CSU and TSR predict an extremely active 2011 Atlantic hurricane season

By: Dr. Jeff Masters , 12:54 PM GMT on December 09, 2010

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A continuation of the pattern of much above-average Atlantic hurricane activity we've seen since 1995 is on tap for 2011, according to the latest seasonal forecast issued Wednesday by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). They are calling for 17 named storms, 9 hurricanes, and 5 intense hurricanes. An average season has 10 - 11 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast is a very aggressive one, since only six seasons since 1851 have had as many as 17 named storms; 19 seasons have had 9 or more hurricanes. The 2011 forecast calls for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (49% chance, 31% chance is average) and the Gulf Coast (48% chance, 30% chance is average). The Caribbean is forecast to have a 62% chance of seeing at least one major hurricane (42% is average.) Five years with similar pre-season November atmospheric and oceanic conditions were selected as "analogue" years that the 2011 hurricane season may resemble: 2008, 1999, 1989, 1961, and 1956. The average activity for these years was 12 named storms, 7 hurricanes, and 4 major hurricanes.

The forecasters cited several reasons for their forecast of a much above-average season:

1) Unusually warm sea surface temperatures continue in the tropical Atlantic this fall, an indication that the active hurricane period we have been in since 1995 will continue (in technical terms, the positive phase of the Atlantic Multidecadal Oscillation, AMO, will continue.) SSTs in Atlantic Main Development Region (MDR) for hurricanes, from the Caribbean eastwards to the coast of Africa, were at a record high in October (November data are not yet available.)

2) Hurricane activity in the Atlantic is lowest during El Niño years and highest during La Niña or neutral years. This occurs because El Niño events tend to increase westerly upper-level winds over the tropical Atlantic, bringing high wind shear harmful for hurricanes. The CSU team notes that we are currently experiencing moderate to strong La Niña conditions, with an unusual amount of cool water present in the top 300 meters of the Equatorial Pacific Ocean off the coast of South America. Since 1979, only eight years have had similar amounts of cool water in November. The hurricane seasons that followed each of those eight years were unable to transition to El Niño conditions. Thus, the CSU team expects that we will have neutral or La Niña conditions in place for the Atlantic hurricane season of 2011, which should act to keep wind shear values average to below average, enhancing hurricane activity. Of the 16 El Niño/La Niña computer models that made November predictions for the July-August-September 2011 portion of hurricane season (Figure 1), only 4 (25%) predicted that El Niño would arrive.

How accurate are the December forecasts?
The CSU real-time December forecasts did not shown any skill over the period 1992 - 2007, so the forecast scheme was overhauled and a new scheme implemented for the forecasts made for the 2008 - 2010 hurricane seasons. This new scheme showed some decent skill in those three years, with skill levels 18%, 10%, and 30% above chance for predicting the number of named storms, hurricanes, and intense hurricanes, respectively. Still, three years is too short of a time period to evaluate the skill of these December forecasts, and we should view the latest forecast as an experimental research product. Last year's December forecast for the 2010 hurricane season predicted 13.5 named storms, 7 hurricanes, and 4 intense hurricanes. The actual numbers were 19 named storms, 12 hurricanes, and 5 intense hurricanes.


Figure 1. Forecasts of El Niño conditions by 20 computer models, made in November 2010. The longest range forecasts for July-August-September (JAS) at the right side of the image show that 4 models predict weak El Niño conditions, 7 predict neutral conditions, and 5 predict a weak to moderate La Niña. El Niño conditions are defined as occurring when sea surface temperatures in the Equatorial Pacific off the coast of South America (the "Niño 3.4 region) rise to 0.5°C above average (top red line). La Niña conditions occur when SSTs in this region fall to 0.5°C below average. Image credit: Columbia University.

