NOAA predicts an active Atlantic hurricane season: 15 named storms, 8 hurricanes

By: Dr. Jeff Masters , 4:08 PM GMT on May 19, 2011

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The National Oceanic and Atmospheric Administration (NOAA) issued its 2011 Atlantic hurricane season forecast today. NOAA forecasts a very active and possibly hyperactive season. They give a 65% chance of an above-normal season, a 25% chance of a near-normal season, and just a 10% chance of a below-normal season. NOAA predicts a 70% chance that there will be 12 - 18 named storms, 6 – 10 hurricanes, and 3 - 6 major hurricanes, with an Accumulated Cyclone Energy (ACE) 105% - 200% of the median. If we take the midpoint of these numbers, NOAA is calling for 15 named storms, 8 hurricanes, 4.5 major hurricanes, and an ACE index 152% of normal. A season with an ACE index over 165% is considered "hyperactive." An average season has 10 – 11 named storms, 6 hurricanes, and 2 intense hurricanes. Hurricane seasons during 1995-2010 have averaged about 15 named storms, 8 hurricanes, and 4 major hurricanes, with an ACE index 151% of the median. NOAA classifies 11 of the 16 seasons since 1995 as above normal, with eight being hyperactive. Only five seasons since 1995 have not been above normal, which include four El Niño years (1997, 2002, 2006, and 2009), and the 2007 season.

The forecasters cited the following main factors that will influence the coming season:

1) Above-average sea surface temperatures (SSTs) are expected in the hurricane Main Development Region (MDR), from the Caribbean to the coast of Africa between between 10°N and 20°N. SSTs in the MDR during April were about 0.5°C above average, the 14th warmest April SSTs in the past 100 years. This is far below last year's record 1.4°C anomaly, but still plenty warm enough to help drive above-average Atlantic hurricane activity. Long-range computer forecast models are predicting a continuation of these above-average SSTs through the peak part of hurricane season.

2) We are in an active period of hurricane activity that began in 1995, thanks to a natural decades-long cycle in hurricane activity called the Atlantic Multidecadal Oscillation (AMO): "During 1995-2010, some key aspects of the tropical multi-decadal signal within the MDR have included warmer than average SSTs, reduced vertical wind shear and weaker easterly trade winds, below-average sea-level pressure, and a configuration of the African easterly jet that is more conducive to hurricane development from tropical waves moving off the African coast. Many of these atmospheric features typically become evident during late April and May, as the atmosphere across the tropical Atlantic and Africa begins to transition into its summertime monsoon state."

3) An El Niño event is not expected this year: "Another climate factor known to significantly impact Atlantic hurricane activity is the El Niño-Southern Oscillation (ENSO.) The three phases of ENSO are El Niño, La Niña, and ENSO-Neutral. El Niño events tend to suppress Atlantic hurricane activity, while La Niña events tend to enhance it (Gray 1984). Currently, the 2010-11 La Niña episode is dissipating. Based on observations and ENSO forecast models, ENSO-Neutral conditions are likely during the 2011 Atlantic hurricane season."

4) NOAA is increasingly using output from ultra-long range runs of the computer forecast models we rely on to make day-to-day weather forecasts, for their seasonal hurricane forecasts: "The outlook also takes into account dynamical model predictions from the NOAA Climate Forecast System (CFS), the European Centre for Medium Range Weather Forecasting (ECMWF), the United Kingdom Meteorology (UKMET) office, and the EUROpean Seasonal to Inter-annual Prediction (EUROSIP) ensemble. These models are indicating a high likelihood of an above normal season."

