Little change to 90L; new African tropical wave is worth watching

By: Dr. Jeff Masters , 8:53 PM GMT on July 30, 2010

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Invest 90L is a tropical wave in the eastern Atlantic near 10N 33W with a very limited amount of heavy thunderstorm activity but a decent amount of spin. It does not have a well-defined surface circulation, and has shown little change in organization today. CIMMS wind-shear analyses show a low amount of wind shear (5 - 10 knots) over 90L, and sea surface temperatures are a record warm 29°C. The wave currently is in a moist environment and is not being affected by the dry Saharan Air Layer (SAL) to its northwest. The disturbance has moved far enough away from the Equator to leverage the Earth's spin to help it develop. The Saharan Air Layer with its dust and dry air lurks just to the north of 90L, but the SHIPS model predicts 90L will remain far enough from the dry air over the next five days so that it will not interfere with development.


Figure 1. Afternoon visible satellite image from 2pm EDT 7/30/10 of the relatively tiny 90L, and the large new tropical wave that moved off the coast of Africa yesterday.

Forecast for 90L
One factor inhibiting development of 90L this week will be the Madden-Julian Oscillation (MJO.) The MJO currently favors downward motion over the tropical Atlantic, which will act to decrease the chances of tropical storm formation. The Madden-Julian oscillation is a pattern of enhanced rainfall that travels along the Equator from west to east. The pattern has a wet phase with large-scale rising air and enhanced thunderstorm activity, followed by a dry phase with large-scale sinking air and suppressed thunderstorm activity. Each cycle lasts approximately 30 - 60 days. When the Madden-Julian oscillation is in its wet phase over a hurricane-prone region, the chances for tropical storm activity are greatly increased.

Perhaps the main factor interfering with 90L's development will be the presence of the large tropical wave to the east of 90L that moved off the coast of Africa yesterday. This new wave is large enough and close enough to 90L that it will probably begin to dominate regional weather patterns this weekend, stealing away 90L's inflow of low-level moist air. The new wave may also act to bring sinking air over 90L that will tend to suppress 90L's thunderstorm activity. It may turn out that the new wave will also steal some of 90L's spin, and end up being a threat to develop itself later on this weekend.

The latest 8am EDT (12Z) model runs for 90L show very little in the way of development of the storm. The predominant track forecast takes 90L into or just north of the northern Lesser Antilles Islands about 6 - 8 days from now. Looking at climatology based on research done by Dr. Bob Hart at Florida State University,, 90L has a 19% chance of developing into a tropical cyclone by 2pm Sunday. NHC is putting these odds at 20%. Dr. Hart also has an experimental product showing that historically, about 30% of all tropical cyclones that develop at 90L's current position eventually hit land as a hurricane. Of course, 90L is not yet a tropical cyclone, and I think that the large tropical wave off the coast of Africa will kill 90L this weekend.

Tropical wave in the eastern Caribbean
A tropical wave in the eastern Caribbean, south of the Dominican Republic, is moving west at 15 - 20 mph with no signs of development. The wave is under a high 20 knots of wind shear, due to strong upper-level westerly winds from an upper level low centered north of Puerto Rico. This shear is expected to remain remain high through Saturday. By Sunday, when the wave will be approaching Nicaragua, the wave will be far enough away from the upper level low that shear should fall to the moderate range, 10 - 20 knots. Some development is possible on Sunday, but the wave will have only about a 1-day window to develop before its westerly motion brings it inland over Nicaragua on Monday. NHC is giving this wave a 10% chance of developing into a tropical depression by 2pm Sunday.

Extreme cold records for 2010
In my post yesterday, I reported that fourteen countries had set their all-time hottest temperature record this year. I neglected to mention that one country has also set its coldest temperature in recorded history mark in 2010. Guinea had its coldest temperature in its history on January 9, 2010, when the mercury hit 1.4°C (34.5°F) at Mali-ville in the Labe region. Of the 229 countries with extreme coldest temperature records, 14 of these records have occurred in the past ten years (6% of all countries). There have been five times as many (74) extreme hottest temperature records in the past ten years (33% of all countries.) My source for extreme weather records is Chris Burt, author of Extreme Weather.