2011 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.
The British private forecasting firm Tropical Storm Risk, Inc. (TSR), issued their 2011 Atlantic hurricane season forecast on Monday. They are also calling for a very active year: 15.6 named storms, 8.4 hurricanes, and 4 intense hurricanes. TSR predicts a 66% chance of an above-average hurricane season, 22% chance of a near-normal season, and only a 12% chance of a below normal season. TSR bases their December forecast on predictions that sea surface temperatures next fall in the tropical Atlantic will be above about 0.3°C above average, and trade wind speeds will be about 0.7 m/s slower than average. The trade wind speed prediction is based on a forecast for a weak La Niña in August-September 2011.

I like how TSR puts their skill level right next to the forecast numbers: 2% skill above chance at forecasting the number of named storms, 1% skill for hurricanes, and 7% skill for intense hurricanes. That's not much skill, and really, we have to wait until the June 1 forecasts by CSU, NOAA, and TSR to get a forecast with reasonable skill.

Comparing 2005 and 2010 steering currents
The U.S. got extremely fortunate during the 2010 hurricane season that the steering currents carried most of the storms out to sea, or forced them to the south. A very graphic way of looking at this is to compare the amount of rain that fell due to tropical cyclones in the Atlantic in 2005 versus 2010 (Figure 2.) The U.S. received a direct hit only from Tropical Storm Bonnie, which hit South Florida as a minimal 40 mph tropical storm and caused no significant damage. TSR is predicting that this luck will not hold in 2010; they project that five named storms will hit the U.S., with two of these being hurricanes.


Figure 2. Rainfall amounts due to all Atlantic tropical cyclones in 2005 and 2010, as measured by NASA's TRMM satellite. Steering currents in 2010 tended to recurve many storms out to sea between the Caribbean and Bermuda, due to a large number of unusually strong troughs of low pressure moving off the U.S. East Coast.

Weekend winter storm for Eastern U.S.
The latest 06Z (1am EST) set of computer model forecasts for this weekend's winter storm over the Midwest and Eastern U.S. point towards a more northerly path for the storm, bringing the axis of heaviest snow through Wisconsin and Michigan. There is still a great deal of uncertainty in the predicted timing and strength of the storm, but a renewed blast of cold air Monday and Tuesday over the Southeast U.S. is still highly likely in the wake of the storm.

Jeff Masters

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Looks like we might have another setup thru 15 thru the 17th.. From the Models i've been looking at.. But not as cold but have to c in a few days if it changes.. anyone c this?

Member Since: August 15, 2008 Posts: 0 Comments: 2133
Quoting doorman79:


Hey Atmo! How is life Abita way?

As far as the weather, would be great if I were hunting, but have you ever hit your thumb with a hammer when its 30f lol. :)
Greetings.

Yeah, hammer, thumb, cold...that's loads of phun.
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Quoting KerryInNOLA:
Bull! WU member Quadrantid is zeroing in on Earth like planets.Bob Lazar says we almost have reverse engineered that space saucer they have at area 51.

I predict that in about 20 years those of us with connections or wealth will be able to "colonize" planets of astounding beauty and totally pristine with docile creatures that we can domesticate. All forms of pleasure will be legal and there will evolve a true Utopian society for those lucky enough to go.


That sounds good in a Kirk kind of way. He took forms of pleasure to new heights. As long as I get my share of docile creatures to "domesticate" there won't be any problems. :)
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Quoting atmoaggie:
Hehe, I knew that but wasn't going to say anything. ;-)


Hey Atmo! How is life Abita way?

As far as the weather, would be great if I were hunting, but have you ever hit your thumb with a hammer when its 30f lol. :)
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Quoting DoverWxwatchter:
I never said you didn't know what theory meant.  You come across as a smart young man.  I enjoy your posts.



Sorry about that, I thought you were directing that towards me, but yeah, no hard thoughts
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Quoting KerryInNOLA:
Bull! WU member Quadrantid is zeroing in on Earth like planets.Bob Lazar says we almost have reverse engineered that space saucer they have at area 51.

I predict that in about 20 years those of us with connections or wealth will be able to "colonize" planets of astounding beauty and totally pristine with docile creatures that we can domesticate. All forms of pleasure will be legal and there will evolve a true Utopian society for those lucky enough to go.