How accurate are the NOAA seasonal hurricane forecasts?
A talk presented by NHC's Eric Blake at the 2010 29th Annual AMS Conference on Hurricanes and Tropical Meteorology studied the accuracy of NOAA's late May seasonal Atlantic hurricane forecasts, using the mid-point of the range given for the number of named storms, hurricanes, intense hurricanes, and ACE index. Over the past twelve years, a forecast made using climatology was in error, on average, by 3.6 named storms, 2.5 hurricanes, and 1.7 intense hurricanes. NOAA's May forecast was not significantly better than climatology for these quantities, with average errors of 3.5 named storms, 2.3 hurricanes, and 1.4 intense hurricanes. Only NOAA's May ACE forecast was significantly better than climatology, averaging 58 ACE units off, compared to the 74 for climatology. Using another way to measure skill, the Mean Squared Error, May NOAA forecasts for named storms, hurricanes, and intense hurricanes had a skill of between 5% and 21% over a climatology forecast (Figure 2). Not surprisingly, NOAA's August forecasts were much better than the May forecasts, and did significantly better than a climatology forecast.

Figure 1. Mean absolute error for the May and August NOAA seasonal hurricane forecasts (1999 - 2009 for May, 1998 - 2009 for August), and for forecasts made using climatology from the past five years. A forecast made using climatology was in error, on average, by 3.6 named storms, 2.5 hurricanes, and 1.7 intense hurricanes. NOAA's May forecast was not significantly better than climatology for these quantities, with average errors of 3.5 named storms, 2.3 hurricanes, and 1.4 intense hurricanes. Only NOAA's May ACE forecast was significantly better than climatology, averaging 58 ACE units off, compared to the 74 for climatology. Image credit: Verification of 12 years of NOAA seasonal hurricane forecasts, National Hurricane Center.

How do NOAA's seasonal hurricane forecasts compare to CSU and TSR?
Two other major seasonal hurricane forecasts will be released over the next two weeks. On June 1, Phil Klotzbach and Bill Gray of Colorado State University (CSU) issue their forecast, and the British firm Tropical Storm Risk (TSR) will issue their outlook on May 24. A three-way comparison of the forecast accuracy of the three groups' forecast (Figure 2) reveals that all three organizations enjoy some success at making accurate seasonal forecasts, with NOAA and CSU making the best late May/early June forecasts overall. While the skill of these forecasts is low, they are useful for businesses such as the insurance industry.

Figure 2. Comparison of the percent improvement over climatology for May and August seasonal hurricane forecasts for the Atlantic from NOAA, CSU and TSR from 1999-2009 (May) and 1998-2009 (August). using the Mean Squared Error. Image credit: Verification of 12 years of NOAA seasonal hurricane forecasts, National Hurricane Center.

Jeff Masters

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I am happy to hear there is a silver lining to the flooding; however, I am concerned about what is in the water and what will settle to the bottom and end up in the food chain.

The EPA should be out there in force right now testing the waters and anticipating problems, forcing business to take measures to prevent environmental disasters.
Something tells me they are not.

The 36 documented incidents of contamination further north due to flooding is ominous.
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Quoting Patrap:
..only 1.5 shopping days left till the Apocalypse.

Dang... and I still have people to shop for and I have to buy the dinner stuff...
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Predictions from the wackjob.

The rapture will occur on May 21, 2011 with approximately 3% of the population being called to heaven.[14]
Earthquakes will begin on May 21 on the Kiritimati Island (Christmas Island near Australia) at 6:00 pm CXT (11:00 am UTC).[14]
At least we have a blogger that can report live on the first signs of doomsday. LOL
Earthquakes will continue "as the sun advances" with New York to be affected at approximately at 6:00pm EDT (10:00 pm UTC).[14]
the end of the world as we know it will take place five months later on October 21, 2011

This is the offical responsce from NYPD

The New York Police Department(NYPD) stated: "We don't plan any additional coverage for the end of the world. Indeed, if it happens, fewer officers will be required for streets that presumably will be empty."

Happy Doomsday eve everyone
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447. HadesGodWyvern (Mod)
Japan Meteorological Agency
Tropical Cyclone Advisory #1
21:00 PM JST May 20 2011

SUBJECT: Tropical Depression Near Caroline Island

At 12:00 PM UTC, Tropical Depression (1004 hPa) located at 8.7N 140.8E has 10 minute sustained winds of 30 knots with gusts of 45 knots. The depression is reported as moving west slowly.

