Record Atlantic SSTs continue in the hurricane Main Development Region

By: Dr. Jeff Masters , 8:03 PM GMT on May 15, 2010

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Sea Surface Temperatures (SSTs) in the Atlantic's Main Development Region for hurricanes had their warmest April on record, according to an analysis of historical SST data from the UK Hadley Center. SST data goes back to 1850, though there is much missing data before 1910 and during WWI and WWII. The area between 10°N and 20°N, between the coast of Africa and Central America (20°W - 80°W), is called the Main Development Region (MDR) because virtually all African waves originate in this region. These African waves account for 85% of all Atlantic major hurricanes and 60% of all named storms. When SSTs in the MDR are much above average during hurricane season, a very active season typically results (if there is no El Niño event present.) SSTs in the Main Development Region (10°N to 20°N and 20°W to 85°W) were an eye-opening 1.46°C above average during April. This is the third straight record warm month, and the warmest anomaly measured for any month--by a remarkable 0.2°C. The previous record warmest anomalies for the Atlantic MDR were set in June 2005 and March 2010, at 1.26°C.


Figure 1. The departure of sea surface temperature (SST) from average for May 13, 2010. Image credit: NOAA/NESDIS.

What is responsible for the high SSTs?
As I explained in detail in a post on record February SSTs in the Atlantic, the Arctic Oscillation (AO) and its close cousin, the North Atlantic Oscillation (NAO), are largely to blame for the record SSTs. The AO and NAO are climate patterns in the North Atlantic Ocean related to fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores-Bermuda High. If the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), this creates a weak Azores-Bermuda High, which reduces the trade winds circulating around the High. During December - February, we had the most negative AO/NAO since records began in 1950, and this caused trade winds between Africa and the Lesser Antilles Islands in the hurricane Main Development Region to slow to 1 - 2 m/s (2.2 - 4.5 mph) below average. Slower trade winds mean less mixing of the surface waters with cooler waters down deep, plus less evaporational cooling of the surface water. As a result, the ocean heated up significantly, relative to normal, over the winter. Negative AO/NAO conditions have been dominant much of this spring as well, resulting in further anomalous heating of the MDR waters. This heating is superimposed on the very warm global SSTs we've been seeing over the past few decades due to global warming. Global and Northern Hemisphere SSTs were the 2nd warmest on record this past December, January, and February, the warmest on record in March, and will likely be classified as the warmest or second warmest on record for April, since NASA just classified April as the warmest April on record for the globe. We are also in the warm phase of a decades-long natural oscillation in Atlantic ocean temperatures called the Atlantic Multi-decadal Oscillation (AMO). This warm phase began in 1995, and has been partially responsible for the high levels of hurricane activity we've seen since 1995.

What does this imply for the coming hurricane season?
The high April SST anomaly does not bode well for the coming hurricane season. The three past seasons with record warm April SST anomalies all had abnormally high numbers of intense hurricanes. Past hurricane seasons that had high March SST anomalies include 1969 (0.90°C anomaly), 2005 (1.19°C anomaly), and 1958 (0.97°C anomaly). These three years had 5, 7, and 5 intense hurricanes, respectively. Just two intense hurricanes occur in an average year. The total averaged activity for the three seasons was 15 named storms, 11 hurricanes, and 6 intense hurricanes (an average hurricane season has 10, 6, and 2.) Both 1958 and 2005 saw neutral El Niño conditions, while 1969 had a weak El Niño.

The SSTs are already as warm as we normally see in July between Africa and the Caribbean, and we have a very July-like tropical wave approaching the Lesser Antilles Islands this weekend. However, wind shear is still seasonably high, and the tropical waves coming off of Africa are still too far south to have much of a chance of developing. The GFS model is indicating that shear will start to drop over the Caribbean the last week of May, so we may have to be on the watch for tropical storms forming in the Caribbean then.