Sssssssssshhhhhhh. No one else was suppose to know that and now its on the internet. Ticket prices will soar!
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Quoting caneswatch:


As long as there are no talks about GW....lol


Keep it under a buck, and we'll be good LOL
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Quoting Some1Has2BtheRookie:


That would cost more than a penny. That would up the ante' some.



LOL!
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Possible that station's temps calibrated a little low...



Already showing lower that our forecast low. (31 F)

On second look, Slidell recorded a 31 (30 minutes ago) when the forecast low there was 32 (~20 miles east of me). Maybe it's right!
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Loving this weather. (In SE LA).

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Quoting caneswatch:


As long as there are no talks about GW....lol


That would cost more than a penny. That would up the ante' some.
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Quoting PSLFLCaneVet:


Awwww, come on, in for a penny.....


As long as there are no talks about GW....lol
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Quoting BahaHurican:
Search ResultsAnswers.com - What is the singular form of species
Grammar question: What is the singular form of species? Species can be both singular or plural.
Hehe, I knew that but wasn't going to say anything. ;-)
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The latest space shuttle problems are crazy. Now they are saying that if the tanking test fails they might have to scrub the whole thing and roll it back in.
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Search ResultsAnswers.com - What is the singular form of species
Grammar question: What is the singular form of species? Species can be both singular or plural.
Member Since: October 25, 2005 Posts: 19 Comments: 22322
Hey, Oss!

I completely missed that somehow the whole post didn't take. (maybe I deleted the last part on accident before "Post"?)
Quoting atmoaggie:
A lot of theory never is actually witnessed, either.

Take a look at the theoretical maximum potential intensity for hurricanes, for example. We never do actually see a system achieve it.

Or the theoretical efficiency of an engine. Or what theory says for network bandwidth, down the wire level. Or what the temperature should be tonight, in theory. (We do okay at that last one, because of all of our statistical data that shows that ways in which the theory misses on reality)

And some theories' symptoms are obvious, but not the causes or the sensitivities to slight changes in the causes, such as gravity.

As Jedkins, I have a formal education in the earth sciences and all I see in climate change is a new area of study that is not well understood, yet. So very much of the theory is based on untested physical equations that were built around the slightest bit of data and a large amount of assumption.


Addendum:
And climate reality? We don't even know our current climate all that well, much less delta-climate, or worse, delta-climate/delta-time. (some will be scratching their heads...)
;-)
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11 will probably be another dumb trough year
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Quoting caneswatch:


Haha, i'm not gonna stay on for the weird stuff.


Awwww, come on, in for a penny.....
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Quoting pilotguy1:


We need to colonize space to survive as a specie.


You are correct, sir. Doing so now is not an option.
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Quoting PSLFLCaneVet:


Winks. No half measures. In or out.... lol


Haha, i'm not gonna stay on for the weird stuff.
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http://www.youtube.com/watch?v=SKRma7PDW10

Here is my two cents! I hope this makes yall smile.
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Quoting PSLFLCaneVet:


LMAO. Yep, that takes the cake, so far. Miles to go, friend.

Inanity, puts you in the finals, for correctly used WOTD. Kudos.


ty
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Quoting PensacolaDoug:
AGW! I'm not involved...First time for everthing!


LOL, me either, but our taxable footprint is :)



L8R >>>
Member Since: June 12, 2005 Posts: 6 Comments: 8186
Quoting DontAnnoyMe:
Good evening.



And the inanity that goes with it.



Misused word of the day. Congrats!



LMAO. Yep, that takes the cake, so far. Miles to go, friend.

Inanity, puts you in the finals, for correctly used WOTD. Kudos.
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AGW! I'm not involved...First time for everthing!
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Just a question also, why did the glaciers that created the Great Lakes go away?

Additionally, relating to some of the comments on ice cores, are we subject to human interpretation/interpolation with respect to DNA in ice cores? Can they be homogenized :)

Greenland Ice Core Analysis Shows Drastic Climate Change Near End Of Last Ice Age

Bugs in Greenland?

