A record quiet start to the 2010 Northern Hemisphere tropical cyclone season

By: Dr. Jeff Masters , 3:42 PM GMT on August 12, 2010

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The remnants of Tropical Depression Five have re-organized this morning, and the storm is pounding Southeast Louisiana with heavy rains. Radar imagery out of New Orleans shows that the remains of TD 5 have have formed some respectable low-level spiral bands that have brought heavy rains in excess of five inches in some areas. However, with the circulation center now moving over land, not much further development can occur.


Figure 1. Morning radar image of TD Five's remains.

Why so quiet in the Atlantic?
The Tropical Atlantic is quiet, and there are no threat areas to discuss today. The Invest 93 system we were tracking has been destroyed by dry air and wind shear. There are a couple of long-range threats suggested by some of the models--the GFS model predicts a tropical depression could form off the coast of Mississippi six days from now, and the NOGAPS model thinks something could get going in the Gulf of Mexico's Bay of Campeche seven days from now. Neither of these possibilities are worthy of concern at present. Overall, it's been a surprisingly quiet August, considering the pre-season predictions of a hyperactive season. According the National Hurricane Center, this hurricane season has been exactly average so far. There have been three named storms and one hurricane as of August 12. The average date of formation of the third named storm is August 13. One hurricane typically forms by August 10. One reason for this year's inactivity may be an unusual number of upper-level low pressure systems that have paraded across the tropical Atlantic. These lows, also called Tropical Upper Tropospheric Trough (TUTT) lows, tend to bring high wind shear that inhibits tropical cyclone formation. The other major factor appears to be that vertical instability has been unusually low in the Atlantic over the past month. Instability is measured as the difference in temperature between the surface and the top of the troposphere (the highest altitude that thunderstorm tops can penetrate to.) If the surface is very warm and the top of the troposphere is cold, an unstable atmosphere results, which helps to enhance thunderstorm updrafts and promote hurricane development. Since SSTs in the Atlantic are at record highs, enhancing instability, something else must be going on. Dry air can act to reduce instability, and it appears that an unusually dry atmosphere over the Atlantic this month is responsible for the lack of instability.


Figure 2. Vertical instability (in °C) over the Caribbean (left) and tropical Atlantic between the Lesser Antilles Islands and coast of Africa (right) in 2010. Normal instability is the black line, and this year's instability levels are in blue. The atmosphere became much more stable than normal in both regions at the end of July. This lack of instability also extends to the Gulf of Mexico and North Atlantic Ocean between Europe and North America, as well as the Western Pacific east of the Philippines, and the South Indian Ocean. Image credit: NOAA/CIRA.

A record quiet start to the 2010 tropical cyclone season in the Northern Hemisphere
What is really odd about this year, though, is the lack of tropical cyclone activity across the entire Northern Hemisphere. Usually, if one ocean basin is experiencing a quiet season, one of the other ocean basins is going bonkers. That is not the case this year. Over in the Eastern Pacific, there have been five named storms and two hurricanes. The average is seven named storms and four hurricanes for this point in the season. This year's quiet season is not too surprising, since there is a moderate La Niña event underway, and La Niña conditions usually supresses Eastern Pacific hurricane activity. But over in the Western Pacific, which usually generates more tropical cyclones than any ocean basin on Earth, it has been a near-record quiet season. Just four named storms have occurred in the West Pacific this year, and the average for this date is eleven. Only one typhoon season has had fewer named storms this late in the season--1998, with just three. The total number of named storms in the Northern Hemisphere thus far this year is fifteen, which is the fewest since reliable records began in 1948. Second place belongs to 1983 and 1957, with eighteen named storms. According to an email I received from NOAA hurricane researcher Gabe Vecchi, the lack of tropical cyclones so far this year in the Northern Hemisphere is between a 1-in-80 and 1-in-100 year event.

So, what is causing this quiet tropical cyclone season? One possibility is that since Northern Hemisphere land areas have heated up to record temperatures this summer, this has created strong rising motion over the continents. This rising motion must be compensated by strong sinking motion over the adjacent oceans in order to conserve mass. Sinking air causes drying and an increase in stability. Another possibility is that the unusual jet stream configuration that is responsible for the Russia heat wave and record flooding in Pakistan is also bringing dry, stable air to the Northern Hemisphere's tropical cyclone breeding grounds. It is also possible that climate change is causing the reduction in tropical cyclone activity, for a variety of complex reasons. Computer simulations of a future warmer climate generally show a reduction in global number of tropical cyclones (though the strongest storms get stronger), and it is possible we are seeing a preview of that future climate. Or, this year's quietness may simply be natural variability. It will be interesting to see when the Russian heat wave breaks if vertical instability over the Atlantic increases back to normal levels. Current forecasts from the GFS and ECMWF models project the Russian heat wave to break late next week.