For those of you interested in a more detailed look at the early season tropical weather outlook, consult the excellent wunderblogs of StormW and Weather456. I'll be back with a new post on Monday.

Jeff Masters

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Quoting Hurricanes101:
wishcasting?

cuz some of us feel that there could be development in the SW Caribbean next week?

Really??

Wow guess we just shouldnt talk about it at all then lol. So when should I be back to talk tropics? June 13th? Ok see you guys then lol


Better solution is to wait to see IF something develops then discuss where it may go or develop further, the models, especially the GFS is very climatologically driven beyond 7 days.
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GOM SST May 15 2010



2009



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One can follow the Global 26C Isotherm here


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wishcasting?

cuz some of us feel that there could be development in the SW Caribbean next week?

Really??

Wow guess we just shouldnt talk about it at all then lol. So when should I be back to talk tropics? June 13th? Ok see you guys then lol
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Quoting Patrap:


Wishcasting on the wunderground,...explained



they just have to wait their turn.. :)
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914. xcool
lmao pat
Member Since: September 26, 2009 Posts: 2 Comments: 15603
You all are focusing on the surface temps and not looking at the depth of the warm layer.

You should not use that to justify your point. Everything was fine with what you said up to the subtropical jet.

The requirement is a dept of 50 meters of waters above 26.5C.

Current dept of 26.5 waters is well above 50 meters over the Caribbean



Member Since: July 24, 2005 Posts: 407 Comments: 19076


Wishcasting on the wunderground,...explained

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911. xcool
MJO wet pulse


Member Since: September 26, 2009 Posts: 2 Comments: 15603
910. xcool
lolol
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Quoting HaboobsRsweet:


Right now the overall pattern is too far south for solid development in the carb, gulf or atlantic. The front moving through srn US today was def strong enough to spin something off its sheer line if it was farther north. We are still in a transition pattern. The STJ is not in the right position yet either. The overall pattern needs to shift and it wont happen in a night or a few days. The Gulf is also warming quickly but still could use another degree. You all are focusing on the surface temps and not looking at the depth of the warm layer.


Thank you, well said. The wishcasting is already ridiculous and we are not even officially in hurricane season.
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908. xcool



Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting Hurricanes101:


obvious? not sure what you mean by that


Right now the overall pattern is too far south for solid development in the carb, gulf or atlantic. The front moving through srn US today was def strong enough to spin something off its sheer line if it was farther north. We are still in a transition pattern. The STJ is not in the right position yet either. The overall pattern needs to shift and it wont happen in a night or a few days. The Gulf is also warming quickly but still could use another degree. You all are focusing on the surface temps and not looking at the depth of the warm layer.
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Quoting Chucktown:


NHC is generally conservative and always go with a range. Most likely it will be 12-15 named storms for 2010.
Lets hope thats the case.
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905. xcool
i think 16-5-8
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting xcool:
NOAA may 20. ATLC HURRICANE OUTLOOK/.


NHC is generally conservative and always go with a range. Most likely it will be 12-15 named storms for 2010.
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Quoting xcool:
NOAA may 20. ATLC HURRICANE OUTLOOK/.


Thats Thursday, cant wait.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
902. xcool
NOAA may 20. ATLC HURRICANE OUTLOOK/.
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting HaboobsRsweet:
My forecast is that we will not see a TD or named storm before June 13th. Just not liking hte synoptic pattern. Can not ignore the obivous.


obvious? not sure what you mean by that
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My forecast is that we will not see a TD or named storm before June 13th. Just not liking hte synoptic pattern. Can not ignore the obivous.
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Quoting mobilegirl81:
There are strong signals that this season will have the same affects as the 1995,1998,2002,2003,2004,2005,2008 seasons have had "active". Its just a question of how intense and where it will have an affect.Thats anyones guess. Just be ready. If NOAA comes out with a range of 19-21 storms like they did in 2005, Im putting a helmet on.

