Tropical Depression Six arrives

By: Dr. Jeff Masters , 5:14 PM GMT on August 22, 2010

Share this Blog
4
+

Tropical Storm Tropical Depression Six is here, but it will not be a threat to land for at least the next five days. Tropical Depression Six is a classic "Cape Verdes"-type storm common during the peak part of hurricane season. Cape Verdes-type storms are so named because they form from tropical waves that come off the coast of Africa and pass near the Cape Verdes Islands just west of Africa. Cape Verdes hurricanes are the largest and most dangerous types of hurricane in the Atlantic, since they spend a long time over water have and have of opportunity to reach full maturity. Tropical Depression Six has a ways to go before it becomes a hurricane, as the storm is embedded in a strong easterly flow of wind courtesy of the African Monsoon that is generating a moderately high 15 - 20 knots of wind shear. There is also a tropical disturbance to the northeast of TD 6 that is sucking away some moisture and is interfering with the storm's circulation. Sea Surface Temperatures (SSTs) are a warm 28°C, and the storm is embedded in a moist environment, so wind shear is the primary inhibiting factor for development. The strong east winds imparting the shear are keeping any heavy thunderstorms from developing on the east side of the center of circulation, which is exposed to view in satellite imagery (Figure 1.)


Figure 1. Afternoon satellite image of Tropical Depression Six.

Forecast for Tropical Depression Six
A ridge of high pressure will force Tropical Depression Six to the west-northwest for the next five days, and the system should increase its forward speed from its current 10 mph to 15 mph by Monday night. A powerful trough of low pressure over the mid-Atlantic Ocean will begin to pull Tropical Depression Six more to the northwest late this week, and the storm should pass well to the northeast of the Lesser Antilles Islands. It remains to be seen, however, it this trough will be strong enough to fully recurve Tropical Depression Six out to sea. The GFS predicts that Tropical Depression Six may pass close to Bermuda about eight days from now, and it is also possible that Tropical Depression Six could eventually hit the U.S. East Coast 9 - 15 days from now. However, we have no skill in making these sort of ultra-long range forecasts, and the long-range fate of TD 6 is uncertain.

Elsewhere in the tropics
The ECMWF and NOGAPS models are predicting formation of a tropical depression off the coast of Africa 3 - 4 days from now.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 2982 - 2932

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66Blog Index

Member Since: Posts: Comments:
2981. surfmom
Quoting stillwaiting:
Hmmmm,morning everyone, the aoi offshore tpa might begin to orgainize if sheer relaxes...,been watching it spin since yesterday


me too !!! very confused about it & I don't know how to frame an intelligent question LOL
Still, missed the post if you answered this yesterday
are the Tarpon running on our shoreline/Siesta Key now? have you seen any mean-finned ones?
Member Since: Posts: Comments:
2980. Scimet
It appears that Danielle will only be a threat to marine interests in the north central Atlantic. Anyone knows what the forecast models are saying about the new disturbance off the African coast and what possible track it might take? Perhaps it's too early to know whether the same troughs (that will steer Danielle northeast) will impact this disturbance.
Member Since: Posts: Comments:
2979. hercj
Quoting StormW:


Well, I can...model consensus...still ain't happened yet. It will or should, but not yet. And the GFS that everyone worships, had her taking the hard north at 40W earlier in the period...where is the storm now?

Senior, I have looked at this from 3 different satellite's and the best I can do is 275 - 280. Where is the COC?
Member Since: Posts: Comments:
I don't much at all. The only thing I can say is nobody is right all the time with forecasting these storms, not the mets, not the people here, and certainly not the general public. Heck, most of them are oblivious and that's NOT a good thing.
Member Since: Posts: Comments:
2977. smuldy
Quoting BobinTampa:
I would ask how many on here have more tools at their disposal and more knowledge than the NHC??

ok cool then we can save some money cancel JMs blog and the comments and just read what NHC posts. Jees. Do they know the most? Well even - Max Mayfield prolly. But does that mean we shouldnt ever debate and agree or dissent?
Member Since: Posts: Comments:
2976. IKE
Quoting StormW:


Well, I can...model consensus...still ain't happened yet. It will or should, but not yet. And the GFS that everyone worships, had her taking the hard north at 40W earlier in the period...where is the storm now?


