TSR predicts very active hurricane season; Atlantic May MDR SSTs warmest on record

By: Dr. Jeff Masters , 1:51 PM GMT on June 10, 2010

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The British private forecasting firm Tropical Storm Risk, Inc. (TSR) has joined the ranks of NOAA and Colorado State University in calling for an exceptionally active 2010 Atlantic hurricane season. The latest TSR forecast issued June 4 calls for 17.7 named storms, 9.5 hurricanes, 4.4 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 181% of average. These numbers are much above the 50-year average of 10 named storms, 6 hurricanes, and 2 intense hurricanes, and are an increase from their April forecast of 16.3 named storms, 8.5 hurricanes, and 4 intense hurricanes. The TSR June forecast numbers are the highest they've ever gone for in the eleven years they've been issuing Atlantic hurricane season forecasts. TSR predicts a 85-90% chance that activity will rank in the top 1/3 of years historically, and a 85% chance that U.S. landfalling activity will be above average. TSR rates their skill level as 20-34% higher than a "no-skill" forecast made using climatology, though an independent assessment by the National Hurricane Center (Figure 1) gives them somewhat lower skill numbers.

TSR projects that 5.7 named storms will hit the U.S., with 2.5 of these being hurricanes. The averages from the 1950-2009 climatology are 3.2 named storms and 1.5 hurricanes. They rate their skill at making these June forecasts for U.S. landfalls at 10 - 17% higher than a "no-skill" forecast made using climatology. In the Lesser Antilles Islands of the Caribbean, TSR projects 1.8 named storms, 0.8 of these being hurricanes. Climatology is 1.1 named storms and 0.5 hurricanes.

TSR cites two main factors for their forecast of an exceptionally active season:

1) Their model predicts that sea surface temperatures will be 0.6°C warmer than average in August and September over the Main Development Region (MDR) for Atlantic hurricanes. This is the area between 10°N and 20°N, between the coast of Africa and Central America (20°W - 80°W). It is called the Main Development Region 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.)

2) Their model predicts slower than normal trade winds in August and September over the Main Development Region (MDR). Trade winds are forecast to be 1.2 meters per second (about 2.7 mph) slower than average. This would create more spin for developing storms, and allow the oceans to warm up, due to reduced mixing of cold water from the depths and lower evaporational cooling.


Figure 1. Comparison of the percent improvement over climatology for May and August seasonal hurricane forecasts for the Atlantic from NOAA, CSU and tropicalstormrisk.com (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.

2010 hurricane season forecasts from CSU and NOAA
NOAA's 2010 Atlantic hurricane season forecast, issued May 27, called for 18.5 named storms, 11 hurricanes, 5 major hurricanes, and an ACE index 210% of normal (using the mid-point of their range of numbers.) The 2010 Atlantic hurricane season forecast from Colorado State University (CSU) issued on June 2 called for 18 named storms, 10 hurricanes, and 5 intense hurricanes. So, the consensus forecast from NOAA, CSU, and TSR is 18 named storms, 10 hurricanes, and 5 intense hurricanes. The June forecast numbers from all three groups were the highest they've ever gone for in their history of issuing Atlantic hurricane season forecasts.

May SSTs in the tropical Atlantic set a new record
Sea Surface Temperatures (SSTs) in the Atlantic's Main Development Region for hurricanes had their warmest May 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. SSTs in the Main Development Region (10°N to 20°N and 20°W to 80°W) were a remarkable 1.51°C above average during May. This is the fourth straight record warm month, and the warmest anomaly measured for any month. The previous record warmest anomaly for the Atlantic MDR was 1.46°C, set last month. Third place goes to June 2005 and March 2010, with a 1.26°C anomaly. 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, though global warming and Atlantic Multidecadal Oscillation (AMO) also play a role. However, trade winds over the tropical Atlantic have increased to near-normal speeds over the past week, since the Bermuda-Azores High has strengthened to near-normal pressures. The Bermuda-Azores High and its associated trade winds are forecast to increase to above average strength during mid-June, according to the latest runs of the GFS model. This means that Atlantic SST anomalies have probably peaked for the year, and we can anticipate that the June SST anomaly in the MDR will not be as great as the May anomaly--and may even fall below the June record set in 2005.


Figure 2. The departure of sea surface temperature (SST) from average for June 10, 2010. Image credit: NOAA/NESDIS.

Oil spill update
Light southeast or south winds of 5 - 15 knots will blow today through Tuesday, according to the latest marine forecast from NOAA. These winds will keep oil near the beaches of Alabama, Mississippi, and the extreme western Florida Panhandle, according to the latest trajectory forecasts from NOAA and the State of Louisiana. The latest ocean current forecasts from the NOAA HYCOM model are not predicting eastward-moving ocean currents along the Florida Panhandle coast this week, and it is unlikely that surface oil will affect areas of Florida east of Pensacola. Long range surface wind forecasts from the GFS model for the period 8 - 14 days from now show a southeasterly wind regime, which would prevent any further progress of the oil eastwards along the Florida Panhandle, and would tend to bring significant amounts of oil back to the shores of eastern Louisiana next week. If you spot oil, send in your report to http://www.gulfcoastspill.com/, whose mission is to help the Gulf Coast recovery by creating a daily record of the oil spill.


