Tropical Depression Two forms from Invest 98L

By: Dr. Jeff Masters , 9:33 PM GMT on July 17, 2011

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Tropical Depression Two (TD2) formed from Invest 98L this afternoon. Hurricane Hunters flew into the suspect area and found a surface circulation north of the Bahamas, with maximum sustained winds of 35 mph. They also determined the system had become warm core—a characteristic that must be present in order to declare a tropical cyclone. Satellite imagery continues to show the system is becoming more organized with a stronger circulation. Wind shear is forecast to remain favorable for the system until Tuesday or Wednesday when higher shear will slide in from the north. Sea surface temperatures are warm enough to sustain a tropical storm.


Figure 1. Satellite imagery of Tropical Depression Two in the Atlantic, east of Florida. This graphic will update to the current satellite imagery.


Figure 2. Official 5-day forecast for Tropical Depression Two. This graphic will remain current.

Forecast for TD2

The models are coming into better agreement as TD2 has become more organized. In terms of dynamical forecast models, the HWRF and GFS both forecast TD2 to max out just above tropical storm strenth. HWRF intensifies TD2 to around 47 mph in the next 24 hours, whereas GFS is a bit slower to bring the system up to tropical storm status. Two statistical models, the DSHP (SHIPS model that includes land interaction) and the LGEM (Logistical Growth Equation Model) both intensify TD2 to a moderate tropical storm over the next 2-3 days.

There tends to be a lot of uncertainty involved with tropical cyclones that form under these circumstances, but our forecast remains in line with the National Hurricane Center and the reliable forecast models. TD2 will move slowly to the northeast in weak steering currents over the next few days before eventually becoming an extratropical storm. There is minimal chance that this system will cross over Florida into the Gulf of Mexico. Timing and path depend heavily on how intense the cyclone gets, as Jeff mentioned in his blog earlier today. A weaker storm will tend to stay south, whereas a stronger storm will grow taller in the atmosphere and winds at higher levels will influence it and steer it northeast.

None of the reliable models predict tropical cyclone development over the remainder of the Atlantic through July 23.

Angela

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Quoting Skyepony:


July 21st


Thanks!
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Quoting presslord:
If Pat is around...When is the shuttle due to land? and...What might this mean to the prospects?
July 21, early morning I believe
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This is my company website with pics and area of operations for all our tugs.
http://www.dannmarinetowing.com/index.html

I’ll talk to some of the other Captains and see if they will contribute reports when possible this season, especially out of the tropics.

Now, since I will have no more relevant info until 2300, I will clear the board for those of you figuring out what Bret intends to do.
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422. Skyepony (Mod)
Quoting presslord:
If Pat is around...When is the shuttle due to land? and...What might this mean to the prospects?


July 21st
Member Since: August 10, 2005 Posts: 161 Comments: 37449
yah know, none of the models called this, so no one thought it would form. now the models point it off to the northeast. but most satellite show steering towards the west. definitely very interesting.

ive been watching this system since it was just a little swirl off SC. absolutely fascinating.
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420. JLPR2
The last tropical wave brought plenty of humidity with it.
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If Pat is around...When is the shuttle due to land? and...What might this mean to the prospects?
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Quoting MrstormX:
If anything this blog has died after the formation of Bret, guess everybody is sad it isn't going to hit Miami.


I'm not entirely convinced that the convection over Miami isn't being generated by Bret. And the vis loops appear to indicate the CoC is still moving towards FL. As someone said earlier, the models tend to overestimate troughs and underestimate ridges. In this case, I think we should place a little less faith in the dynamic models and a little more in the static models. IMO, it will be somewhere in the middle.
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Quoting ProgressivePulse:
It would appear to me that the outflow from the Tstorm complex over the peninsula did a number on Bret. Looking at satellite you can see a definite eastward deflection of Bret and a breakdown of what little convection there was in the Western Semi as a result.
What you're seeing is the higher level convection getting sheared east. The LLC is meandering.
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Quoting ProgressivePulse:


I am personally. This would have been perfect, weak TS to bust this drought. I am sure most of the state was wishcasting today.


We need rain in SoFla! A mild tropical storm would be welcome. Oh well, hope it does not hurt the Bahamas.
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The question is not whether the wind is blowing but what the wind is blowing...a little humor lol
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Bret is a burst of convection away from being right back on track in terms of organization.
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410. JRRP
now


euro
240h
Member Since: August 16, 2007 Posts: 0 Comments: 5482
Quoting MrstormX:


Thought the drought was diminished?