The storm is close to where the NHC thought it was going to be at this time.

Here's the 36 hour forecast by the NHC issued at 5pm EDST Saturday....

36HR VT 23/0600Z 13.6N 38.2W 55 KT

Here's where it was.....

INITIAL 23/0900Z 14.8N 37.1W 50 KT
........

The NHC has a track well north and east of the islands. The NHC has a track east of Bermuda. Those are the most important things. No one is perfect on a forecast.

Member Since: June 9, 2005 Posts: 23 Comments: 37858
2975. ryang
Member Since: Posts: Comments:
2974. SeaMule
Quoting StormW:
I know I shouldn't, as I know everyone is entitled to their opinion on Doc's blog, but I have to ask...how many of you that come on here and just make blanket statements and like stirring the pot, REALLY know anything about tropical meteorology?



How many meteoroligists really know for sure where this storm is headed? I haven't seen the first "expert" forecast a path south of where the "experts" thought it was going. This blog might go the way of FLhurricane.com...where unless you are some "expert"...your opinions and guesses aren't wanted. You will never hear them say...
"I really don't understand why the storm is heading more west than we thought. Then we they see the storm doing something that wasn't anticipated, they pretend to have covered their bases. Truth of the matter...the mets aren't right all the time...and I hate to think I'd have to listen to only experts. I'll take a free for all forum anyday. some people are just full of themselves, I guess
Member Since: Posts: Comments:
Quoting StormW:


How about the same tools and same knowledge.


I would say that's probably a bit aggressive. NHC has a multi-million dollar budget. If you can do the same work as them out of your house, you should write Obama a letter. He's looking to cut budget.

And this isn't to bash you. I look forward to your posts. But the NHC bashing on here gets ridiculous sometimes. What is the NHC's motivation to put out incorrect information??
Member Since: Posts: Comments:
TS Danielle Update..Video Blog
Member Since: Posts: Comments:
Quoting StormW:


How about the same tools and same knowledge.


how about less tools and knowlege but great psychic powers.
Member Since: Posts: Comments:
Quoting BobinTampa:
I would ask how many on here have more tools at their disposal and more knowledge than the NHC??



I don't have what they have. Just my eyes and opinion. I could be completely wrong about where I see the center and how I think it's moving. But at least they let the under qualified like me make a complete fool of myself on this blog if I so choose. :)
Member Since: Posts: Comments:
Quoting CybrTeddy:
ECMWF is predicting the 10% off Africa will develop.


and be a fish

Member Since: Posts: Comments:
Quoting CybrTeddy:
ECMWF is predicting the 10% off Africa will develop.


GFS also develops this.


Member Since: Posts: Comments:
2966. 7544
morning all looks like our ts doent want to play the model game and is going further south and moving west as of this hour . will this make the next run in a shift to the west . and will this be trend . as danaile misses the first trof . and she stalls that would give time for the high to build in and move her more west ? tia enjoy your coffee
Member Since: Posts: Comments:
2965. scott39
Quoting StormW:
Here ya go...this is in my synopsis, which I'm still typing, but try this:

Now, notice 2 things. Look in between the ridge centers, at around 40W. That is one weakness. If you look over the NC/VA area, and the flow off the Mid Atlantic coast, that's another "weakness" Even though the predominate flow is westerly, the storm is still going to "feel" or "see" these weaknesses, and have a tendency to want to head for them...the way out of the tropics, so to speak. If you take the direction toward the first break in the ridge, between the ATL ridge, that's about 315-320. The direction toward the east coast weakness is about 290. The predominate flow Danielle is in is 270. Add the numbers and divide by 3.
round off to 290
Member Since: June 13, 2009 Posts: 0 Comments: 6728
2964. IKE
Quoting barotropic:
"I know I shouldn't, as I know everyone is entitled to their opinion on Doc's blog, but I have to ask...how many of you that come on here and just make blanket statements and like stirring the pot, REALLY know anything about tropical meteorology?"