Oldest Known DNA Found in Greenland Ice Core


Think about it !
Member Since: June 12, 2005 Posts: 6 Comments: 8186
Quoting caneswatch:
Is it safe to come in here?


Winks. No half measures. In or out.... lol
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Is it safe to come in here?
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“We’ve never seen it like this before; it just keeps on coming,” farmer Philippa McGaw said on Thursday after her Crookwell, New South Wales, property received 150 millimetres in 18 hours.

Australia battles worst floods in decades
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Quoting pilotguy1:
What is the "ideal" temperature of the Earth?


How is everyone doing tonight?

Pilotguy1, to answer your question, the "ideal" temperature for the Earth is the temperature that will support the largest diversity of life. With, or without, man's involvement in the natural cycle of the Earth's ever changing climate there are windows of time that best supports this scenario. There has been and will be times that Earth's climate supports minimal diversity of life. This should not deflect from the fact that the Earth is warming now and faster than in the past cycles without any major climate changing natural events. This would include major volcanic events and impacts from space, for examples. Should man have the technology to use to attempt to achieve the most desirable climate for the greatest diversity of life on Earth then I consider it in man's best interest to do so. Anything else would seem foolish, to me.

JMO
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I just keep reading and we still have a ways to go before we really know :)

A Determination of the Cloud
Feedback from Climate Variations
over the Past Decade
A. E. Dessler


with respect to some earlier posts

Greenland ice sheet flow driven by short-term weather extremes, not gradual warming: UBC research

and a bonus :)

'Greener' Climate Prediction Shows Plants Slow Warming ~~ NASA

Member Since: June 12, 2005 Posts: 6 Comments: 8186
The Panama Canal has reopened after heavy rains and flooding that swelled nearby lakes forced the iconic waterway to close. The canal was closed so floodgates for two lakes could be opened and relieve the pressure. Eight people have died in the heaviest rain Panama has seen in 73 years since records have been kept.

http://news.yahoo.com/s/ac/20101209/tr_ac/7371208_panama_canal_reopens_for_traffic_after_historic_f looding
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For West Palm Beach

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Quoting Floodman:
atmoaggie, you are a calming, reasonable influence here...perhaps you're in the wroing room? LOL

You speak the truth...an internal combustion engine gets a tiny fraction of it's theoretical energy from it's fuel...maybe a better way to say it is "potential"?
Sure ;-)

When the "seas will boil" crew are out to play, I just cannot help myself.
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Quoting ColoradoBob1:
Just an FYI -
Earlier today there were 11 stations in Greenland reporting precipitation , 7 of them were reporting rain.
Currently :
Qaqortoq 51.0 °F Light Rain

http://www.wunderground.com/global/GL.html

11/16/2010 – The overall warming of the earth's northern half could result in cold winters. The shrinking of sea-ice in the eastern Arctic causes some regional heating of the lower levels of air – which may lead to strong anomalies in atmospheric airstreams, triggering an overall cooling of the northern continents, a study recently published in the Journal of Geophysical Research shows. “These anomalies could triple the probability of cold winter extremes in Europe and northern Asia,” says Vladimir Petoukhov, lead author of the study and climate scientist at the Potsdam Institute for Climate Impact Research. “Recent severe winters like last year’s or the one of 2005-06 do not conflict with the global warming picture, but rather supplement it.”

http://www.pik-potsdam.de/news/press-releases/global-warming-could-cool-down-temperatures-in-winter ?set_language=en
Good idea, let's get back to weather. Oh...nevermind.
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Quoting Neapolitan:

Laugh if you wish, but my confidence is born of the knowledge that there exists vastly more evidence supporting the theory than exists refuting it. Now, aside from ridicule, one-liners, and endless recitations of oft-debunked "counter-proof", what, really, does the other side have?

And with that, I am out again until morning. G'night, all...
??? None of it exists.

Here is an example of our AGW data, to date.
Trend data of my AC in my house doesn't exist, either. But I'm not about to assume that I have windows open all summer just because it runs longer when I start measuring it's on/off cycles this year. I'll assume that my 12 year old unit just loses efficiency over time. But other possible causes would be investigated before I just off and buy a new compressor, I assure you.

