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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1019. aquak9
we can see the lightning from here, tho, SSI.

would rather see the rain.
Member Since: August 13, 2005 Posts: 163 Comments: 25732
Interesting wave over Venezuela.

Member Since: September 2, 2009 Posts: 130 Comments: 21091
Haven't seen the blog this dead in a while, let's try to get it going.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1015. Ossqss
Here is the Astronomy Picture of the Day or movie from May 10th :)

BTW, does anyone know how many Earths it would take to fill the hole in the arch?
Member Since: June 12, 2005 Posts: 6 Comments: 8185
1014. xcool






Member Since: September 26, 2009 Posts: 2 Comments: 15620
1013. Ossqss
1012, correct. We did have a G2 last week :)

http://www.swpc.noaa.gov/


If ya don't have the link -- this is a pretty cool new tool for us.

http://sdo.gsfc.nasa.gov/


Member Since: June 12, 2005 Posts: 6 Comments: 8185
The Sun seems to be slowly emerging from its extended solar minimum with five solar eruptions over a four-day period (May. 5 - 9, 2010). SOHO captured the action with its C2 coronagraph in which the sun is blocked out (by the circular occulting disk in the center of the image) to reveal the faint structures in the corona. The white circle represents the size of the Sun. These eruptions were not Earth-directed, and there is little evidence that effects from any of these blasts were felt here at Earth.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
Tornadodude getting ready to intercept a cell on xtremehurricanes.com tornado chase webcam
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1010. beell
Quoting Chucktown:


If you are into old school Weather Channel, hers's a cool link.


Link


If you're really bored, download the "Weather Channel Emulator". Used to have it running on a spare computer at work. Probably takes a couple hours to set it up and feed in the appropriate links. Add your own cities and icons and music.

Never could get the radar to work right.

Weatherstar 400 Emulator

Download Page
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Quoting P451:
Since we all BS about everything on here and all of us into weather are mostly into our gardening and what have you....



Here's a look at my garden.

Click for IMAGE of the whole yard, garden, etc.


(I linked instead of posted because it's big)


And, here's a video of the yard. Camera sucks so apologies about the distortion.

Very beautiful.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Beautiful house and garden P451!
Member Since: June 9, 2007 Posts: 4 Comments: 15776
Quoting DestinJeff:


Vivian Brown .... been there for ages


If you are into old school Weather Channel, hers's a cool link.


Link
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beautiful garden p451
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Quoting P451:
Since we all BS about everything on here and all of us into weather are mostly into our gardening and what have you....



Here's a look at my garden.

Click for IMAGE of the whole yard, garden, etc.


(I linked instead of posted because it's big)


And, here's a video of the yard. Camera sucks so apologies about the distortion.



very nice.. I was surprised you didn't narrate the video.. thanks for sharing!
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1004. pottery
Post 1000. Very nice. Wow!
Member Since: October 24, 2005 Posts: 0 Comments: 24022
Quoting DestinJeff:
who is on xtremehurricanes live cam right now? is tornadodude web-casting?


I am still wondering how to get the live cam from where he is

Any help would be nice
Taco :o)
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1002. pottery
Hey P451, that looks good. And lots of edible green stuff too. Nice.
Member Since: October 24, 2005 Posts: 0 Comments: 24022
Quoting P451:
Since we all BS about everything on here and all of us into weather are mostly into our gardening and what have you....



Here's a look at my garden.

Click for IMAGE of the whole yard, garden, etc.


(I linked instead of posted because it's big)


And, here's a video of the yard. Camera sucks so apologies about the distortion.



Very beautiful garden, I envy it. lol
Member Since: July 24, 2005 Posts: 407 Comments: 19076
may be haveing oil in the gulf is a good thing


it will help slow dow the rate the sea temper are going up
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PAST 24 HOURS

Riser Insertion Tube Leak Mitigation Tactic is Tested

The Unified Area Command reports that overnight the Riser Insertion Tube Tool was successfully tested and inserted into the leaking riser, capturing some amounts of oil and gas. The oil was stored on board the Discoverer Enterprise drill ship 5,000 feet above on the waters surface, and natural gas was burned through a flare system on board the ship.

The test was halted temporarily when the tube was dislodged, but technicians have fully inspected the system and have re-inserted the tool. While not collecting all of the leaking oil, this tool is an important step in reducing the amount of oil being released into Gulf waters

Secretary Salazar and Secretary Napolitano issued a joint statement on these efforts: Today, BP attempted another test to contain some of the oil leaking from the riser. This technique is not a solution to the problem, and it is not yet clear how successful it may be. We are closely monitoring BP's test with the hope that it will contain some of the oil, but at the same time, federal scientists are continuing to provide oversight and expertise to BP as they move forward with other strategies to contain the spill and stop the flow of oil. We will not rest until BP permanently seals the wellhead, the spill is cleaned up, and the communities and natural resources of the Gulf Coast are restored and made whole.

Progress Made in Relief Well Drilling Preparations

MMS reports the Development Driller III, which will drill the first relief well, has finished running blowout preventer (BOP) stack and riser and is currently latching the BOP to the wellhead for the first relief well. The Development Driller II, which will drill the second relief well, is on location and is making preparations for initiating the drilling process and performing BOP maintenance.

