARDOUS WEATHER OUTLOOK IS FOR WEST CENTRAL AND SOUTHWEST
FLORIDA.

.DAY ONE...TODAY AND TONIGHT.

...THUNDERSTORM IMPACT...
ISOLATED THUNDERSTORMS ARE EXPECTED TO FORM THIS MORNING ALONG
COASTAL LOCATIONS AND THEN DRIFT INLAND IN THE AFTERNOON...WITH
SCATTERED COVERAGE ACROSS THE NORTH AND THE CENTRAL AND SOUTHERN
INTERIOR. THUNDERSTORMS MAY BE ESPECIALLY STRONG IN HERNANDO...
CITRUS...SUMTER...AND LEVY COUNTIES. GUSTY WINDS...LOCALLY HEAVY
RAINFALL...AND DEADLY CLOUD TO GROUND LIGHTNING WILL BE THE MAIN
HAZARDS WITH THE STORMS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

...THUNDERSTORM IMPACT...
SCATTERED THUNDERSTORMS ARE EXPECTED EACH DAY...SCATTERED DURING
THE DAYTIME AND ISOLATED OVERNIGHT. THESE STORMS MAY PRODUCE
GUSTY WINDS...LOCALLY HEAVY RAINFALL...AND DEADLY CLOUD TO GROUND
LIGHTNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY.
Member Since: August 6, 2011 Posts: 4 Comments: 40772
Quoting mcluvincane:



Very good for drought areas


Ah. Then there is a silver lining. :)
Member Since: Posts: Comments:
Quoting LargoFl:
wow thats alot of rain but i think someone said they were needing rain, this should help them out if they dont get too much flooding, the blob isnt a fast mover
sign.theres.available.energy.for.further.downstre am
Member Since: Posts: Comments:
Quoting AtHomeInTX:


That can't be good.



Very good for drought areas
Member Since: Posts: Comments:

Viewing: 1720 - 1670

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Overcast
49 °F
Overcast