Is it possible that a window is open? Of course. Is it possible that one or another component isn't operating the same as it once was? Of course. Is it possible that there is an anthropogenic blockage of the air intake by my kid's in-house tent? Of course.

The cause...well, if one simply assumes any one of the above possibilities is true, they rule out the rest without actually checking them. This is exactly the state of the AGW evidence. Other possibilities haven't even been thought of, nor checked as we haven't measured anything long enough nor well enough to rule out anything else.

And we'll not have good evidence of anything, either way, for decades, at least.
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I am out as well...dinner beckons...
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Just an FYI -
Earlier today there were 11 stations in Greenland reporting precipitation , 7 of them were reporting rain.
Currently :
Qaqortoq 51.0 °F Light Rain

http://www.wunderground.com/global/GL.html

11/16/2010 – The overall warming of the earth's northern half could result in cold winters. The shrinking of sea-ice in the eastern Arctic causes some regional heating of the lower levels of air – which may lead to strong anomalies in atmospheric airstreams, triggering an overall cooling of the northern continents, a study recently published in the Journal of Geophysical Research shows. “These anomalies could triple the probability of cold winter extremes in Europe and northern Asia,” says Vladimir Petoukhov, lead author of the study and climate scientist at the Potsdam Institute for Climate Impact Research. “Recent severe winters like last year’s or the one of 2005-06 do not conflict with the global warming picture, but rather supplement it.”

http://www.pik-potsdam.de/news/press-releases/global-warming-could-cool-down-temperatures-in-winter ?set_language=en
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Well, I gotta head out also... maybe by the end of next week I'll be able to legitimately have a few days off to loll around the blog and rip Klotzbach and Gray to shreds... lol

Meanwhile, who is this McBill character??? Sure hope u can handle the "heat" when the 2011 season gets going, dude.... sounds like u might add some spice to the tropical wx discussion next year.... lol

Later....
Member Since: October 25, 2005 Posts: 19 Comments: 22322
Quoting NRAamy:
but Jerry, you're a peace loving Hippie.....

:)


Even a peace loving hippie likes a good row now and then...see how the other half lives, as it were...LOL
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Now, aside from ridicule, one-liners, and endless recitations of oft-debunked "counter-proof", what, really, does the other side have?



answer:

SQUAWK!!!!!!


;)
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Quoting Neapolitan:

I agree with you. And so far as AGW theory is concerned, there are piles of "hard, non-circumstantial evidence" to bolster it--the reason my initial skepticism morphed into support many years ago, and continues to solidify each day and with every new piece of evidence.
In your opinion.

In my opinion, the evidence supporting that man has had a significant part in detected trends (except that polluted by UHI) and that modeled climate of the future is all circumstantial.

I suppose it is fickle enough that one can still be left to their own interpretations...of which no one here will change of anyone else.
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Quoting atmoaggie:
Hook, sinker, leader, cork, line, rod, reel, fisherman, boat, lake.

Laugh if you wish, but my confidence is born of the knowledge that there exists vastly more evidence supporting the theory than exists refuting it. Now, aside from ridicule, one-liners, and endless recitations of oft-debunked "counter-proof", what, really, does the other side have?

And with that, I am out again until morning. G'night, all...
Member Since: November 8, 2009 Posts: 4 Comments: 13556
18Z models do not have an EC low anymore.. I still think the models are wrong and a low will form off the Midatlantic Coastline, heads NNE.. This results in rain changing over to snow for the big cities. The NAO is negative, something has to happen..
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BTW, McBill, having read the second paragraph of your post again, I don't think we r that far apart in our thinking.... my idea is that we need to consider how to deal w/ potential effects instead of arguing over what seems to be the likely effect. As example, in the Bible, it only took a 7-year famine to change the history of the Israeli/Jewish pple... so even a 50-year "blip" of climate change could have serious impacts on world affairs...
Member Since: October 25, 2005 Posts: 19 Comments: 22322

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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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