The tropics are quiet

By: Dr. Jeff Masters , 1:11 PM GMT on September 06, 2009

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Considering that this is historically the peak week of the Atlantic hurricane season, the tropics are quiet. There is an area of disturbed weather in the middle Atlantic (95L) that NHC has been mentioning in their Tropical Weather Outlook the past day, but this disturbance is entering a region of high wind shear and is not a threat to develop.

A strong tropical wave with plenty of rotation is emerging off the coast of Africa this morning, and this wave is a good candidate to show some development this week as it heads west-northwest over the Atlantic. The wave is under about 15 knots of wind shear, and is being developed by several models, including the GFS and ECMWF. However, the models show that this new wave will be pulled northwestward by a strong trough of low pressure this week, and it appears unlikely that the wave will make the long crossing of the Atlantic necessary to threaten any land areas. Another wave with plenty of spin will emerge from the coast of Africa two days from now, and will also have a chance to develop.


Figure 1. Morning satellite image of 95L and a new tropical wave with potential to develop, emerging from the coast of Africa.

An area of concentrated thunderstorms has developed off the North Carolina coast in association with the remains of an old cold front. This system is under about 20 - 30 knots of shear, and is not tropical. However, it will bring heavy rain just offshore of North Carolina's Outer Banks today as it slides north-northeastward along the coast.

I'll have an update Monday.

Jeff Masters

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1044. IKE
Quoting Stormchaser2007:
Nothing has changed in the TWO.

No update needed.


They took off the yellow circle off of the Carolina's. So much for Bastardi's thoughts on that blob.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1043. BGMom
Quoting Magicchaos:
Anyone remember the overhyped "Megastorm" that was supposed to hit around Groundhog day this year? Went too far east to bring a major snowstorm for the Northeast.


I am just Northwest of Atlanta and every year we PRAY for a decent snow that will last more than 5 minutes.
Member Since: Posts: Comments:
Quoting Tazmanian:
oh yes there was



Color Taz.

;)
Member Since: June 9, 2007 Posts: 4 Comments: 15718
1041. hydrus
Quoting Seasidecove:


A: Yes, tropical storms and weak hurricanes both have moved through the Cape Verde Islands. The most recent year with a storm was 1989. Tropical Storm Felix's center passed just north of the Cape Verde Islands in late August. But, no tropical storms or hurricanes on record has ever survived recurving back into Africa.

The Cape Verde islands off Africa's west coast are a breeding ground for many of the USA's worst hurricanes. Isabel is one of these so-called "Cape Verde" hurricanes, which grow from blobs of thunderstorms as soon as they move off the African continent and over the warm tropical ocean near the islands. Most of them pass south of the Cape Verde islands, and a majority become tropical depressions or tropical storms west of the islands. Most of these continue to move west, but occasionally a storm quickly curves northward and brings tropical storm winds of 39-73 mph or, much more rarely, hurricane winds of 74 mph or higher to the islands.

(Answered by Chris Cappella, USATODAY.com Weather Team, Sept. 17, 2003)

Thank you.
Member Since: Posts: Comments:
oh yes there was

Quoting Tazmanian:
000
ABNT20 KNHC 062335
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SUN SEP 6 2009

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

A STRONG TROPICAL WAVE LOCATED ABOUT 300 MILES EAST-SOUTHEAST OF THE
CAPE VERDE ISLANDS IS PRODUCING NUMEROUS SHOWERS AND THUNDERSTORMS.
CONDITIONS APPEAR FAVORABLE FOR DEVELOPMENT OF THIS SYSTEM...AND A
TROPICAL DEPRESSION COULD FORM DURING THE NEXT COUPLE OF DAYS AS IT
MOVES WESTWARD OR WEST-NORTHWESTWARD AT AROUND 15 MPH. THERE IS A
MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
Member Since: May 21, 2006 Posts: 5089 Comments: 114051
Quoting zoomiami:


Also, to this day there are people who will swear that the reason they closed off the base was due to the hundreds of casualties that were housed in the hangers. Always amazes me that people still believe this.
Yeah I read something about conspiracy theories being debunked by the Herald.... turns out the people from the 31st Fighter Wing only moved to Central FL and GA. So I guess they stayed in the hurricane belt after all..... lol
Member Since: October 25, 2005 Posts: 19 Comments: 20695
Nothing has changed in the TWO.