Very good point. Thats why this year I have mostly lurked. While this board has some knowledgeable folks on it, most are wishcasters to the hilt. That is in the often times face of fact, they have a sign on their foreheads that says "Please come hit me, I want a hurricane so bad", we CAN make this happen attitude. I mean some of you on this board I know are laughing right now because what I am saying is so so true! Case in point, a model consensus on a hurricane pointing directly at south Florida. Many "knowledgable folks on this board take issue when someone suggests that the storm will miss south florida and as a matter of fact, actually get pissed off. Yet, the same scenario with a solid model consensus of a storm recurving, they take issue with those that may suggest that florida or the US is pretty much out of the woods. So even those with knowledge often times on this site are highly biased. As a matter of fact, I read this board for entertainment. If I want an opinion I can read the numerous discussions issued by the NWS and the TPC. Those discussions are arrived at after some of the sharpest minds in tropical meteorology have reviewed the facts, the models and than added the human factor and opinion. What more do you need?


I can't argue with anything you said and I read it 3 times. I agree with your comments.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting CybrTeddy:
ECMWF is predicting the 10% off Africa will develop.


Yeah I saw that. But I'm ignoring the thing in the GOM. For now. Looks familiar some how. :)
Member Since: Posts: Comments:
I see Danielle is organizing nicley.should be a hurricane by late tonight into tomorrow morning.And the wave off of africa could become a storm in the next few days.
Member Since: Posts: Comments:
Quoting StormW:
Here ya go...this is in my synopsis, which I'm still typing, but try this:

Now, notice 2 things. Look in between the ridge centers, at around 40W. That is one weakness. If you look over the NC/VA area, and the flow off the Mid Atlantic coast, that's another "weakness" Even though the predominate flow is westerly, the storm is still going to "feel" or "see" these weaknesses, and have a tendency to want to head for them...the way out of the tropics, so to speak. If you take the direction toward the first break in the ridge, between the ATL ridge, that's about 315-320. The direction toward the east coast weakness is about 290. The predominate flow Danielle is in is 270. Add the numbers and divide by 3.


Hi Storm,

You must be a mind reader as I was just about to post the image below. Danielle is about mid way the weakness between two bridging highs. That would account for where the system is now but as it progresses it will come under a stronger Westerly flow from the high to the West. This should flatten the track some and may already be influencing it.

Member Since: Posts: Comments:
Hmmmm,morning everyone, the aoi offshore tpa might begin to orgainize if sheer relaxes...,been watching it spin since yesterday
Member Since: Posts: Comments:
Quoting BobinTampa:
I would ask how many on here have more tools at their disposal and more knowledge than the NHC??





(Hand springs up into the air)


Pick me, pick me! I know this one!!!!
Member Since: Posts: Comments:
ECMWF is predicting the 10% off Africa will develop.
Member Since: Posts: Comments:
Quoting StormW:
Here ya go...this is in my synopsis, which I'm still typing, but try this:

Now, notice 2 things. Look in between the ridge centers, at around 40W. That is one weakness. If you look over the NC/VA area, and the flow off the Mid Atlantic coast, that's another "weakness" Even though the predominate flow is westerly, the storm is still going to "feel" or "see" these weaknesses, and have a tendency to want to head for them...the way out of the tropics, so to speak. If you take the direction toward the first break in the ridge, between the ATL ridge, that's about 315-320. The direction toward the east coast weakness is about 290. The predominate flow Danielle is in is 270. Add the numbers and divide by 3.


So bascially in the 291-293 range.
Member Since: Posts: Comments:
Quoting StormW:
Here ya go...this is in my synopsis, which I'm still typing, but try this:

Now, notice 2 things. Look in between the ridge centers, at around 40W. That is one weakness. If you look over the NC/VA area, and the flow off the Mid Atlantic coast, that's another "weakness" Even though the predominate flow is westerly, the storm is still going to "feel" or "see" these weaknesses, and have a tendency to want to head for them...the way out of the tropics, so to speak. If you take the direction toward the first break in the ridge, between the ATL ridge, that's about 315-320. The direction toward the east coast weakness is about 290. The predominate flow Danielle is in is 270. Add the numbers and divide by 3.


