CSU predicts highly active hurricane season; Cyclone Phet approaching Oman

By: Dr. Jeff Masters , 2:00 PM GMT en Junio 03, 2010

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A very active Atlantic hurricane season is on tap for 2010, according to the seasonal hurricane forecast issued June 2 by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). The CSU team is calling for 18 named storms, 10 hurricanes, and 5 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 185% of average. Between 1950 - 2000, the average season had 10 named storms, 6 hurricanes, and 2 intense hurricanes. But since 1995, the beginning of an active hurricane period in the Atlantic, we've averaged 14 named storms, 8 hurricanes, and 4 intense hurricanes per year. The new forecast is a step up from their April forecast, which called for 15 named storms, 8 hurricanes, and 4 intense hurricanes. The new forecast calls for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (51% chance, 31% chance is average) and the Gulf Coast (50% chance, 30% chance is average). The risk of a major hurricane in the Caribbean is also high, at 65% (42% is average.) This is the most aggressive early June forecast ever issued by the CSU group; the previous most aggressive such forecasts were for the 2006 and 2007 seasons, when the CSU team predicted 17 named storms, 9 hurricanes, and 5 intense hurricanes. Both of these forecasts did poorly, particularly the 2006 forecast, as only 10 named storms, 5 hurricanes, and 2 intense hurricanes were observed.

The forecasters cited four main reasons for an active season:

1) Weak La Niña conditions should develop by the most active portion of this year's hurricane season (August-October). The expected trend towards weak La Niña conditions should lead to reduced levels of vertical wind shear compared with what was witnessed in 2009.

2) Current SST anomalies are running at near-record warm levels. These very warm waters are associated with dynamic and thermodynamic factors that are very conducive for an active Atlantic hurricane season.

3) A weaker-than-normal Azores High prevailed during April-May. Weaker high pressure typically results in weaker trade winds that are commonly associated with more active hurricane seasons.

4) We are in the midst of a multi-decadal era of major hurricane activity, which began in 1995. Major hurricanes cause 80-85 percent of normalized hurricane damage.

Analogue years
The CSU team picked four previous years when atmospheric and oceanic conditions were similar to what we are seeing this year: weak El Niño to neutral conditions, well above-average tropical Atlantic SSTs, and above-average far North Atlantic SSTs during April - May. Those four years were 2005, the worst hurricane season of all time; 1969, the 3rd worst hurricane season of all time, featuring Category 5 Hurricane Camille which hit Mississippi; 1966, a relatively average year that featured Category 4 Inez that killed 1,000 people in Haiti; and 1958, a severe season with 5 major hurricanes. The mean activity for these five years was 17 named storms, 10 hurricanes, and 5 intense hurricanes, almost the same as the 2009 CSU forecast.

How accurate are the June forecasts?
The June forecasts by the CSU team over the past 12 years have had a skill 19% - 30% higher than a "no-skill" climatology forecast for number of named storms, number of hurricanes, and the ACE index (Figure 1). This is a decent amount of skill for a seasonal forecast, and these June forecasts can be useful to businesses such as the insurance industry and oil and gas industry that need to make bets on how active the coming hurricane season will be. Unfortunately, the CSU June 1 forecasts do poorly at forecasting the number of major hurricanes (only 3% skill), and major hurricanes are what do 80 - 85% of all hurricane damage (normalized to current population and wealth levels.) This year's June forecast uses the same formula as the past two years, which did quite well predicting the 2008 hurricane season (prediction: 15 named storms, 8 hurricanes, 4 intense hurricanes; observed: 16 named storms, 8 hurricanes, 5 intense hurricanes) and 2009 hurricane season (prediction: 11 named storms, 5 hurricanes, 2 intense hurricanes; observed: 9 named storms, 3 hurricanes, 2 intense hurricanes.) An Excel spreadsheet of their forecast skill (expressed as a mathematical correlation coefficient) show values from 0.44 to 0.58 for their June forecasts, which is respectable.


Figure 1. 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. The British firm Tropical Storm Risk (TSR) will issue their outlook for the 2010 Atlantic hurricane season on June 4. Image credit: Verification of 12 years of NOAA seasonal hurricane forecasts, National Hurricane Center.

NOAA's 2010 hurricane season forecast
NOAA issued their forecast for the upcoming Atlantic hurricane season last week. As I discussed in my post on their forecast, NOAA is calling for very active and possibly hyperactive season. They give an 85% chance of an above-normal season, a 10% chance of a near-normal season, and just a 5% chance of a below-normal season. NOAA predicts a 70% chance that there will be 14 - 23 named storms, 8 - 14 hurricanes, and 3 - 7 major hurricanes, with an Accumulated Cyclone Energy (ACE) in the 155% - 270% of normal range. If we take the midpoint of these numbers, NOAA is calling for 18.5 named storms, 11 hurricanes, 5 major hurricanes, and an ACE index 210% of normal. A season with an ACE index over 175% is considered "hyperactive."


Figure 2. Visible satellite image of Tropical Cyclone Phet on Thursday, June 3, 2010.