Wildlife Surveillance and Recovery Teams Search for Impacted Wildlife

Seven Fish and Wildlife Service surveillance and recovery teams were deployed from the Mobile, Ala., Command Center four via land with two support crews; two via sea on 2 separate vessels; and one via helicopter over-flight.

Two helicopters conducted flights at low levels to spot wildlife along the Biloxi Marsh, Breton Sound, SW Pass and Pas-A-Loutre. One helicopter conducted an early morning IR Thermal Imagery pilot study flight with Department of Defense scientists. The second helicopter continued its flights with DOI Assistant Secretary of Fish and Wildlife and Parks Tom Strickland over New Orleans area, Houma Command Center and SE Louisiana Refuge Complex in Lacombe, La., to observe potentially impacted wildlife.
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Oil may already be in the loop current.
http://wala.m0bl.net/w/main/story/11060759/
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Looks like this wave will have to hang together until it gets to the SW Carib. before it gets away from the shear that is bothering it now.
Member Since: October 24, 2005 Posts: 0 Comments: 24022
Hey guys do we still have anybody at the Weather Channel besides Jim Cantore that is considered part of the "old school" Weather Channel?
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Quoting pottery:

LOL it has stopped now. But there was one roll of thunder just a few mins ago! Gonna be a dark night anyway. Lots of cloud overhead.


lol, a thunderstorm day is define as when thunder is heard by the reporting station. So today was a thunderstorm day even if it was a sprinkle of rain lol
Member Since: July 24, 2005 Posts: 407 Comments: 19076
988. xcool
lol yeah
Member Since: September 26, 2009 Posts: 2 Comments: 15620
Quoting Weather456:


Its a start my friend! Hopefully you'll get some more tonight and on Monday.

LOL it has stopped now. But there was one roll of thunder just a few mins ago! Gonna be a dark night anyway. Lots of cloud overhead.
Member Since: October 24, 2005 Posts: 0 Comments: 24022
Quoting xcool:
I can't STOP LMAO AT OZ VIDEO .


Link



lol...wow i did not hit this guy....but pretty close call there.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
985. xcool
I can't STOP LMAO AT OZ VIDEO .


Link

Member Since: September 26, 2009 Posts: 2 Comments: 15620
Quoting pottery:
Good evening all.
Contrary to what the Sat. Images have been showing over the past several hours, it has only just started to rain here.(Trinidad 11n61w)
Nothing heavy.
Enter 'Pairco' in the search box, top of this page.
Piarco is about 5 miles north of me.


Its a start my friend! Hopefully you'll get some more tonight and on Monday.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Member Since: July 15, 2006 Posts: 169 Comments: 53296
982. beell
BP: Mile-long tube sucking oil away from Gulf well
By JEFFREY COLLINS and JASON DEAREN Associated Press Writers © 2010 The Associated Press
May 16, 2010, 3:37PM


Computer models show the black ooze may have already entered the loop current — which is the largest in the Gulf — said William Hogarth, dean of the University of South Florida's College of Marine Science. A research vessel is being sent to the Gulf on Tuesday to collect samples and learn more.

One computer model shows that the oil has already entered the current, while a second model shows the oil is 3 miles from it — still dangerously close, Hogarth said. The models are based on weather, ocean current and spill data from the U.S. Navy and the National Oceanic and Atmospheric Administration, among other sources.
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Good evening all.
Contrary to what the Sat. Images have been showing over the past several hours, it has only just started to rain here.(Trinidad 11n61w)
Nothing heavy.
Enter 'Pairco' in the search box, top of this page.
Piarco is about 5 miles north of me.
Member Since: October 24, 2005 Posts: 0 Comments: 24022
Member Since: July 15, 2006 Posts: 169 Comments: 53296
Its not
Quoting superweatherman:


IT WILL NOT MATTER AT THIS POINT IF THE GULF IS NOT AT 27C IT ONLY TAKE A LITTLE TO WARM IT UP.




I BELIEVE THAT THIS YEAR WILL BE VERY CLOSE TO PASS 2005 RECORD OR EVEN GO OVER BY 1 MAYBE 2 STORMS
Thats not good.
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Quoting Weather456:
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






HI 456 I FORGOT THIS LAST YEAR VS THIS YEAR



VS
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Member Since: July 15, 2006 Posts: 169 Comments: 53296
is in in oak in that cell i got up in the previous post
Member Since: July 15, 2006 Posts: 169 Comments: 53296
974. JRRP
102 hr

168 hr
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tornadodude reports lowering and rotation...
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Member Since: July 15, 2006 Posts: 169 Comments: 53296
971. xcool
Stormchaser2007 hi CycloneOz .
Member Since: September 26, 2009 Posts: 2 Comments: 15620
Quoting KEEPEROFTHEGATE:
where is he oz


xremehurricanes.com
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969. Skyepony (Mod)
Nice ASCAT of 93A


93A is bottom center in the Arabian Sea, 92B is to the right of there.

Checking the rainrate 92B is putting out more..
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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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