Now this makes sense. Thank you. I always learn from your posts.
Member Since: Posts: Comments:
I would ask how many on here have more tools at their disposal and more knowledge than the NHC??

Member Since: Posts: Comments:
To me it looks like she's moving just north of 14n and almost due west. With all the prior stated caveats to my credentials. :)
Member Since: Posts: Comments:
Quoting flstormhog:


Morning Storm,

Looks like the Left Ventricle is engorged. ;)


Congestive storm failure? ;)
Member Since: Posts: Comments:
Quoting gdnsetter:
My guess is very few know anything about tropical meteorology (including me). That is why I would like to see an "Accept" button. It would be just the opposite of the ignore button. It would allow me to create a list of bloggers whose posts I want to read. Everyone else would not be seen.

As it is now, I need to scroll thru pages and pages of posts to read yours and the posts of a few others whom I feel know what they are talking about.

Back to lurking.





Now THATS a good idea!!

+100
Member Since: Posts: Comments:
"I know I shouldn't, as I know everyone is entitled to their opinion on Doc's blog, but I have to ask...how many of you that come on here and just make blanket statements and like stirring the pot, REALLY know anything about tropical meteorology?"

Very good point. Thats why this year I have mostly lurked. While this board has some knowledgeable folks on it, most are wishcasters to the hilt. That is in the often times face of fact, they have a sign on their foreheads that says "Please come hit me, I want a hurricane so bad", we CAN make this happen attitude. I mean some of you on this board I know are laughing right now because what I am saying is so so true! Case in point, a model consensus on a hurricane pointing directly at south Florida. Many "knowledgable folks on this board take issue when someone suggests that the storm will miss south florida and as a matter of fact, actually get pissed off. Yet, the same scenario with a solid model consensus of a storm recurving, they take issue with those that may suggest that florida or the US is pretty much out of the woods. So even those with knowledge often times on this site are highly biased. As a matter of fact, I read this board for entertainment. If I want an opinion I can read the numerous discussions issued by the NWS and the TPC. Those discussions are arrived at after some of the sharpest minds in tropical meteorology have reviewed the facts, the models and than added the human factor and opinion. What more do you need?
Member Since: Posts: Comments:
2948. MahFL
The NHC always seems to far north or east, but invariably they end up correct. Both storms will likely miss Bermuda to the east.
Member Since: Posts: Comments:
2947. smuldy
Quoting kmanislander:
Good morning folks

Danielle is looking very good this morning and has built an impressive CDO.

I have been running the shorwave loop at various speeds and magnifications and from what I see the center does not appear to be as far East as the recent coordinates. I haven't looked at a microwave pass but 14.5 N and 38.5 W, or to the left of the points , is what I am seeing. It is entirely possible that the true center has relocated slightly and tucked a little deeper within the convection.

That would not be unusual for a sheared system that has reorganized.

In any event it is still far out at sea and a long way from any land so more of a " watch and see what happens " day today.
and right on cue everyone comes on lol; ok, good to see an advanced forecaster confirm what many on here were saying through the night about the center relocation
Member Since: Posts: Comments:
Quoting DestinJeff:
Should be a tad south of NHC track, but within cone. Hard to find center for me. I know the convection confuses me.


The shortwave is easiest for me to see. Link
Member Since: Posts: Comments:
2945. tkeith
Quoting sporteguy03:


Storm, there are people like yourself on here that take the time out of your day to answer questions, give forecasts and help share the power of knowledge to many people. I think that is a good thing right or wrong I appreciate the time and commitment people like you give to this blog.
I agree. And the same holds true for you too 03, and the others who take the time to help those of us with limited knowledge of the science invloved...

Having said that I dont mind being a litlte entertained at the same time.