Yeah it does look that way. I don't know if i cam go through another Ivan or Katrina.
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Member Since: July 15, 2006 Posts: 163 Comments: 52173
This years season might be comparable to 1950's hurricane season Link does anyone agree??
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There are strong signals that this season will have the same affects as the 1995,1998,2002,2003,2004,2005,2008 seasons have had "active". Its just a question of how intense and where it will have an affect.Thats anyones guess. Just be ready. If NOAA comes out with a range of 19-21 storms like they did in 2005, Im putting a helmet on.
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Member Since: July 15, 2006 Posts: 163 Comments: 52173
@stormhank

Link
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I read in one of DR.Masters blog from earlier this week that if a storm passed over the oil spill the waves n wind would prob prevent any affects on the storms intensity.. do you all agree??
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Somebody upstairs was on this flight.

From St Petersburg (FL) Times on line:

Relief flight to Haiti crashes after takeoff in Clearwater; remarkably, all survive
By Drew Harwell, Times Staff Writer
Posted: May 16, 2010 11:09 AM

CLEARWATER — A small plane carrying humanitarian aid for Haiti crashed into a home Sunday morning about a half-mile from the Clearwater Air Park — and, remarkably, nobody on the ground was hurt and all three passengers survived.

"God had his hand on this," said Mary-Lynn Cetroli, whose kids were playing in the back yard just 10 minutes before the plane came down there.

The trio onboard the Piper PA 46-350P — pilot Ernesto Gonzalez, 48, and passengers Charles Uslander, 54, and Daisy Schneider, 16 — crash landed about a block north of Drew Street around 10:15 a.m.

Uslander was taken to Bayfront Medical Center on a trauma alert. Clearwater police said the injuries are not believed to be life-threatening.

The cause of the crash is not yet determined, though residents who helped rescue the passengers guessed the plane was carrying too much weight.

Dennis Roper, a local pilot and chairman of the Air Park's advisory board, said Gonzalez flew into Clearwater from Mexico on Friday and took on relief supplies and about 96 gallons of fuel.

The single-engine plane struggled to climb for about half a minute after takeoff but "couldn't get enough altitude," Roper said.

The plane skimmed a roof and the tops of two oak trees before snapping a telephone pole and crashing down in the back yard of 305 Patricia Ave.

Sausage, bacon and coffee were still on the table from a Sunday breakfast when Richard Cetroli heard an explosion outside his house and saw a fireball out the front window. Running to look out back, he saw a plane with its wings on fire and heard a cry for help.

"Get me out of here!" he said he heard a woman call.

He ran to the plane, pulled open the door and yanked her out.

Just then, three young men from the neighborhood ran up and pulled the other two from the plane.

Cetroli said he called 911 and paramedics arrived within minutes.

The plane's front end had snapped from the fuselage and landed in the house's side yard.

Roper said the pole snapped one of the plane's wings, where the fuel is stored, putting distance between the passengers and the plane's explosion.

"They were very, very lucky," Roper said. "That fireball was 60, 70 feet in the air."

The crash sparked fires between two homes, creating a "big plume of black smoke," said Clearwater resident Tracy Enos, who lives nearby.

Clearwater firefighters said a fire was showing from the home's attic but that the people in the home had escaped without injury.

They identified them as the Cetrolis, Katherine Swartz, 68; twin 9-year-old girls and a 7-year-old boy.

Tammie Lakins was at her home on Harding Street when she first heard the plane.

"You could hear the plane coming over top of us. You could hear it sputtering," Lakins said. "I was in my living room and, once you heard that sputtering and that major boom, you just sat in your chair and waited for it to hit the house."

"The next thing you heard was this big crash and everything in the neighborhood just shook," she said. "It was the most horrible noise you can imagine."

Neighbors began grabbing hoses to soak the flames, Lakins said. Two men carried the pilot out of the plane and laid him on a front lawn.

"I'm still shaking," Lakins said. "It was just so close to home."