No update needed.
Member Since: June 9, 2007 Posts: 4 Comments: 15718
Quoting hydrus:
I wonder if the Cape Verde Islands have ever had a hurricane?


A: Yes, tropical storms and weak hurricanes both have moved through the Cape Verde Islands. The most recent year with a storm was 1989. Tropical Storm Felix's center passed just north of the Cape Verde Islands in late August. But, no tropical storms or hurricanes on record has ever survived recurving back into Africa.

The Cape Verde islands off Africa's west coast are a breeding ground for many of the USA's worst hurricanes. Isabel is one of these so-called "Cape Verde" hurricanes, which grow from blobs of thunderstorms as soon as they move off the African continent and over the warm tropical ocean near the islands. Most of them pass south of the Cape Verde islands, and a majority become tropical depressions or tropical storms west of the islands. Most of these continue to move west, but occasionally a storm quickly curves northward and brings tropical storm winds of 39-73 mph or, much more rarely, hurricane winds of 74 mph or higher to the islands.

(Answered by Chris Cappella, USATODAY.com Weather Team, Sept. 17, 2003)

Member Since: Posts: Comments:
thanks bahahurricane had heard about an online school but had not seen it yet. thanks!
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1034. IKE
Quoting jipmg:


well the below average air get into Florida


It should eventually.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
000
ABNT20 KNHC 062335
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SUN SEP 6 2009

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

A STRONG TROPICAL WAVE LOCATED ABOUT 300 MILES EAST-SOUTHEAST OF THE
CAPE VERDE ISLANDS IS PRODUCING NUMEROUS SHOWERS AND THUNDERSTORMS.
CONDITIONS APPEAR FAVORABLE FOR DEVELOPMENT OF THIS SYSTEM...AND A
TROPICAL DEPRESSION COULD FORM DURING THE NEXT COUPLE OF DAYS AS IT
MOVES WESTWARD OR WEST-NORTHWESTWARD AT AROUND 15 MPH. THERE IS A
MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
Member Since: May 21, 2006 Posts: 5089 Comments: 114051
I'm out for tonight

See ya guys.
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Quoting InTheCone:


Very interesting post! Thanks!


Thanks

wow...it looks like 12Z ECMWF is expecting a similar case scenario...I did not realize that.
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1030. hydrus
Quoting iceman55:
hydrus Storm surge kill lot of people :( so sad
I think they said 3 were killed but the news about the storm was sloppy because of its spontanaity, either way it sure made a mess of the place in a short amount of time.
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Quoting BahaHurican:
Just reading the wiki on Andrew and came across this:

Massive damage caused by Andrew at Homestead Air Force Base, very near the point of landfall on the South Florida coast, led to the closing of the base as a full active-duty base. It was later partly rebuilt and operates today as a U.S. Air Reserve base. The aircraft and squadron were relocated to Aviano Air Base in Italy.

This made me smile, because I was thinking how Andrew was so tough for the squadron that had been stationed at Homestead that they left the entire basin so they could avoid the possibility of another TC..... lol


Also, to this day there are people who will swear that the reason they closed off the base was due to the hundreds of casualties that were housed in the hangers. Always amazes me that people still believe this.
Member Since: Posts: Comments:
Quoting BahaHurican:
Just reading the wiki on Andrew and came across this:

Massive damage caused by Andrew at Homestead Air Force Base, very near the point of landfall on the South Florida coast, led to the closing of the base as a full active-duty base. It was later partly rebuilt and operates today as a U.S. Air Reserve base. The aircraft and squadron were relocated to Aviano Air Base in Italy.