Dvorak Intensity: T2.0

Forecast And Intensity
24 HRS: 9.3N 138.0E - 35 knots (CAT 1/Tropical Storm)

From Tiyan Guam
A Tropical Storm Warning is in effect for Fais and Ulithi Islands in Yap
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While the Louisiana Department of Environmental Quality issued an emergency order [pdf] last week that addresses steps that should be taken by wastewater treatment systems and other potential pollution sources, it did not specifically address preparations by oil and chemical facilities and waste sites. LABB (Louisiana Bucket Brigade) is sending a letter today to relevant agencies requesting plans for soil and water sampling and cleanup in the event of spills.

The watchdog group is especially concerned about the thousands of oil waste pits like the one in Grand Bois. Officials with the Louisiana Department of Environmental Quality told LABB that they have ordered only three of the 4,000 such pits to be emptied in preparation for the flooding.

In response to concerns about flooding of oil waste pits on Louisiana's Bateman Island at the base of Atchafalaya Bay, the state Department of Natural Resources told KATC TV that the facility has a perimeter levee designed to keep out flood waters and that owner U.S. Liquids of Louisiana has recently begun work to raise the levee's height from 12.5 to 14 feet.

These pits have been causing problems in other states. Regulators in North Dakota say oil companies may have ignored warnings to protect the structures from spring floods, resulting in some three dozen spills in recent weeks. Nineteen companies now face millions of dollars in fines as a result.

LABB Director Anne Rolfes notes that regulatory agencies had no effective plans for dealing with widespread chemical pollution following Hurricane Katrina in 2005 -- including a million-gallon oil spill from the Murphy Oil Refinery in a residential community of St. Bernard Parish just east of New Orleans (photo above).

"Oil was everywhere - in the house, in the slab. It was unreal and we decided to move away," says Johnny Lewis, who lived nearby. "I got zero information from the refinery, zero from government who is supposed to be looking out for us."

LABB is holding a press conference in New Orleans today in hopes of prompting industry and the state to properly inform residents about the potential for chemical contamination in flood areas. Residents who witness spills and other contamination incidents can report them to the group's Chemical Accidents Crisis Map at

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Ahh, another sign of the rapture fast approaching, thanks Skyepony
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443. Skyepony (Mod)
Fiji's Meterological Service says a heavy swell generated by a high pressure system over the Tasman Sea was responsible for a giant wave which reached Sigatoka's highway. A Fiji Rugby team, which witnessed the wave hit, has told the Fiji Broadcasting Corporation it went right over their car and left fish and debris on the highway. Rajneel Prasad from the Fiji Meterological Service is urging people in Fiji to secure boats and other belongings and says more waves are expected at high tide. "It must have coincided with the high tide that was at 8am this morning, and we can expect similiar stuff to happen at around 9pm when the high tide comes back again and probably another one at 9am tomorrow morning when we have a two metre high tide," he said.
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..only 1.5 shopping days left till the Apocalypse.
Member Since: July 3, 2005 Posts: 437 Comments: 135399
When swollen Mississippi River subsides, crawfish will be easy pickins

ST. MARTINVILLE — Crawfisherman Bill Granger welcomes the muddy Mississippi River water shooting toward his perch on the Atchafalaya River.

To him, the water is a road, a home and a living. Granger, 43, would like to see a full river each year.

On Thursday afternoon, pulling his boat from its swelling banks at Bayou Benoit Landing in St. Martinville, he said the Mississippi River water coursing south is akin to an earlier time that he has heard about only through his grandfather’s tales.

“That was our roads, how we lived, how we moved,” Granger said.

While he still calls the Atchafalaya River’s passageways his “brick roads,” the waterway Granger spends more time on than at home is rarely the river he longs for, the one his grandfather said roamed freely, its breadth spreading to form a plentiful, water world.

For perhaps the next month, as the Mississippi water flows through the Morganza Floodway, the Atchafalaya finally will meet Granger’s idealized image.

Yet during the river’s zenith, crawfishers aren’t expected to have much luck at their trade.

