Season's first tropical depression forms

By: Dr. Jeff Masters , 3:43 PM GMT on May 28, 2009

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Nature is jumping the gun a bit this year, with the season's first tropical depression forming four days before the official start to hurricane season. The area of disturbed weather (91L) that we've been watching, about 250 miles east-northeast of Cape Hatteras, North Carolina, has developed enough heavy thunderstorm activity and spin to be classified as a tropical depression. QuikSCAT imagery from last night revealed a closed surface circulation, but top winds of only 20 - 25 mph. Satellite estimates (using a cloud pattern recognition method called the "Dvorak" technique) were saying this was a tropical depression this morning, though, so the NHC elected to upgrade the system.

The disturbance is over the relatively warm waters of the Gulf Stream (25°C) and has wind shear of 5 - 10 knots over it, and these conditions are marginally favorable for some slow development to occur until Friday, when the system will likely move over waters too cold to support intensification. TD One is not a threat to any land areas. I give the storm a 60% chance of becoming Tropical Storm Ana.


Figure 1. Latest satellite image of TD One.

Is the formation of TD One a harbinger of an active hurricane season?
Probably not. Early season storms occurring near the U.S. coast have not been shown to be correlated with an active main portion of hurricane season during August - October. However, the situation is different if we start getting June and July storms in the deep tropics between Africa and the Lesser Antilles Islands. This was the case last year, when the formation of Hurricane Bertha in the deep tropics in July presaged an active 2008 hurricane season. According to the Hurricane FAQ, "as shown in (Goldenberg 2000), if one looks only at the June-July Atlantic tropical storms and hurricanes occurring south of 22°N and east of 77°W (the eastern portion of the Main Development Region [MDR] for Atlantic hurricanes), there is a strong association with activity for the remainder of the year. According to the data from 1944-1999, total overall Atlantic activity for years that had a tropical storm or hurricane form in this region during June and July have been at least average and often times above average. So it could be said that a June/July storm in this region is pretty much a "sufficient" condition for a year to produce at least average activity."

Portlight.org offering relief to Florida flood victims
Tropical disturbance 90L dropped as much as two feet of rain over Northeastern Florida last week, causing severe flooding. In Volusia County, at least 1500 homes were damaged by the flooding, and many of these were in low-income housing projects where the residents did not have flood insurance. Portlight Strategies, Inc., is now working to assist in this area by providing durable medical equipment to the disabled, elderly, or injured that have lost equipment due to the flooding. Equipment will also be provided to local shelters and other organizations working with flood victims. To help out, visit the Portlight disaster relief blog..


Figure 2. Rainfall amounts over Florida for the two weeks ending on May 27, 2009. Images credit: NOAA.

Jeff Masters

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puny little thing,lol...it won't even wake up the fish....
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cool.
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Quoting CaneWarning:


I think the chats have a counter on them, just not the blog. Good idea though.



Well, the way I see it, a viewer counter would help expose how many folks see what you post.

It should help the questions and answers, be the best they can be.

A learning blog assistant if you will.

Bloggers, how do you feel ? This exists for you afterall!

L8R

Beell, love MP, so here is a precursor to the imminent season :-)

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450. beell
It's a WU tradition...

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THE DEPRESSION COULD BECOME A TROPICAL STORM TONIGHT OR
EARLY FRIDAY BEFORE IT MOVES OVER COLDER WATERS. THE SYSTEM IS
THEN EXPECTED TO WEAKEN OR DISSIPATE BY SATURDAY.

...SUMMARY OF 1100 PM AST INFORMATION...
LOCATION...38.1N 67.8W
MAXIMUM SUSTAINED WINDS...35 MPH
PRESENT MOVEMENT...EAST-NORTHEAST OR 70 DEGREES AT 16 MPH
MINIMUM CENTRAL PRESSURE...1006 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 AM AST.
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Quoting WPBHurricane05:


So true.

Like usual, looks like we have an interesting season ahead of us.
been an interesting pre season so far
Member Since: July 15, 2006 Posts: 175 Comments: 54858
Quoting BtnTx:

All I get is Led Zeppelin music, but I am too late for live show...


Ike would probably like that.
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They probably would have called it Ana if the blue box (the center of circulation) was under the darker colors. Link
Member Since: July 31, 2006 Posts: 56 Comments: 8112
Quoting KEEPEROFTHEGATE:
stanger things have happen WPB
there really is no rules where and when they can pop up


So true.

Like usual, looks like we have an interesting season ahead of us.
Member Since: July 31, 2006 Posts: 56 Comments: 8112
444. Skyepony (Mod)
Oss~ Ike was right..Plan of Day. Never saw them not have one, though I don't check every single day.

TD1 looked really elongated on the Quikscat
Member Since: August 10, 2005 Posts: 193 Comments: 38679
Tropical Storm Ana is forecasted to form 8 AM ET.
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stanger things have happen WPB
there really is no rules where and when they can pop up
Member Since: July 15, 2006 Posts: 175 Comments: 54858
Still a possible Ana.

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I'm just amazed we have a tropical depression this far north in May.
Member Since: July 31, 2006 Posts: 56 Comments: 8112
evening all
Member Since: July 15, 2006 Posts: 175 Comments: 54858
Most everyone waiting to copy and paste the 11:00 p.m. info.!
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Hello all - I am new to North Carolina and was wondering if there are any spotters/chasers in the Triangle area and where I can locate a map of the Outer Banks and Crystal Coast showing evacuation zones.