Tropical Cyclone Phet the 2nd strongest Arabian Sea storm on record
Record heat over southern Asia in May has helped heat up the Arabian Sea to 2°C above normal, and the exceptionally warm SSTs helped fuel Tropical Cyclone Phet into the second strongest tropical cyclone ever recorded in the Arabian Sea. Phet peaked at Category 4 strength with 145 mph winds yesterday, and has weakened slightly to 135 mph winds this morning. Only Category 5 Cyclone Gonu of 2007, which devastated Oman, was a stronger Arabian Sea cyclone.

Phet is over very warm waters of 30 - 31°C, and is under moderate wind shear of 10 - 20 knots. However, the storm is wrapping in dry air from the Arabian Peninsula, which has caused weakening. Visible satellite imagery from this morning (Figure 2) shows that the heavy thunderstorms on the north side of Phet have been eroded away by dry air. Phet is a small storm, and could fall apart fairly quickly if dry air can penetrate into its core. This should happen later today, since wind shear is on the increase, and the shearing winds should be able to disrupt the circulation enough that dry air can force its way into Phet's eyewall. Phet is fairly small, will miss the most heavily populated areas of Oman, and will likely undergo significant weakening before landfall, so the storm is unlikely to cause the kind of catastrophic flooding that Category 5 Cyclone Gonu of 2007 brought to Oman. Gonu killed 50 people and did $4.2 billion in damage. Phet's heaviest rains will be confined to a relatively sparsely populated region of Oman's coast. Rainfall amounts in excess of 6 inches in 18 hours (Figure 3) can be expected along Oman's coast today, which will likely cause extreme flooding.

After Phet's encounter with Oman, the storm will probably be at tropical storm strength when it makes its second landfall in Pakistan. Heavy rains from Phet will be the major danger for Pakistan, and serious flooding can be expected over southern Pakistan.


Figure 3. Forecast rain amounts for the 18-hour period ending at 2am EDT June 3, 2010. Image credit: NOAA/NESDIS.

Oil spill update
Onshore winds out of the south, southwest, or west are expected to blow over the northern Gulf of Mexico over most of the next week, resulting increased threats of oil to Alabama, Mississippi, and the Florida Panhandle, according to the latest trajectory forecasts from the State of Louisiana. The latest ocean current forecasts from the NOAA HYCOM model show that these winds will generate a 0.5 - 1 mph current flowing from west to east along the Florida Panhandle coast Sunday and Monday. If this current develops as predicted, it will be capable of bringing light amounts of oil as far east as Fort Walton Beach, Florida, by Monday. 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.

Oil spill resources
My post, What a hurricane would do the Deepwater Horizon oil spill
My post Wednesday with answers to some of the common questions I get about the 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
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
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

I'll be back Friday with an analysis of the new TSR hurricane forecast and a new forecast by a promising Florida State University model.

Jeff Masters

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Per msnbc.com:

"Even when the cap is in place, officials say it will be at least a day before they know if it works and oil will continue leaking into the Gulf of Mexico until relief wells are finished in August."
Member Since: Posts: Comments:
Quoting CaneWarning:


I just hope it actually makes its way to Tampa.
It will get the whole peninsula... have you seen the long range tampa radar? lol
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I realy think they just now need to hook up the new pipe to the new cap and "viola" done!
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1628. BtnTx
This may or may not be true: I heard an offshore oil expert talk today on a talk radio show. He said everything that BP is doing currently will not work and BP knows it. All current activity is just for Public Relations and Obama is in on the scam. This expert said nothing will work until the relief wells have been been drilled and put into service. This is expected to be done by Christmas 2010. I am no expert and this is just what I heard. I have no real knowledge about any of this and just thought I would pass it on.
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geez just look at it flow out from everywhere...
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Okay guys see that like yellow thing on the pipe, look to the left of it and oil is coming out there.
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
WOW, you can really see the oil coming out in stream2 right now.
Member Since: Septiembre 2, 2009 Posts: 130 Comments: 21194
Looks like the oil is just rerouted to the sides vs straight up. Hopefully, they have yet to hook suction up...I hope it's Dyson.
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1622. Patrap
I think we could have a Cat-1 to a Cat WD-40 if our luck holds..

Pffft..

This iz a bad 50's Horror Flick script.

Somethings gotta give soon..

And it dont have to be good Im sensing.
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Quoting Baltimorebirds:
Another fail to contain the leak means more loss of wildlife and nature not only that but the fishing men will also lose there livly hood of what they do.Some have the risk of losing thier jobs.Sigh.I feel so helpless.


Speaking of job losses, they say Pinellas County alone may lose 21,000 jobs due to the oil spill.
Member Since: Abril 26, 2009 Posts: 3 Comments: 3667
Quoting Hurricanes101:


When did he say that?


Post 1472.)
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
Quoting MrstormX:


No BP suddenly turned all the cameras away from the thing... literally 5 minutes after the cap failed.