This made me smile, because I was thinking how Andrew was so tough for the squadron that had been stationed at Homestead that they left the entire basin so they could avoid the possibility of another TC..... lol


Interesting side note: my kids medical records were at the base, had to get them from McDill where everything was sent to try and salvage.
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Quoting futuremet:
Bonsoir everyone


It looks like we will have to monitor the GOM closely during the latter part of next week, as a potent longwave trough traverses across the Midwest. The trough is expected to split and slightly troughing in southward, thus kindling upper level anticyclogenesis across the area. The anticyclone will form due to positive vorticity advection at the eastern axis of the longwave trough. Like fluids, air has a tendency to rotate at its own axis, and typically flows from areas of higher speed to lower speed. Therefore some the fast moving air moving from the southwest will start curving toward the south. This is why upper level anticyclones typically form proportionally by the area of highest winds along the trough axis. The formation of the upper ridge will help decrease wind shear values over the GOM, which will great tropical cyclone formation. Since upper level ridges do not have a pronounced effect on steering current, the longwave trough to the north will likely steer anything that forms NE. Now, I am not saying anything will form, but there is a possibility something will. This may very well be the last chance for anything to form in the GOM, before it closes down in October due to shear. The anomalously warm SSTs in the GOM will propagate southward to the Caribbean as we near the month of October. In addition, the MJO will help increase values across the Caribbean. Troughs nosing in southward will provide additional energy for tropical cyclone formation; like in hurricane Wilma of 2005. Hopefully this weak el nino will induce adequate shear to stop anything major from forming; or hopefully the troughs are so strong that the cause these storms to move ENE , like we saw in latter part of 2008 with Omar and Paloma.

Strong Upper level ridge

Image and video hosting by TinyPic

Low Shear

<>img src="Image and video hosting by TinyPic" alt="" />


Very interesting post! Thanks!
Member Since: Posts: Comments:
Just reading the wiki on Andrew and came across this:

Massive damage caused by Andrew at Homestead Air Force Base, very near the point of landfall on the South Florida coast, led to the closing of the base as a full active-duty base. It was later partly rebuilt and operates today as a U.S. Air Reserve base. The aircraft and squadron were relocated to Aviano Air Base in Italy.

This made me smile, because I was thinking how Andrew was so tough for the squadron that had been stationed at Homestead that they left the entire basin so they could avoid the possibility of another TC..... lol
Member Since: October 25, 2005 Posts: 19 Comments: 20695
1024. KEEPEROFTHEGATE (Mod)


AOI/XX/XX
MARK
22.7N/93.8W
Member Since: July 15, 2006 Posts: 163 Comments: 52257
1023. hydrus
Quoting iceman55:
kill hundred.115
We took a good hit in 82 by an unnamed sub-tropical storm. We had gusts to 90 mph. It came up suddenly and alot of people were not prepared for the surge which was substantial and effected a large portion of the West coast of Florida.
Member Since: Posts: Comments:
Bonsoir everyone


It looks like we will have to monitor the GOM closely during the latter part of next week, as a potent longwave trough traverses across the Midwest. The trough is expected to split and slightly troughing in southward, thus kindling upper level anticyclogenesis across the area. The anticyclone will form due to positive vorticity advection at the eastern axis of the longwave trough. Like fluids, air has a tendency to rotate at its own axis, and typically flows from areas of higher speed to lower speed. Therefore some the fast moving air moving from the southwest will start curving toward the south. This is why upper level anticyclones typically form proportionally by the area of highest winds along the trough axis. The formation of the upper ridge will help decrease wind shear values over the GOM, which will great tropical cyclone formation. Since upper level ridges do not have a pronounced effect on steering current, the longwave trough to the north will likely steer anything that forms NE. Now, I am not saying anything will form, but there is a possibility something will. This may very well be the last chance for anything to form in the GOM, before it closes down in October due to shear. The anomalously warm SSTs in the GOM will propagate southward to the Caribbean as we near the month of October. In addition, the MJO will help increase values across the Caribbean. Troughs nosing in southward will provide additional energy for tropical cyclone formation; like in hurricane Wilma of 2005. Hopefully this weak el nino will induce adequate shear to stop anything major from forming; or hopefully the troughs are so strong that the cause these storms to move ENE , like we saw in latter part of 2008 with Omar and Paloma.

Strong Upper level ridge

Image and video hosting by TinyPic

Low Shear

<>img src="Image and video hosting by TinyPic" alt="" />
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1021. Patrap
96L 2km Storm Relative IR Imagery with BD Enhancement Curve

2230 UTC

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1019. Patrap
Early-Track Guidance AL 96
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Quoting iceman55:
Tropical Storm Beryl in 1982 is notable. Killed i think ??? help me out


Killed over a hundred.