Moscow's air remains clear; coolest temperatures in two weeks
Moscow's winds remained favorable for keeping smoke away from the city today, and temperatures "cooled" to at Moscow's Domodedovo airport to 33°C (91°F)--the lowest maximum temperature since a high of 32°C (90°F) was recorded on July 30. Moscow's airport has reached a maximum temperature of 30°C (86°F) or higher for 35 consecutive days now (at Moscow's official observing site, the Moscow Observatory, this string is 30 days.) Moscow's average high temperature for August 12 is 20°C (68°F). Moscow's high temperatures have averaged 15°C (27°F) above average so far this August--a truly extraordinary anomaly for a country so famous for its notorious cold weather. The latest forecast for Moscow calls for high temperatures of 30 - 33°C (86 - 91°F) Thursday through Monday. This is still 23°F above normal, but will be a welcome change from the extreme heat of the past two weeks. Long range forecasts from the ECMWF and GFS models continue to suggest that a series of troughs of low pressure will begin to attack the ridge of high pressure anchored over Russia beginning on Wednesday, bringing cooler temperatures just 5°C (8°F) above average to Russia late next week. By ten days from now, the ECMWF model shows a strong trough of low pressure over Moscow, and a end to the Great Russian Heat Wave of 2010.

Next update
I'll have an update Friday morning.

Jeff Masters

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Quoting RitaEvac:
Pat is your house haunted? 110 yrs old should have a lot of history



Only when I drink..
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Quoting CycloneUK:
Everyones always going on about GW but what about Antarctica!

Latest minimum temperature: -80.3C

lololololol


Antarctica is cold.

Shock, horror.
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Pat is your house haunted? 110 yrs old should have a lot of history
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387. There are a host of reasons why Haiti has been regressing as a country for the past half century. Too many to put on. One thing I believe is that there are far to many people living in Haiti for it to improve at its current state.
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410 I tend to agree with you, except the part about predicting which way the market will go. There are a lot of rich people on Wall Street. I'll bet they could show you a program that would explain exactly where your 401K money went.
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Quoting wdtcnewsonlinewx:
Have you guys noticed what the 12Z GFS is predicting 192 hours out?



Then look at it 288 hours out.



Quite far out, but very aggressive - will be interesting to watch
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Quoting StSimonsIslandGAGuy:
How's the rain where you are Patrap?

I think the lack of tropical activity in the western Pacific is remarkable. With the vast areas of warm water there, the atmosphere must be incredibly hostile to development now.


Light now with occasional Moderate at times.
The Gully washer was this morning between 4 and 7am



iVideo: Street flooding Uptown

Posted on August 12, 2010 at 8:12 AM

Street flooding at the intersection of State Street and Claiborne Avenue.
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Quoting btwntx08:
wow its a miracle ike show a model that has develop wow


Unnecessary... It would be a miracle if you used correct punctuation in a post though.
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Quoting Patrap:


.."I heard that and saw dat so you get a minus"..


I love shepards and miss mine.
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Hello all. I wanted to report on the conditions here in the greater New Orleans area. I was up drinking coffee at 5 a.m. when I thought the COC was coming through. Stormy then dead quite and still. Evidentialy this little rainstorm wants to live. Gusty winds to 28kts, bands of rain coming through. Just curious if anyone else has a thought on re-generation to something tropical in nature. BTW, I am no MET....I make a living in disaster management...therefor my handle. Have a great day and thanks for all of the insight and understanding I gain here.
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Quoting pottery:

Shucks, Cot.
You gone and spoiled my birthday...


My apologies, Pottery.

Being pedantic is just one of those persistent attributes... ;)
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Quoting gbreezegirl:
Yeah here comes the rain - thankfully cooling things off!

Raining heavy here now too.....
But then, it hasnt stopped in weeks really.
Member Since: October 24, 2005 Posts: 0 Comments: 24001
Have you guys noticed what the 12Z GFS is predicting 192 hours out?



Then look at it 288 hours out.

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ECMWF 12z 120 hours out showing the return of TD5 and the wave the GFS and CMC are showing.

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Quoting gordydunnot:
I could swear that was a big poodle.


.."I heard that and saw dat so you get a minus"..
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Everyones always going on about GW but what about Antarctica!

Latest minimum temperature: -80.3°C

lololololol
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Quoting RuBRNded:
Pensacola, get your umbrellas out. KATC radar.Link
Yeah here comes the rain - thankfully cooling things off!
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i might never overcome "me" blog addiction, smacks as it does of hilarity
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Quoting RitaEvac:
No time for partying Pat, stay away from windows and hunker down in the middle strongest part of the house. The eyewall is nearing you.


This Home is 110 years Old..so it can Huff and Puff with its 20 mph force and I doubt the Flowers will droop..

LOL
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Quoting Cotillion:


The storm on your birthday.

(The 'K' storm wasn't named until the day after, the 24th.)

Shucks, Cot.
You gone and spoiled my birthday...
Member Since: October 24, 2005 Posts: 0 Comments: 24001
I could swear that was a big poodle.
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Quoting SAINTHURRIFAN:
....this is not downcasting its present casting and at the present thier is no tropical system in the eastern atlantic.I know alot will disagree with this post just hope it gives some a little something to think about.
hurrifan, u boring, downcasting, realist, u.... lol

I don't think looking at a storm 2 weeks out is all that unrealistic at this point. The potential, climatologically, is certainly there. However, I do agree that this is definitely the time to engage in those enjoyable outdoor activities, to spend time with those loved ones who normally complain when u spend 20 of the 24 hours of the day tied to the computer, and to update storm preparedness for u and your family. We have at least 3 days before we can seriously expect something worth discussing to turn up.