New study finds huge drop in the plants that form the base of the oceanic food chain
A study published this week in the journal Nature documents that microscopic marine phytoplankton, which form the basis of the marine food chain, have declined by 40% globally since 1950. Joe Romm at climateprogress.org discusses the implications, using this headline:

Scientists may have found the most devastating impact yet of human-caused global warming — a 40% decline in phytoplankton since 1950 linked to the rise in ocean sea surface temperatures. If confirmed, it may represent the single most important finding of the year in climate science.

I plan to discuss this paper next week.

Next update
I'll have an update this weekend, probably by 8pm EDT Saturday.

Jeff Masters

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Poll time!

Q: In your opinion, what is the strongest Invest 90L will become in its lifetime.

A. It wont develop

B. Tropical Depression

C. Tropical Storm

D. Hurricane and/or Major Hurricane

No other letters, numbers, or symbols!!!
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It's really funny. If sea ice wasn't doing as well as it is now, with ice leveling off, the alarmists would be all over it, yet they're completely silent. Haven't mentioned a thing about it. Instead, they're trying to pull apart the credibility of Anthony Watts, which is failing quite substantially.
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Quoting Tazmanian:
if the 00z not runing on 90L


then may 90L has been drop


90L still on the NAVY site...
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Quoting SouthALWX:

http://www.ametsoc.org/memdir/seallist/get_listoftv.cfm

Is this not a legit list?


Don't waste your time. These folks use a help desk for responses. Just sayin, same song, no answers. Skip, Skip, Skip... Being skeptical is a fundamental priciple of any scientific process. Things are far from settled ;)

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Quoting StSimonsIslandGAGuy:


He holds a "seal of approval" but is not AMS certified.

Here is the list of certified broadcast meteorologists. His name is not there.


Took me about 10 seconds doing a google search to find this:

http://www.climateinstitute.org.au/index.php?option=com_content&view=article&id=681:be-sceptical-of -climate-sceptics&catid=112:

Scroll down and you will see that StSimons is absolutely correct. Also lists some other interesting tidbits.
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Quoting Chicklit:

Dr. Masters has suggested that may happen.
Not seeing organization in 90L at present.
Please correct me if I'm wrong.


No. You're right. It's not organizing. It's actually dying.
Member Since: March 7, 2007 Posts: 602 Comments: 21231
Don't know if this helps.
Quoting SouthALWX:

http://www.ametsoc.org/memdir/seallist/get_listoftv.cfm

Is this not a legit list?
Watts grew up around Cincinnati, Ohio and reportedly attended Purdue University[1], studying Electrical Engineering and Meteorology.[2]. Watts's "About" page mentions neither his Purdue attendance nor whether he graduated. [3]. Watts has not been willing to say whether he graduated.[4]

"Anthony began his broadcasting career, in 1978 in Lafayette, Indiana."[5]

Credentials

Credentials held

Watts holds an American Meteorological Society Seal of Approval (a discontinued credential that does not require a bachelor's or higher degree in atmospheric science or meteorology from an accredited college/university)[6] with a status of "retired".[7]

Credentials not held

Some online lists incorrectly refer to Watts as "AMS Certified"[8], but this is incorrect; the American Meteorological Society reserves its "AMS Certified" designation for its Certified Broadcast Meteorologists and Certified Consulting Meteorologists[9], and Watts posesses neither certification.[10],[11]
Member Since: October 9, 2008 Posts: 0 Comments: 8436
632. JLPR2
Quoting KoritheMan:


I can't tell if you're being sarcastic or serious. I'll assume the latter. If it's the former, forgive me.

1998 wasn't a "slightly above average season". The average amount of storms in a given season is 10. 1998 had 14. The average amount of hurricanes in a given season is 6. 1998 had 10, which most season have not rivaled or exceeded.

As for the US landfalls being "minor", that wasn't true for Georges.