Scientists say that because of treacherous currents, flooded boat landing docks and the fact that the crawfish will disperse throughout the water, making them difficult to trap, critter hunting will soon become an arduous affair.

Already crawfish trappers throughout the St. Martinville area say docking is getting more difficult and that soon levees will become the only possible docking grounds, something most avoid because boats can damage levees, especially when they become damp.

Returning to Sandy Cove Landing, several miles south of the Benoit dock, Mark Bonin, 42, recalled watching his crawfish-trapping father launch his boat straight from the levee during the 1973 flood.

The Sandy Cove dock is now under water. And the 300-yard-long road leading from the levee to that dock now resembles a bayou.

But after the Morganza floodgates shut and the river subsides, crawfish will be everywhere. Crawfish trappers and laymen alike who lived through the 1973 flood recall simply picking them off the levees.

Their abundance largely will be due to the added oxygen in the waterway after decomposing vegetation has been flushed out, said Robert Romaire, a Louisiana State University AgCenter professor who studies crawfish management.

Randy Bourque, 34, already noticed a difference while out in the river Thursday morning. He was out to extend the lines on his traps to accommodate the rising tide.

“During Easter, the Holy Week, it was like a sewage pit out there, smelling, completely black,” Bourque said. “Now everything’s clean, and them crawfish is shedding and getting pretty.”

Higher oxygen levels will keep much more crawfish alive longer than during a typical year, and as more water is expected to remain in the river for longer, the crustaceans also will have much longer to grow, according to Romaire.

While Romaire anticipates a possible wild crawfish season extending as late as August — typically it ends in June — Bourque dreams, “Man, I hope we can fish the whole year.”

James Richard, 57, recalled the crawfish cornucopia of 1973.

“The crawfish ran in ‘73. Everywhere you put a trap, you got filled up,” he said.

Yet Jay Huner, 65, a marine scientist and former director of the University of Louisiana at Lafayette Crawfish Research Center, recalled a darker side to that flood.

“You literally could not give away crawfish because there were so many,” he said.

He warned that this year could be the same, “that there is so much crawfish that no one can access it.” In other words, flooding the market with too much crawfish could drop the price below what crawfish trappers need to survive, thereby not making it worth their while to catch the critters.

Another negative to the 1973 flood, Huner said, is “a huge amount of sediment was deposited.” In fact, all that sediment filling up the Atchafalaya is one of the reasons Granger’s idealized Atchafalaya no longer runs as in the good old days.

“It will no longer be what it was. I wish there were whooping cranes flying by my home,” said Huner.

And while Louisiana wildlife officials actually are reintroducing the endangered whooping crane into the state landscape, Huner sees the eventual fate of the Atchafalaya as less optimistic. He said it eventually will fill up completely with sediment through future floods, and simply wind up a hardwood forest with channels running through it, much to the chagrin of the populations it sustains.
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Quoting aquak9:

LOL Thanks Aqua! Has your owner signed you up?

Q: How can your rescuers possibly pay for my pet's care for only $135.00?
A: The $135.00 fee for one pet is not for the cost of their care. It is to compensate the rescuers for their travel, cover website expenses, and provide a profit margin.

Well, at least they're honest about it! =)
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And by the way I'm not telling anybody to mark my words.2010 was a "lesson learned".Hopefully people arn't to dependent on these forecast and then will have to pay the price down the road...
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I know some of you all arn't proud to see me.But I'm back on for a short while.Anyway I wasn't surprised by this forecast at all from Noaa.But I feel like people are underestimating this season.Hello? Neutral year...warm sst and a more western A/B high this year could mean trouble for someone later down the road.2010 by the end of this year will probally just be a distant memory for many.People were hyping last hurricane season way to much.Yeah sure it was active.But it doesn't matter how active a season is...It's where the storms go.
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Member Since: August 13, 2005 Posts: 192 Comments: 28115
Man, they wiped all the rain off the map for SEC&SEFL for the next 7 days, grrrrr.