No they didn't every feed is up working on my site.....except the one off line.....all 5 are working now.
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Good evening WU family. The Barometer Bob show tonight is awesome. Dr Gray is looking for a wild ATL Hurricane Season!!!
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Link

try this live cam
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What makes you think it failed
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Quoting MrstormX:


No BP suddenly turned all the cameras away from the thing... literally 5 minutes after the cap failed.


They don't want us to see their failure...or possible failure.
Member Since: Abril 26, 2009 Posts: 3 Comments: 3667
1613. Patrap
Oil Zilla continues to Lurk and grow in the Gulf,,what used to be our Gulf of Mexico.

Now its becoming a cesspool.

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Quoting MrstormX:


Yes levi says there is a possibility of development in the Southern GOM in like 64 hours. GFS verifies


When did he say that?
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it doesn't
really matter

at this point
the damage
is done

the gulf
is dead
Member Since: Posts: Comments:
Quoting all4hurricanes:
Are the models predicting any development within the next two weeks?


Yes levi says there is a possibility of development in the Southern GOM in like 64 hours. GFS verifies
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
Lets give them time......like i said maybe the suction has not started yet......give them time.
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Try this link

http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk_english/homepage/STAGING/local_assets /bp_homepage/html/rov_stream.html
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Are the models predicting any development within the next two weeks?
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Quoting aquak9:
can anyone see anything besides that stupid brain and brain stem that's floating around in the front?


No BP suddenly turned all the cameras away from the thing... literally 5 minutes after the cap failed.
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
This is not working.....it appears. ONLY If they keep pressure in the tube and then suddenly released it to suck would this had a chance.......OH NO
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1603. Ossqss
Patience, there is more at play than meets the Webcam. Remember, the try and try again principle.
Member Since: Junio 12, 2005 Posts: 6 Comments: 8186
lol, dang patrap you beat me to the lyrics...
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1601. aquak9
can anyone see anything besides that stupid brain and brain stem that's floating around in the front?
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Quoting louisianaboy444:
Ok i got an interesting but trivial question...Hurricane Audrey was first detected in the BOC as a tropical storm....could Audrey have been a Cross-over storm from the Eastern pacific?


Don't know if it was but this was a lot like her track 8 years earlier.



Texas just loves to share storms with or neighbors. Over n over n over That storm, Audrey, Rita...
Member Since: Agosto 15, 2008 Posts: 10 Comments: 3665
Quoting aquak9:
canewarning I am overly quite aware of the deaths involved- I have been screaming about this to co-workers since the damn thing caught on fire and everyone laughed at me

and ike don't feel bad cause we have all been hoping and feeling disappointed and like screaming


It's a disaster that's just getting worse. I feel like I'm watching a bad "end of world" movie.
Member Since: Abril 26, 2009 Posts: 3 Comments: 3667
Quoting MrstormX:


Yah the camera is pointed in a weird direction for some reason... maybe BP is turning away in shame.
They should.
Member Since: Septiembre 2, 2009 Posts: 130 Comments: 21194

Maybe they still have to hook a pipe at the top of the cap to pump the oil to a surface tanker. . . maybe that's why we are still haveing all that oil action. No suction yet. I hope it something like that.
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Quoting Baltimorebirds:
Where..where's the video to the leak??


http://tampaspinsweather.webs.com/oilspilllivevideofeed.htm
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Quoting MiamiHurricanes09:
Stream2 is the correct one, right?


Yah the camera is pointed in a weird direction for some reason... maybe BP is turning away in shame.
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
1594. pottery
Quoting Patrap:
I smell Hydrates and a clogged Up pipe

beginning to look that way
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1593. aquak9
canewarning I am overly quite aware of the deaths involved- I have been screaming about this to co-workers since the damn thing caught on fire and everyone laughed at me

and ike don't feel bad cause we have all been hoping and feeling disappointed and like screaming
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You mean you guys don't se the oil coming out the side...
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
1591. Patrap
.."Itsa crude, crude summer"..
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Quoting FLWeatherFreak91:
Very strong storms coming ashore in tarpon springs north.


I just hope it actually makes its way to Tampa.
Member Since: Abril 26, 2009 Posts: 3 Comments: 3667
you know this isn't rocket science...5000' under with around what 2600 psi? and to think something would just sit on top with no problems?? unreal....hell draw straws on the next idea i recon...
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Stream2 is the correct one, right?
Member Since: Septiembre 2, 2009 Posts: 130 Comments: 21194
Quoting IKE:


I hope you're right and I'm jumping the gun. If so, I apologize for my impatience.


Ditto.
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1585. Patrap
I smell Hydrates and a clogged Up pipe
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Taz its, "During active periods of hurricane season, these rules will be strictly enforced."
Member Since: Mayo 27, 2009 Posts: 0 Comments: 4438
live feeds

Link
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Quoting MrstormX:
Oil coming out of a new hole, farther down it appears....


Where? I only see the cap failing...
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Quoting MrstormX:


http://www.cnn.com/video/flashLive/live.html?stream=stream2
Thanks!!
Member Since: Septiembre 2, 2009 Posts: 130 Comments: 21194

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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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