Figure 3. The oil spill as imaged on June 9, 2010, by NOAA's Terra satellite. The spill appears highly reflective in the sunglint portion of the image.

Oil spill resources
My post, What a hurricane would do the Deepwater Horizon oil spill
NOAA's fact sheet on Hurricanes and the Oil Spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
Oil trajectory forecasts from NOAA
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
Synthetic Aperture Radar (SAR) imagery from the University of Miami

I'll have a new post on Friday. The tropical Atlantic is quiet right now, with no models predicting tropical cyclone development over the next seven days.

Jeff Masters

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Quoting MiamiHurricanes09:
Exactly. I don't know what "sleetman1" is talking about.


Does any of us?

Really does he realize that Neutral conditions don't exactly mean we will see less storms than if we go into La Nina? In fact you saw the table Dr M had in his last blog; Neutral seasons on average are more active than La Nina seasons
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Quoting extreme236:


BP shares on the NYSE fell to a 13 year low on Wednesday, but have rallied about 15% since then.


Yeah, it went all the way to $29 and is now about $33.75. I still wouldn't want to own the stock right now.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting sleetman1:
i agree miami hurricane el nino is still there and thats why the strong shear is continuing over the caribbean..until that changes the waves will develop so far south and keep going into s america..GOM is clear for quite a while..i just refer you back to 2006 very close to the same conditions..we will just have to wait and see...


No, 2006 had an El Nino that developed for the season. This season has one that is going away, with a developing La Nina. Two completely different things. The low latitude waves aren't unusually either. Those will naturally emerge at higher latitudes later in the season.
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Quoting CaneWarning:


Foreign companies trade on the NYSE. The BP ADR trades on the NYSE. BP trades on the London Stock Exchange separately. In fact, in London the price of BP is almost 400.


BP shares on the NYSE fell to a 13 year low on Wednesday, but have rallied about 15% since then.
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The TUTT over the Caribbean should inhibit any development in the near term.
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Quoting PcolaDan:


BP is not just a British company. They are traded on the New York Stock Exchange. Only 40% of the stocks are owned by British, and none by the British Government. Their head office is in London.


Percentage of shares in issue
Range of holdings Institutions Individuals Total
By principal area
UK 33 7 40%
US 25 14 39%
Rest of Europe 10 - 10
Rest of World 7 - 7
Miscellaneousc 4 - 4
79 21 100


Foreign companies trade on the NYSE. The BP ADR trades on the NYSE. BP trades on the London Stock Exchange separately. In fact, in London the price of BP is almost 400.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting extreme236:
Shear levels are actually pretty close to average for this time of year across the basin, and even below average in areas.
Exactly. I don't know what "sleetman1" is talking about.
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting wunderkidcayman:
we are going into La nina and La nina is developing but maybe shear is slow to respond to the change and it is kinda normal for this time of the season
Yeah. We had an El Nino and it literally disappeard in 3 months, the lingering effects of El Nino are still there.
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Shear levels are actually pretty close to average for this time of year across the basin, and even below average in areas.
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AOI

AOI

AOI

AOI

TS BUSTED FORECAST ALIBI
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we are going into La nina and La nina is developing but maybe shear is slow to respond to the change and it is kinda normal for this time of the season
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Quoting sleetman1:
that wave at 8 degrees is just to far south it will run into s america and will be destroyed ..the strong westerly shear in the caribbean will keep anything developing until at least until after mid july..we will see what happens then..no la nina developing thats for sure at leat not right now..its going to be a very slow hurricane season to get started..it looks like we are going to have to see what the cape verde season does..this year IMO reminds me of 2006...
There are a few things I need to correct you on, and they are:

1. Tropical waves don't get "destroyed" they just lose their convection, their energy is still in tact and that's all you need for a system to develop, you also need favorable conditions. And that brings me to number 2.

2. The westerly shear in the Caribbean should begin to die down as the TUTT lifts and a ULL aloft between Haiti and Cuba lifts. This should happen in less than 7 days, not 30 days.

3. Currently we are under neutral conditions and are forecasted by about 99.99% of models to enter into a weak to moderate La Nina. One thing that is causing unfavorable conditions is the lingering effects of the El Nino, this is due to the rapid turnaround in conditions in just 3 months.

4. It's still June and when looking at climatoligy, the only system to develop in the CATL was in 1979. We currently only look in the Caribbean and GOM for development, not the African coast. Now, I'm not saying that an African wave can't develop in June, it just doesn't seem likely.
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting MissNadia:


Hi,
I think BP is a british company. I have no idea what the laws would be over there.


BP is not just a British company. They are traded on the New York Stock Exchange. Only 40% of the stocks are owned by British, and none by the British Government. Their head office is in London.


Percentage of shares in issue
Range of holdings Institutions Individuals Total
By principal area
UK 33 7 40%
US 25 14 39%
Rest of Europe 10 - 10
Rest of World 7 - 7
Miscellaneousc 4 - 4
79 21 100
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Quoting gator23:

as noted before, they cant, their shareholders would have to hold a vote and agree which they wont because they still earn 65 million a month. Then a US judge would have to grant them a chapter 11 which no judge would. Filing for bankruptcy is not that easy.