The plane, according to an FAA aircraft database, was manufactured in 2007 and originally registered in Midland, Texas. Earlier this month, its registration was canceled and the plane was exported to Mexico.

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Quoting CybrTeddy:
Well, now the GFS has model support, chances are increasing we might have a tropical cyclone develop in the Caribbean by late this week - early next.
Well we need rain real bad in here in the Caymans but we don't need a tropical cyclone to disrupt my travel plans on May 27.
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Quoting Weather456:


I'm not discounting development per my blog but looking the high levels of shear out there.
Yeah. There is a small window of opportunity, and if it can't develop in that time I doubt we'll see development.
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Quoting Patrap:
55knots of shear will do dat...
also pull anything that should popup ne ward out to open atlantic any treats will be jamaica cuba hati central bahaman island chain for early dev.
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888. xcool



Red tracksanddots are during a -NAO


i was do web searches ON -NAO
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Quoting Hurricanes101:


I do feel we could easily see development in the SW Caribbean in about a week to 10 days.


I'm not discounting development per my blog but looking the high levels of shear out there.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Shear expected to drop across the S Caribbean, remains high north of 15N. Pattern expected to continue to June 1 but with less extremity.
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Quoting Weather456:
anything moving close to 20N will get ripped apart by shear or struggle.


I do feel we could easily see development in the SW Caribbean in about a week to 10 days.
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55knots of shear will do dat...
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anything moving close to 20N will get ripped apart by shear or struggle.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
AFTERNOON ALL... just a couple of quick questions...Could the oil spill in gulf have any affect on a hurricane if one passed over the spill?? and second does anyone have any indicators on what the steering and shear will be for this season?? As always thanks for all your help and advice!!!
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880. xcool
..... I wish can post, video from joe
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Quoting IKE:
If Bastardi thinks something could affect the SE USA in early June I wonder if this "possible development?", might have anything to do with it....that may get the tropics involved in southeast US weather the first week of June

The first week of June is 2 weeks away.
yep won't be long now by end of the week will be less then ten days away
Member Since: July 15, 2006 Posts: 163 Comments: 52173
Pottery is getting wet:

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877. IKE
First good news I've read.
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BP: Mile-long tube sucking oil away from Gulf well

by Jason Dearen and Jeffrey Collins / Associated Press

wwltv.com

Posted on May 16, 2010 at 1:54 PM

HAMMOND, La. -- BP says a mile-long tube is drawing most of the oil away from a well that's spewed millions of gallons of crude into the Gulf of Mexico.

BP spokesman Mark Proegler said Sunday that the contraption was hooked up successfully to a tanker at the surface as crews gained partial control on the leak for the first time. Proelger said it was sucking most of the oil from the leak.

The tube was carefully placed into the 21-inch piping at the seafloor by engineers gingerly steering deep-sea robots.

The company has spent three weeks trying to contain the leak that's been fouling the Gulf of Mexico, and the latest effort had several setbacks.

(Copyright 2010 by The Associated Press. All Rights Reserved.)

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19:15 UTC
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874. IKE
If Bastardi thinks something could affect the SE USA in early June I wonder if this "possible development?", might have anything to do with it....that may get the tropics involved in southeast US weather the first week of June

The first week of June is 2 weeks away.
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873. xcool
ECMWF BEST ALL YEARs ..opps caps lock
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Quoting Weather456:


still to early to call...but it will be monitored as it heads west.
Definetly.
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Well, now the GFS has model support, chances are increasing we might have a tropical cyclone develop in the Caribbean by late this week - early next.
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BP: Tube is siphoning oil from leak
'So far it's working extremely well,' company VP says of strategy
---and the link---
http://www.msnbc.msn.com/id/37177037/ns/gulf_oil_spill/

I wonder if we can and should actually belive these liars?
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Quoting KEEPEROFTHEGATE:
yeah as more jump on board the chances increases with its outcome
Yeah especially the ECMWF. I think that will be the model to follow in 2010, imo.
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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.