Not to mention the four simultaneous hurricanes that existed on September 25: Georges, Ivan, Jeanne, and Karl. That was the first such occurrence since 1893.


Thank you, you took the words right out of my mouth. :D

Also, hello everyone!
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I'm not going to debate 90L dying and whether it should be 91L once wave takes over. That is not important. It's if combined anything develops.
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Hi Tankhead. It appears to be stretching east to west, not north to south... Just not convinced 90L is gaining. It appears to be losing at this point.
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if the 00z not runing on 90L


then may 90L has been drop
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Quoting SouthALWX:

http://www.ametsoc.org/memdir/seallist/get_listoftv.cfm

Is this not a legit list?



That must be another Anthony Watts, or that is a faked list!!! Just saving you the trouble SSI!!!
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Quoting TankHead93:
No I do not, but it is supposed to interact with the vigorous tropical wave behind it, which may revive it. Revive meaning that the wave behind 90L takes over and becomes the next area with high potential for development.


The wave and the invest will combine together, and Invest 90L will cease to exist, and 91L will be born.
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Quoting StSimonsIslandGAGuy:


It's not slander when it's true. Anthony Watts flunked out end of his sophomore year. He never got a degree anywhere. And he used to claim AMS certification until he was busted for not having it.



# Oral communication of false statements injurious to a person's reputation.
# A false and malicious statement or report about someone.

And so far, the report is STILL unproven...
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did they not run 00z models for 90L?
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Quoting KoritheMan:


Because the tropical wave to the east is taking over?

Dr. Masters has suggested that may happen.
Not seeing organization in 90L at present.
Please correct me if I'm wrong.
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Quoting Chicklit:



shortwaveloop

What I am looking for in the above 90L floater link is circulation. I don't see any.
Link Check out this link...
Member Since: August 12, 2009 Posts: 0 Comments: 203
Quoting JFLORIDA:




Pacific Decadal Oscillation index (blue, University of Washington) versus Global Temperature Anomaly (Red - GISS Temp). Smoothed data (thicker blue and red lines) and trend lines (thick straight line) are added.


While PDO does have some degree of correlation with short term variations in global temperature, the striking feature of Figure 3 is the contrast in trends between PDO and global temperature. Obviously the PDO as an oscillation between positive and negative values shows no long term trend. In contrast, temperature displays a long term warming trend. When the PDO last switched to a cool phase, global temperatures were about 0.4C cooler than currently.


..........................................

How did you measure the PDO accurately without guessing the temperature, because of surrounding weather stations, and how the heck were you measuring Global Temperatures since the turn of the 20th century, accurately. That would be like giving me made up data for the Arctic basin, and me accepting it. The graph is also adjusted 6 degrees. According to weather stations, and not the whole global temperature, the 1930s were the warmest years ever recorded. Right at the end of the warm PDO. Funny.

http://wattsupwiththat.com/2010/07/23/gistemp-movie-matinees/

http://www.youtube.com/watch?v=oNI_devHg7w&feature=player_embedded

Very tricky. The adjusted data appears quite nicely in these two images.

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Quoting KerryInNOLA:
1998 wasn't THAT MUCH of a blockbuster year. 4 ts and 3 minor and NO major CONUS hits and 14 total storms. A slightly above average season.


I can't tell if you're being sarcastic or serious. I'll assume the latter. If it's the former, forgive me.

1998 wasn't a "slightly above average season". The average amount of storms in a given season is 10. 1998 had 14. The average amount of hurricanes in a given season is 6. 1998 had 10, which most season have not rivaled or exceeded.

As for the US landfalls being "minor", that wasn't true for Georges.

Not to mention the four simultaneous hurricanes that existed on September 25: Georges, Ivan, Jeanne, and Karl. That was the first such occurrence since 1893.
Member Since: March 7, 2007 Posts: 602 Comments: 21231
Quoting SouthALWX:

http://www.ametsoc.org/memdir/seallist/get_listoftv.cfm

Is this not a legit list?