I wouldn't be so sure of that. Bankruptcy is a fairly easy process, even for large companies.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting sleetman1:
that wave at 8 degrees is just to far south it will run into s america and will be destroyed ..the strong westerly shear in the caribbean will keep anything developing until at least until after mid july..we will see what happens then..no la nina developing thats for sure at leat not right now..its going to be a very slow hurricane season to get started..it looks like we are going to have to see what the cape verde season does..this year IMO reminds me of 2006...


MJO returns later this month, so mid-July is most likely later than when it actually will start. Plus what do you think those colder SST anomalies along the equator in the EPAC are a sign of? La Nina.
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Quoting DestinJeff:
Here is a friendly visual to help see where the TUTT is that is causing all the shear in the Carribbean ...
Actually what is causing the strong westerly shear in the Caribbean is the presence of a ULL aloft between the Cuba and Jamiaca region. It can be viewed by 200 MB vorticity:

Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting gator23:

as noted before, they cant, their shareholders would have to hold a vote and agree which they wont because they still earn 65 million a month. Then a US judge would have to grant them a chapter 11 which no judge would. Filing for bankruptcy is not that easy.


Hi,
I think BP is a british company. I have no idea what the laws would be over there.
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1278. aquak9
1274

oh I needed that laugh
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1277. scott39
Quoting MahFL:
The ban on shallow drilling was removed quietly 2 weeks ago. The deep water ban is still in place for NEW applications, those already authorised, I think, can procede with strict Gov inspections.
They need to quit drilling in water period! Theres enough oil under N Dakota to last for 200 years! Yea you still have enviromental risks on land, but its alot easier to stop a gusher! I Wonder how the Radical enviroMENTALists feel now about getting drilling for oil pushed out so deep in the GOM, and the disaster it caused for generations?
Member Since: June 13, 2009 Posts: 0 Comments: 6858



Great flag to fly today, All Clear.
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1275. IKE
Five years ago today she was making landfall. The B storm in 2005, Bret, started on June 28th.

Member Since: June 9, 2005 Posts: 23 Comments: 37858
1273. gator23
Quoting CaneWarning:
I think BP will file for bankruptcy to be honest.

as noted before, they cant, their shareholders would have to hold a vote and agree which they wont because they still earn 65 million a month. Then a US judge would have to grant them a chapter 11 which no judge would. Filing for bankruptcy is not that easy.
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1272. MahFL
The ban on shallow drilling was removed quietly 2 weeks ago. The deep water ban is still in place for NEW applications, those already authorised, I think, can procede with strict Gov inspections.
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Quoting DestinJeff:


can't even remember where/when I heard it ... also can't source it right now. maybe just a rumor, but I know I heard it from news source not a person.
Thanks Jeff. Talked with a friend last night who works offshore and he's not sure what his future holds. Hopefully, it's true and he and his family can stay rather than move for work...
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I see a spin in the wave south of 10N, near 55W.. Also has convection, it's eye fooling, it really looks like a TD. Anyone care to explain why the NHC is ignoring this? I know it's landbound and if it heads north, it gets sheared.. but this is currently an interesting feature.
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1269. scott39
Who or what is putting pressure on our government to make BP accountable? We are the who and the power of right to assemble and threaten jobs in congress and the senate is the what! If your waiting around for BP and the governmrnt to fix this without real pressure from us, Think again!
Member Since: June 13, 2009 Posts: 0 Comments: 6858
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1266. cg2916
Quoting StormW:


Right now, 10% or less.



Yeah, I think shear might be too strong.
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Here's an interesting page to follow, the American Association of Poison Control Centers is monitoring the gulf oil spill and health consequences.

Link
Member Since: April 26, 2009 Posts: 3 Comments: 3667
1261. cg2916
Quoting CaneWarning:


Did he? Well that's interesting because they leave for Europe tomorrow!
Quoting NttyGrtty:
Really? Hadn't heard that...do you have a source?


Actually, I heard it somewhere, but I can't find it on the Internet. Sorry guys.
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1257. cg2916
Quoting StormW:
Good morning to all, hot off the press!

TROPICAL WEATHER SYNOPSIS FRIDAY, JUNE 11, 2010 ISSUED 8:45 A.M.


Love it!

Now, what chances do you give for development of the wave that just came off of Africa *grabs pencil and notepad*?
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I think BP will file for bankruptcy to be honest.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
The wave near SA looks like a TD, just looks like one, not saying it is.
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1254. scott39
Who or what is putting accoutability and pressure on BP to fix this? No One and Nothing!!
Member Since: June 13, 2009 Posts: 0 Comments: 6858
Quoting cg2916:


No, Obama just lifted the ban,
Really? Hadn't heard that...do you have a source?
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Quoting cg2916:


No, Obama just lifted the ban,


Did he? Well that's interesting because they leave for Europe tomorrow!
Member Since: April 26, 2009 Posts: 3 Comments: 3667

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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.