EDIT: Actually, turns out that injured hundreds, but only killed three.
Member Since: March 7, 2007 Posts: 521 Comments: 19119
Quoting zebralove:
thank you koritheman I know so little yet that it is even hard to figure out where to look to find answers to my questions, I only knew 92 and 02 were el nino years because of a post earlier in the blog. I wish there was a really good page to look at for beginers to learn stuff. I am trying to learn it all in a very unorganized fashion it seems. Learning to read the charts, the lingo, the abreviations used, the basic formation and cloud types..... you name it I'm trying to learn it but it is really hard not even knowing really where to look. I thank everyone on WU who answers questions and helps point me in the right direction!!!
Try this.
Member Since: October 25, 2005 Posts: 19 Comments: 20695
Quoting HurricaneKyle:


Absolutely excellent Chaser!!


Thanks!
Member Since: June 9, 2007 Posts: 4 Comments: 15718
Anyone remember the overhyped "Megastorm" that was supposed to hit around Groundhog day this year? Went too far east to bring a major snowstorm for the Northeast.
Member Since: Posts: Comments:
1011. jipmg
Quoting Dakster:


Sort of. It might knock out some humidity...

I'd like to see snow in South Florida again. Although I don't think that will happen until the next ice age.


imagine how cold this winter is going to be if we get a Front moving through in summer..
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1010. Dakster
Quoting iceman55:
Tropical Storm Beryl in 1982 is notable. Killed i think ??? help me out


Beryl in 1982 didn't make landfall. I doubt it killed that many people, if any.
Member Since: March 10, 2006 Posts: 0 Comments: 9700
1009. hydrus
Quoting JLPR:


now that's a good question
I would bet they get there share of rough weather this time of year with all those T-waves. I do remember those Islands getting tropical storm warnings.
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Quoting Stormchaser2007:
Repost.

6pm tropical update on 96L and NC disturbance.


Absolutely excellent Chaser!!
Member Since: August 10, 2009 Posts: 3 Comments: 672
1006. Dakster
Quoting jipmg:


so we are getting a cold front into southern florida in September..


Sort of. It might knock out some humidity...

I'd like to see snow in South Florida again. Although I don't think that will happen until the next ice age.
Member Since: March 10, 2006 Posts: 0 Comments: 9700
1004. JLPR
Quoting hydrus:
I wonder if the Cape Verde Islands have ever had a hurricane?


now that's a good question
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Repost.

6pm tropical update on 96L and NC disturbance.
Member Since: June 9, 2007 Posts: 4 Comments: 15718
1002. hydrus
Quoting JLPR:


seems reasonable

at least we get some entertainment in the Atlantic xD
I just hope it doesn't put the CVs in danger
I wonder if the Cape Verde Islands have ever had a hurricane?
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1001. jipmg
Quoting Dakster:


Yes, we are going to have lows in the upper 80's, wohoo! Can hardly wait.


so we are getting a cold front into southern florida in September..
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thanks for the site koritheman thats one I havent even seen before, I will definatly check it out!
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Quoting zebralove:
thank you koritheman I know so little yet that it is even hard to figure out where to look to find answers to my questions, I only knew 92 and 02 were el nino years because of a post earlier in the blog. I wish there was a really good page to look at for beginers to learn stuff. I am trying to learn it all in a very unorganized fashion it seems. Learning to read the charts, the lingo, the abreviations used, the basic formation and cloud types..... you name it I'm trying to learn it but it is really hard not even knowing really where to look. I thank everyone on WU who answers questions and helps point me in the right direction!!!


Perhaps this site will be of help:

http://www.theweatherprediction.com/
Member Since: March 7, 2007 Posts: 521 Comments: 19119
Quoting jipmg:


well the below average air get into Florida


Yes, we are going to have lows in the upper 80's, wohoo! Can hardly wait.
Member Since: March 10, 2006 Posts: 0 Comments: 9700
995. jipmg
Quoting IKE:
I think I see what the latest CMC is picking up on. Look at the 18Z GFS @ 168 hours and notice the low, inland, over Louisiana, in advance of the strong trough, cold front, moving into the SE USA. It'll probably wind up being a non-tropical low, but after that low moves through the SE USA, the cooler/colder air will be moving in....



well the below average air get into Florida
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994. JLPR
Quoting TexasHurricane:


old picture,check the one Ameister12 posted
that one is more recent
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About JeffMasters

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