In spite of the recent rains, we're just keeping up with normal ATM. There is a 24" deficit we're sitting on.
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Quoting CybrTeddy:
Said about 8 hours ago then-98L would look like this, its to be expected. Though, not going to lie I wasn't expecting Bret this soon.


You sure called it, circulation is solid though. Dmax is probably going to work wonders.
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Said about 8 hours ago then-98L would look like this, its to be expected. Though, not going to lie I wasn't expecting Bret this soon.
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Quoting MrstormX:
If anything this blog has died after the formation of Bret, guess everybody is sad it isn't going to hit Miami.


LoL and the gulf casters dissappeared too I think...J/k
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Quoting ProgressivePulse:


I am personally. This would have been perfect, weak TS to bust this drought. I am sure most of the state was wishcasting today.


Thought the drought was diminished?
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Quoting MrstormX:
If anything this blog has died after the formation of Bret, guess everybody is sad it isn't going to hit Miami.


I am personally. This would have been perfect, weak TS to bust this drought. I am sure most of the state was wishcasting today.
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Quoting nrtiwlnvragn:


scholar.google.com is your friend. Here is one paper:

Link

Thank you for the response.
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To: emcf30

Nope. This is.

My tug
http://www.youtube.com/watch?v=dF3uhDXNqQQ
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If anything this blog has died after the formation of Bret, guess everybody is sad it isn't going to hit Miami.
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Now now boys...we all know that Janiel Francisco Vargas is from Hialeah... Don't tarnish the good name of Cuba!
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Quoting BahaHurican:
The blog didn't go wild at 8 p.m.??? lol

Most recent from NASA...



I agree was just thinking that the blog has slowed up quite a bit once the models started looking more like an out to sea storm and now it's looking a little more on the ragged side.
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Dry Air trying to invade it from the North West

Link
Member Since: July 22, 2010 Posts: 6 Comments: 752
Hey Tug is this you



Type of ship: Tug
IMO Number: 8201090 Flag: United States of America
MMSI Number: 367185680 Length: 30.0m
Callsign: WBI4636 Beam: 10.0m
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The blog didn't go wild at 8 p.m.??? lol

Most recent from NASA...

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Quoting NCCANE:
Again.. does anyone know the effect that the proximity to land has on the track of a T.S or Hurricane!


scholar.google.com is your friend. Here is one paper:

Link
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Quoting MississippiWx:
I think the best thing about TS Bret forming is the way it made The Weather Channel look stupid. Gave it no chance of forming earlier because no models supported it. That's forecasting at it's finest...

Oh, good evening, everyone!


+1,000,000,000
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It would appear to me that the outflow from the Tstorm complex over the peninsula did a number on Bret. Looking at satellite you can see a definite eastward deflection of Bret and a breakdown of what little convection there was in the Western Semi as a result.
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Quoting GeoffreyWPB:


Hi CaneVet...We might some good rains tomorrow, but that will be it.


I hope so, they'll be most welcome, for any of us in FL.
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I think the best thing about TS Bret forming is the way it made The Weather Channel look stupid. Gave it no chance of forming earlier because no models supported it. That's forecasting at it's finest...

Oh, good evening, everyone!
Member Since: July 15, 2006 Posts: 17 Comments: 10160
Quoting coastaltugcaptain:
Thanks to all you who are keeping your eyes on the weather. I have been at sea most of my life but I am not a weatherman. I take the info a weatherman gives me and make decisions based from there. I did suspect a disturbance from the persistent easterly swells but a suspicion was all it was. Anything I can do to help you will ultimately help me.

Thanks again.

P.S. If any of you use vessel tracking services, I am on the tug “East Coast” (not very imaginative is it?) with the barge “Penn 410”. I can also tell you, the majority of the mariners get there weather from this site. Thanks again.


Thanks for your upgate you gave earlier Tug. I am going to start to monitor your vessel. Good to have you aboard. Be Safe
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Anybody else wondering why there is no TS Warning in the Bahamas, it seriously looks like it might scrape a landfall there.
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Quoting GeoffreyWPB:
Anyone still think of a Fla. east coast crossing?


I have my eye on it. I wouldn't be surprised if it crosses near Miami. I think this because I believe we are working with a weaker system.
Member Since: July 22, 2010 Posts: 6 Comments: 752
Quoting aquak9:
The models did not have a GOOD starting point yesterday, last night, early today. The models are just computer runs, ok? I mean they are good, but they are only math, expressed visually.
As more accurate info becomes available (yes, from recon aka TheHurricaneHunters), then the MATH going into the computer gets better, and the results become more accurate.