Good to see u in the blog, BTW. I haven't been around ur last couple of turns in the blog...
Member Since: October 25, 2005 Posts: 19 Comments: 21432
Based on part of the content of blog attempting to explain the lack of cyclonic activity, I think it's apropriate to comment on golobal warming in general. The reality is that if we don't have either the computing power or software to predict financial activity, such as the behavior of the stock market, then what makes so many people so confidant that current software programs can predict what will happen in the next 100 years? All sorts of "authorities" predicted that this would be one of the busiest cyclone seasons ever (and it may still happen) but as Dr. Master's comments in today's blog suggest, there are no clear cut answers.
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Quoting Patrap:

Is the center trying to reform over the Chandeleur Islands?
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Quoting Patrap:


Door will be open to let in the Bloggers and rain cooled air.

Beware the Large German Shepherd though.

Yeah! I have heard that the LGS gets quite amorous after a few........
Member Since: October 24, 2005 Posts: 0 Comments: 24001
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No time for partying Pat, stay away from windows and hunker down in the middle strongest part of the house. The eyewall is nearing you.
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No thanks Pottery as some of my local friends would say Hell no dawg!!
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Quoting gordydunnot:
All right then Floodman party at Patrap's for the opening season game on, 6:30pm I hear.


Door will be open to let in the Bloggers and rain cooled air.

Beware the Large German Shepherd though.
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Quoting pottery:

Who ??


The storm on your birthday.

(The 'K' storm wasn't named until the day after, the 24th.)
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Quoting pottery:
Post 352, ElConando.
Very Sad, that report.
I feel so very impotent in the stuff going on in Haiti (as I am sure others do too).
The Scandal there, is the amount of $$$$ that is spent by the Aia Agencies in keeping thier staff there, living in pretty "ideal" conditions (comparitively) driving thier Prados etc etc.
It was interesting, after the Earthquake, that it was said that there were 2000 UN people there. 2000 staff. Doing WHAT exactly???
Haiti has been an easy rape for the "civilised" world, for a very long time.
That is not going to change in the near future.
Billions of $$$$ going in, and we all want to find ways to take it back out, is how it appears to me.

How is it possible to justify the vast sums of money put in there in the last 20 years, with NO apparent change in ANYTHING?


+1 Situations like this just astound me. For the amount of monies that have gone into this country, everyone there should be living quite comfortably. However, with no accountability, we see the sad reality. Truly shameful IMHO.

v/r

Jon
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All right then Floodman party at Patrap's for the opening season game on, 6:30pm I hear.
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Pensacola, get your umbrellas out. KATC radar.Link
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Quoting gordydunnot:
Well if we are all honest, in my opinion which one of us has never found traits or cultures that do not upset us. I always say please speak your mind or we can never learn if we are wrong.That being said what the hell could possibly wrong with the Irish. BYOB

Speaking as a person with strong Irish roots, you dont really want an answer to your question, do you?
heheheh
Member Since: October 24, 2005 Posts: 0 Comments: 24001
A Wunderground "Group Hug" moment is always satisfying.
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You guys have way too many Birminghams (methinks, on the whole, originality wasn't an Imperialist quality...).

Incidentally, the main American of note in the real Birmingham is in a bit of trouble right now.
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Thanks to Dr. Masters for saying exactly what I've said all summer. This year is SLOW. There is too much dry air and shear and will likely be one of the slowest years on RECORD
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Quoting Floodman:


**blushing** Gawrsh!

I love you too, Flood.

(it's Floodman appreciation day today)
Member Since: October 24, 2005 Posts: 0 Comments: 24001
Looks like TD5 may get another chance to become a named storm when is departs back into the GOM. The consensus among the models have this hooking back south.
Member Since: October 28, 2006 Posts: 57 Comments: 29885
Ill remember dat..

I have to get some Game Supplies in a Bit.



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Quoting ElConando:


Highs usually bring stability to the atmosphere so it is a good possibility it contributed greatly to it.
More specifically this season, the TC travelling on the edges of a very strong high is forced to go faster, right? Thereby making consolidation of storm circulation more difficult to achieve?
Member Since: October 25, 2005 Posts: 19 Comments: 21432
Quoting gordydunnot:
Well if we are all honest, in my opinion which one of us has never found traits or cultures that do not upset us. I always say please speak your mind or we can never learn if we are wrong.That being said what the hell could possibly wrong with the Irish. BYOB


There's nohting wrong with the Irish that a few stouts and wee bit o'Bushmills couldn't cure!
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Quoting Patrap:
Saints v New England 6:30 Pm on FOX


DA SAINTS are comming!
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Patrap when it gets calm there don't go outside for long the other side can catch you by surprise.
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Quoting Cotillion:


Tropical Storm Jose.

Who ??
Member Since: October 24, 2005 Posts: 0 Comments: 24001

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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.