StSimon! Rebuttal?
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Quoting TankHead93:
Why the hell are people saying RIP to 90L? Doesn't make a lick of sense! (Annoyed flag on)


Because the tropical wave to the east is taking over?
Member Since: March 7, 2007 Posts: 602 Comments: 21231
Quoting Snowlover123:


Do you think that 90L looks healthy?
No I do not, but it is supposed to interact with the vigorous tropical wave behind it, which may revive it. Revive meaning that the wave behind 90L takes over and becomes the next area with high potential for development.
Member Since: August 12, 2009 Posts: 0 Comments: 203
Quoting TankHead93:
Why the hell are people saying RIP to 90L? Doesn't make a lick of sense! (Annoyed flag on)



shortwaveloop

What I am looking for in the above 90L floater link is circulation. I don't see any.

irloop
Don't see it here either.
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Quoting StSimonsIslandGAGuy:


It's not slander when it's true. Anthony Watts flunked out end of his sophomore year. He never got a degree anywhere. And he used to claim AMS certification until he was busted for not having it.


http://www.ametsoc.org/memdir/seallist/get_listoftv.cfm

Is this not a legit list?
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Quoting TankHead93:
Why the hell are people saying RIP to 90L? Doesn't make a lick of sense! (Annoyed flag on)


Do you think that 90L looks healthy?
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Quoting StSimonsIslandGAGuy:


It's not slander when it's true. Anthony Watts flunked out end of his sophomore year. He never got a degree anywhere. And he used to claim AMS certification until he was busted for not having it.



I am a real skeptic of everything! ;) Source?
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Why the hell are people saying RIP to 90L? Doesn't make a lick of sense! (Annoyed flag on)
Member Since: August 12, 2009 Posts: 0 Comments: 203
Quoting StSimonsIslandGAGuy:


Actually a majority of years one or more Florida stations reports snow.


I wouldn't say that. Legit snow is rare, flurries and sleet as an example are more common.
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I found this interesting and just published. If you can, I would check it out. I cannot share it, aside from the abstract, sorry. I know some of the lurkers have access :)

GEOPHYSICAL RESEARCH LETTERS, VOL. 37, L14605, 6 PP., 2010
doi:10.1029/2010GL043572

Pacific Decadal Oscillation documented in a coral record of North Pacific winter temperature since 1873
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Quoting Snowlover123:


Your source?


Well, I've lived here on and off for the past 31 years...but I know what you mean. ;-) You can check here for an easy-to-read summary of most recent snow events, all of them properly sourced...but I can tell you that it snowed in '03, '04, '06, '07, twice in '08, and three times in early '10. (It even spat a few flakes here in Naples; I saw it with my own eyes.)
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Woo! Blog update! Let me know your thoughts...

http://www.wunderground.com/blog/jeffs713/comment.html?entrynum=11
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You can save your F5 key and sacrifice your mouse. Works well when your in the dark like I am most of the time. How many of you have 5+ windows open checking the tropics before they post? Get in the game. Go Titans and VY.
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Quoting StSimonsIslandGAGuy:


I'll leave it to you to find proof contradicting me. ;)


So YOUR slander of a person requires ME to prove you wrong?

wow...
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Quoting StormW:
Good night everyone!
Night Elder Chief
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Quoting clwstmchasr:


I think he has answered that question about 100 times already.


I see you quoted a troll. Please ignore the troll.
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Quoting StormW:
Good night everyone!

I read your update earlier today, thanks. Have a great evening, the blog needs a "time out" tonight :o)
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Quoting StormW:
Good night everyone!
Good night Storm. Hope all is well with you. Thanks for all the updates you give.
Member Since: October 9, 2008 Posts: 0 Comments: 8436
Quoting StSimonsIslandGAGuy:


Actually a majority of years one or more Florida stations reports snow.
Snow is rare in South Florida.
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Quoting Snowlover123:


Look at Bordonaro's pics of snow. He even says that they're a rare event.

Snow average is 2.5" a winter in the Dallas-Ft Worth, TX area.. Usually a little sleet and a snow flurry or two..

This winter, we had almost 18" of snow, very very rare!! Including a real White Christmas!!
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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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