Very simplified, yes.

Well said. Also, as Angela pointed out earlier, some of the ensemble members were showing development. It suggests that things had to come together just right for development to occur, and given the shear going on it is not clear that conditions are completely favorable for development even with a "B" name hung on it.
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Bret might not look too impressive on IR but there is still circulation when observed on Water Vapor. Ther ridge is whe is pushing it to the SE, and in my opinion as the Ridge keeps on pushing the chances of bret turning towards Florida in a westward motion is unlikely. My take is that it will eventually start moving to the NE as predicted by most of the models.
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Quoting coastaltugcaptain:
Thanks to all you who are keeping your eyes on the weather. I have been at sea most of my life but I am not a weatherman. I take the info a weatherman gives me and make decisions based from there. I did suspect a disturbance from the persistent easterly swells but a suspicion was all it was. Anything I can do to help you will ultimately help me.

Thanks again.

P.S. If any of you use vessel tracking services, I am on the tug “East Coast” (not very imaginative is it?) with the barge “Penn 410”. I can also tell you, the majority of the mariners get there weather from this site. Thanks again.
If you are getting your weather info there are several very good people on here to take heed of. Levi32, Drakoen, CCHS to name a few. Sorry to those I did not mention but it's not coming to me at the moment. I know and they know who they are. Your observations are appreciated. I have an acquaintance who lives on the island most of the time who is also a tug captain but I think out of NJ. Safe trip.
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Quoting Guaricandilla2011:
Arlene, a Mexico digger, Bret, a fisher, good God, this trend cannot continue for the remainder of the season, and God willing, it shall not.


Don't count Bret out just yet. He might head towards the Carolinas or Florida.
Quoting weathermanwannabe:


I cannot second guess the call from NHC, as I am sure they had data this afternoon to call a tropical storm based on wind speeds, but looking at this rapid deterioration at the moment, I am thinking we just wasted a "name" on this one...........


This is what I was saying too. I stated that I have been on this system's band wagon since last week but that the upgrade to a TS seemed to be a bit early to me. Now that doesn't mean that I didn't think that it would NOT become a TS but thought it would probably more likely be a bit later.

Yet this will all play into my June/July Forecast of 3-5 storms. One more for July and we will have the 3. I still am sticking to my forecasted 3 storms for this month. I think we might get them towards the end of the month.
Member Since: July 22, 2010 Posts: 6 Comments: 752
I'm starting to think the Bahamas might get a landfall if this goes any farther South.
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Quoting PSLFLCaneVet:


Good evening, Geoffrey. :)

I'm thinking, no.

It's very pleasant outside, tonight, but I don't see a westerly motion happening. It has been interesting, watching the wind shift and the clouds reacting to the low center spinning up.


Hi CaneVet...We might some good rains tomorrow, but that will be it.
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Quoting coastaltugcaptain:
Thanks to all you who are keeping your eyes on the weather. I have been at sea most of my life but I am not a weatherman. I take the info a weatherman gives me and make decisions based from there. I did suspect a disturbance from the persistent easterly swells but a suspicion was all it was. Anything I can do to help you will ultimately help me.

Thanks again.

P.S. If any of you use vessel tracking services, I am on the tug “East Coast” (not very imaginative is it?) with the barge “Penn 410”. I can also tell you, the majority of the mariners get there weather from this site. Thanks again.


Coastal,

Stay safe out there and check frequently for updates.
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Quoting weathermanwannabe:


I remember that Dude.....Ahh, the good old days on the Blog.... :)


Me to hope we can get some more info like that this year.

coastaltugcaptain good to have you on and hope to hear from you again have a nice trip.
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Quoting TXHolly:
Ok. I'm confused. Pretty much all of the models show Bret moving out to sea. But when I look at the radar, it looks like it's moving almost the direct opposite direction. It really looks like it wants to cross FL and into the GOM. Can someone explain this to me?


Not at all. No westerly componet at all. Bret will not enter the GOM.
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Quoting GeoffreyWPB:
Anyone still think of a Fla. east coast crossing?


Good evening, Geoffrey. :)

I'm thinking, no.

It's very pleasant outside, tonight, but I don't see a westerly motion happening. It has been interesting, watching the wind shift and the clouds reacting to the low center spinning up.
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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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