Rather staggering forecast from NOAA. Especially since the Ducks most likely will be headed farther westish this year.
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Mornin'...Rain on the way to central Texas again this year? Wow! A TRUE sign of the I can go spend all of my money (with a donation to Portlight, of course) :_)
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434. IKE
Quoting aquak9:
I want some of what Ike's on.
Yo bud!
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I want some of what Ike's on.
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431. IKE
Quoting aquak9:
Ike- that's almost seven days out. geeesh.
Gives us something to look forward to:)

Another WOOHOO!
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429. Ylee
Well, Aqua, it'll give you something to look forward to!
"It's Sunday, that means only five days to go before I get that quarter inch of rain! Woo-hoo!"
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Good morning from wet Puerto Rico. Only,a few times the NWS puts the chance of rain in 100%,and that number is what they have for today in San Juan.See my Puerto Rico Blog for details.
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Ike- that's almost seven days out. geeesh.
Member Since: August 13, 2005 Posts: 192 Comments: 28115
About .06 so far here. Planted a small area with grass seed and the wild rabbits are coming out at night and muching on it. Glad something is enjoying the only green area that I once called a lawn.
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423. IKE
Quoting clwstmchasr:

Just to tease us it will be virga:(
I'll probably get .01 inches of

Looks like a quarter to a half inch on the GFS. No drought buster but it will settle the dust for a day or two.

I've had 1.36 inches of rain since April 6th.
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421. IKE

Quoting PakaSurvivor:
Good Morning Ike.

Are you drawing these maps to get us excited over rain and then let us down when it does show?
I'm trying to give hope for a drought stricken area....I hope.
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Another interesting cluster of earthquakes this week:
20May, a magnitude5.3quake ~28miles(~45kilometres) at 88.9degrees(E) from FukushimaDaichi
14May, a magnitude5.2quake ~30miles(~48kilometres) at 54.1degrees(NE) from FukushimaDaichi
13May, a magnitude6.2quake ~21miles(~34kilometres) at 97.6degrees(E) from FukushimaDaichi

The lone red dot represents centralTokyo
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Good Morning Ike.

Are you drawing these maps to get us excited over rain and then let us down when it does show?
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418. IKE
From this mornings Tallahassee discussion....



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417. MahFL
I'll believe rain when I see it..........
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416. IKE
162 hour 6Z GFS shows some rain in the SE USA.....

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Is this a record flow rate at the ORCS??
Looks like it.
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Maybe an Omeka like storm?
I seriously doubt it conditions aren't that great there
why don't we talk about the storm that will likely be the Northern Hemisphere's first typhoon.
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g'morning folks. It's foggy, thick and wet. That never happens- this fog wasn't here yesterday.

Ominous, I tell ya, ominous.
Member Since: August 13, 2005 Posts: 192 Comments: 28115
412. Ylee
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Quoting AussieStorm:

If it's west of Hawaii, it will continue west, no need to issue special warning, maybe only shipping warnings.

Yes, but it's moving east... closer to Hawaii
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Quoting trHUrrIXC5MMX:
Interesting feature west of Hawai'i!

Special Tropical Weather Outlooks could be issued regarding this???

If it's west of Hawaii, it will continue west, no need to issue special warning, maybe only shipping warnings.
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Quoting trHUrrIXC5MMX:
Interesting feature west of Hawai'i!

Special Tropical Weather Outlooks could be issued regarding this???

Next Invest... for sure
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Interesting feature west of Hawai'i!

Special Tropical Weather Outlooks could be issued regarding this???
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Goodnight Pottery just glad I didn't have to fill out an eyewitness form.
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Quoting presslord:

precisely why they don't celebrate Christmas at Georgia Tech...they can't find three wise men...or a virgin...

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Quoting gordydunnot:
Pottery I thought it might be a little to obvious but a first I didn't notice the long neck. Glad you pointed that out most unusual, don't know what I was looking at.

Yes, I know.
It's called 'selective vision' and it's pretty common.
It's the inability to see anything except what you are looking at.
Very strange.


See you guys tomorrow.
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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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