Thanks.
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Still TD 1 as of the 11pm.
Member Since: July 31, 2006 Posts: 56 Comments: 8112
Quoting Ossqss:
Admin-- Why does this blog not have a participation counter?

We could be amazed at the number of visitors at any given time. Just my take and indirect request (ª¿ª) ?


I think the chats have a counter on them, just not the blog. Good idea though.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Admin-- Why does this blog not have a participation counter?

We could be amazed at the number of visitors at any given time. Just my take and indirect request (ª¿ª) ?
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432. BtnTx
Thanks Patrap & StormJunkie will tune in shortly.
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Evening Btn, the rebroadcast is starting now...
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427. BtnTx
Quoting StormJunkie:
Eric Blake from the NHC is on the Barometer Bob show tonight.

They are discussing the forecast process.

All I get is Led Zeppelin music, but I am too late for live show...
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Quoting GeoffreyWPB:
A fish storm is one that will affect maritime interests only.


Thank you!
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Quoting BaltOCane:


Sorry, I know I'm a rookie at all this, but what is PHISH? I've been seeing it all day "fish storm" and such. Please fill me in...


It is the same as fish from what I can tell, except somebody decided to be cute and change it a bit.
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A fish storm is one that will affect maritime interests only.
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Quoting Patrap:
No system has met any criteria for TS upgrade in the Atlantic.

And If ANA did magically gain some Bones and did..who would even remember in 2 months?


Time is better spent preparing now ,than waiting for a PHISH to be named.


Sorry, I know I'm a rookie at all this, but what is PHISH? I've been seeing it all day "fish storm" and such. Please fill me in...
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Quoting Levi32:


That was the new QuikSCAT pass.


Thanks, that's why I asked. Many of the many that watch, don't know for sure :)



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Quoting Ossqss:


I think it was referenced we should have a new QuickSat reading shortly ? That should tell the story.



That is the newest quicksat pass.
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Quoting Ossqss:


I think it was referenced we should have a new QuickSat reading shortly ? That should tell the story.



That was the new QuikSCAT pass.
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LOL looks like nature isn't the only one jumping the gun this year ;D

I admit I'm one among others ;D

I'll be back at 11pm (actually 10 where I'm at)
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Quoting Drakoen:


The circulation really hasn't improved. Wouldn't be surprised if they just kept it at TD status.


I think it was referenced we should have a new QuickSat reading shortly ? That should tell the story.

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I just want to thank Portlight for coming to our area to help after the flooding.I am sure it is very much appreciated.I had alot of water around and getting close but nothing intruded into my house or job and I am very thankful of that but I drove around and saw the devastation and it was amazing to see first hand.Again Thank You!!!
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Quoting Drakoen:
01L High-Resolution Quicksat
TS winds are around the COC so we could have an upgrade, my opinion
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Quoting futuremet:


Because they want Bastard's forecast busted.


That too.
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Quoting Drakoen:
NHC is not saving anything. They have a plethora of names to use.


Indeed.
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Quoting Ossqss:


Drak, I got dizzy looking at that. Synopsis ?


And 410, you teach us everyday and don't stop or we will have to re-negotiate you contract !


The circulation really hasn't improved. Wouldn't be surprised if they just kept it at TD status.
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Quoting Drakoen:
01L High-Resolution Quicksat


Drak, I got dizzy looking at that. Synopsis ?


And 410, you teach us everyday and don't stop or we will have to re-negotiate your contract !
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Me a teacher?..well I did substitute for my High School once during a Teachers strike in 79.

But seriously,other than teach a few USMC armor classes and NBC training classes,..I have to say no.

Member Since: July 3, 2005 Posts: 426 Comments: 129093
Quoting Drakoen:
01L High-Resolution Quicksat


It still looks like a TD. I don't see anything there indicating anything more.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
No system has met any criteria for TS upgrade in the Atlantic.

And If ANA did magically gain some Bones and did..who would even remember in 2 months?


Time is better spent preparing now ,than waiting for a PHISH to be named.
Member Since: July 3, 2005 Posts: 426 Comments: 129093
Quoting Patrap:
The Dvorak Technique Explained

The Dvorak technique is a method using enhanced Infrared and/or visible satellite imagery to quantitatively estimate the intensity of a tropical system. Cloud patterns in satellite imagery normally show an indication of cyclogenesis before the storm reaches tropical storm intensity. Indications of continued development and/or weakening can also be found in the cloud features. Using these features, the pattern formed by the clouds of a tropical cyclone, expected systematic development, and a series of rules, an intensity analysis and forecast can be made. This information is then standardized into an intensity code.


Patrap are you, or have you ever been a school teacher or college professor? Cause you do provide the most educational links and info.

And that is why i love this blog. It's a constant education.

Thanks!
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The fact that some bloggers argued that 90L was not named because the forecasters were on vacation during the Memorial Day weekend...No words can describe.
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Quoting Thundercloud01221991:


I do not understand the saving names thing. They have unlimited names if it qualifies as a TS they should name it period


If it deserves a name it will be named.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting GeoffreyWPB:
Why are some of you so adamant at getting TD 1 named Ana? It’s like an obsession.


Because they want Bastard's forecast busted.
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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.