As for the pot stirrers...unavoidable consequences of an open forum.

my 2 cents FWIW.



Member Since: Posts: Comments:
Quoting StormW:
I know I shouldn't, as I know everyone is entitled to their opinion on Doc's blog, but I have to ask...how many of you that come on here and just make blanket statements and like stirring the pot, REALLY know anything about tropical meteorology?
Hey Storm - I too am a novice when it comes to tropical meteorology (my expertise is in research medicine) but have been lurking on WU for many years now and have learned who I can trust for expert and credible information. I rarely add my 2 cents since there is a wealth of knowledge out there. It's a little funny (and frustrating) when I see some of these "hornet nest kickers" come up with these crazy forecasts and theories, but I just scroll right on through to the bloggers that I know have done their research.
Member Since: Posts: Comments:
Good morning folks

Danielle is looking very good this morning and has built an impressive CDO.

I have been running the shorwave loop at various speeds and magnifications and from what I see the center does not appear to be as far East as the recent coordinates. I haven't looked at a microwave pass but 14.5 N and 38.5 W, or to the left of the points , is what I am seeing. It is entirely possible that the true center has relocated slightly and tucked a little deeper within the convection.

That would not be unusual for a sheared system that has reorganized.

In any event it is still far out at sea and a long way from any land so more of a " watch and see what happens " day today.
Member Since: Posts: Comments:
so what Vero1 yes 900 utc but they are using 5 am data no diffrence
Member Since: Posts: Comments:
Good Morning everyone. While i am by far no expert. It seems to me that the NHC may be off on the center and direction of this storm. The center looks to be West of where the NHC says and the motion looks to be almost due west. Is anyone else seeing this?
Member Since: Posts: Comments:
2937. scott39
StormW, How far West will Danielle go if the first trough doesnt have an influence?
Member Since: June 13, 2009 Posts: 0 Comments: 6728
Quoting StormW:
Looks like a heart:


Morning Storm,

Looks like the Left Ventricle is engorged. ;)
Member Since: Posts: Comments:
Quoting scott39:
I dont have a whole lot of confidence in this first trough pulling on Danielle that much. Of course this is what im reading. Im not a forecaster. Hopefully they are right on the second Trough. We will see.


I agree. It looks like it is far south of the expected track to me. But I too hope it gets pulled out to sea before it harms anyone. This one looks like it's pretty healthy. Great for tracking. Awful for people.
Member Since: Posts: Comments:
2934. Vero1
TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT MON AUG 23 2010

...SPECIAL FEATURES...

AS OF 0900 UTC...TROPICAL STORM DANIELLE IS CENTERED NEAR 14.8N
37.1W...OR ABOUT 770 NM W OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MOVING NW AT 12 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 997
MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT.
FURTHER STRENGTHENING IS EXPECTED OVER THE NEXT 24 HOURS AND IT
COULD BECOME A HURRICANE BETWEEN MONDAY NIGHT AND TUESDAY
MORNING. CURRENTLY THE SYSTEM IS EMBEDDED WITHIN A LARGE AREA OF
ENHANCED DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER
IMAGERY. NUMEROUS STRONG CONVECTION IS MAINLY W OF THE CENTER
FROM 9N-17N BETWEEN 36W-42W. A TURN TOWARD THE WEST-NORTHWEST
WITH AN INCREASE IN FORWARD SPEED IS EXPECTED TODAY. SEE LATEST
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21
KNHC FOR MORE DETAILS.
Member Since: July 21, 2008 Posts: 4 Comments: 2233
Storm it looks like we could safely say that if weather was like Nascar, Danielle is paving the way knocking out the drier air with a train of waves drafting behin and ready to leave the African coast.

Lots of drier air now postioned into northern Africa.

Where is the MJB positioned? I can only imagine what should be a strong ridge of highs across the Atlantic when these waves leave the coast but I guess we shall see...
Member Since: Posts: Comments:
2932. Vero1
Member Since: July 21, 2008 Posts: 4 Comments: 2233

Viewing: 2982 - 2932

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66Blog Index

Top of Page

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.