Dorian Makes a Short-Lived Comeback as a Tropical Depression

By: Dr. Jeff Masters , 3:37 PM GMT on August 03, 2013

Share this Blog
53
+

Like an annoying fly buzzing around your head that just won't go away, Dorian is back. Dorian began as a tropical wave that moved off the coast of Africa on July 22. Although initially given only a 10% of developing, Dorian surprised forecasters by becoming the 2nd farthest east-forming tropical storm for so early in the year on July 24. Dorian peaked in strength on July 25, when its top winds reached 60 mph. On July 26, Dorian encountered a dryer, more stable atmosphere, and the storm dissipated to a tropical wave on July 27. The remnants of Dorian continued tracking west-northwest, passing north of the Lesser Antilles Islands and into the Bahamas this week. Finally, at 5 AM EDT this Saturday morning, the remnants of Dorian reorganized enough to prompt the National Hurricane Center to upgrade Dorian's remnants to be Tropical Depression Dorian.


Figure 1. Morning satellite image of Tropical Depression Dorian, showing the surface circulation exposed to view as a naked swirl of low clouds, and a modest area of heavy thunderstorms well to the south of the center.

Dorian does not have long to live, due to high wind shear of 20 - 30 knots that has removed all of the storm's heavy thunderstorms far from the center, leaving the surface circulation exposed to view as a naked swirl of low clouds. With wind shear expected to rise even further this weekend, Dorian will likely be dead by Sunday, and get absorbed into the cold front lying off of the Southeast U.S. coast. Dorian is not a threat to any land areas.

Elsewhere in the Atlantic, none of the reliable computer models is predicting tropical cyclone formation over the coming week.


Video 1. With Discovery Channel's Shark Week approaching, Veronica of the web video series, "Fact or Fictional?" talks with me and a marine biologist about sharknadoes. Is it possible for a ferocious tornado to rip through Southern California, raining man eating sharks? My bit starts about halfway through the video.

Have a great weekend, everyone!

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Sign In or Register Sign In or Register

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: 193 - 143

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 | 33Blog Index

Quoting 170. sar2401:

He said "approaching 60,000", and the radar image attached to the post had echo tops of 55,000. Not quite 60,000, but still impressive for south Florida.



Actually, 61,000 and if you look closely at thunderstorm just to the west of Fort Lauderdale at over 70,000 feet.

Member Since: July 17, 2009 Posts: 71 Comments: 27403
Quoting 117. nigel20:

Hi 954! It should have been an hazy day in Jamaica, but not much at the moment. It seems as if the moisture plume from central America is helping to moderate the SAL outbreak at the moment.

Hey there Nigel, thanks for the info. I'm not sure if any of that moisture from the CA make it here though. We'll keep out fingers crossed. Enjoy your SAL-less afternoon hopefully.
Member Since: Posts: Comments:
Quoting 178. Grothar:
Strong thunder and lightning to our west.



Looks like it's on the way Gro
Member Since: Posts: Comments:
Quoting 182. Astrometeor:


Strong thunder?
Hey Astro...Its true, thunder does vary in decibels, as lighten varies in power.
Member Since: Posts: Comments:
Quoting Grothar:

See, that's what I hate about the rainbow. All that supposed "convection" it shows over Alabama does not exist. There's not even any clouds, let alone rain. I never know what the rainbow is seeing.
Member Since: Posts: Comments:
Short blog update on TD Dorian and TS Gil.
Member Since: Posts: Comments:
Quoting 167. NCHurricane2009:

The MLC I generally think of at 850 mb or 700 mb. So those 200 mb winds aren't going to steer it into the Gulf.

The way I picture this situation in my head is that surface winds are southerly and upper winds are northerly...so if you were able to journey upwards the southerly winds gradually slow and eventually reverse to northerly. So the surface cyclonic center will move faster to the north...the mid-level cyclonic center will move to the north but much slower....and the storm's former ventilating upper anticyclone will stay where it is.

With the cyclonic low-level structure (source of surface convergence) and upper-level anticyclonic structure (source of upper divergence) becoming vertically decoupled and heavily titled....this whole thing is simply going to collapse offshore of the southeastern US because you need the surface convergence/upper divergence to be vertically stacked for optimal development of any sort....


Could be starting already.
Member Since: Posts: Comments:
Quoting 161. ColdInFL:
When will the bad news end? It's getting harder to convince people of our cause.

Link


The bad news will end when you realize the "science" upon which you apparently base your joy or sadness is fraudulent at worst, and inaccurate at best. Nature has a way of proving junk science wrong. Science is best when its practitioners accept that being wrong is part of the process and keep searching. When anyone declares that "the science is settled", they are easily dismissed as frauds.
Member Since: Posts: Comments:
Quoting 177. Tropicsweatherpr:
The 2013 North Atlantic season is just starting to climb the mountain to the September 10th peak day. But so far the reliable models don't have big developments until the 19th. Will that change in next runs?

Late start to the peak?
Member Since: Posts: Comments:
AccuWeather.com ‏@accuweather 44s

Greensboro, N.C. 1978: First of 9 straight days w/ measurable rain during which time 6.68" fell. #wxhistory
Member Since: Posts: Comments:
Link my new blog about all three storms
Member Since: Posts: Comments:
Quoting 178. Grothar:
Strong thunder and lightning to our west.


Strong thunder?
Member Since: Posts: Comments:
Quoting 171. Tribucanes:
A big shout out to Emory, his handle is close to that. He worked with the NHC 2004-2005 on conference calls when there were storms. He said the NHC was wrong this morning, that the LLC had ejected Northward and he was very surprised they classified Dorian again. He called this hours before the NHC came out and said it. I was dubious seeing how good I thought Dorian was looking again and the fact the NHC was saying what they were. But turns out he was 100% right and the NHC had it wrong at the time. Not often you see that.

I was confounded too by the NHC this morning. They used an ASCAT pass from 0245Z as a 5 AM (0900Z) center fix. I have the satellite imagery on a blog post showing that the actual center was indeed ejecting off to the north...these satellite tools were available so they should have seen it if we could have....
Member Since: Posts: Comments:
Really windy with dark clouds in west broward, FL. Looks like it is about to let loose at any moment. strong gusts and lighting.
Member Since: Posts: Comments:
Quoting 170. sar2401:

He said "approaching 60,000", and the radar image attached to the post had echo tops of 55,000. Not quite 60,000, but still impressive for south Florida.


I was just curious where the image was from, since there seems to be a discrepancy between that image and the doppler radar estimates from Miami. That's all.
Member Since: Posts: Comments:
Strong thunder and lightning to our west.

Member Since: July 17, 2009 Posts: 71 Comments: 27403
The 2013 North Atlantic season is just starting to climb the mountain to the September 10th peak day. But so far the reliable models don't have big developments until the 19th. Will that change in next runs?

Member Since: April 29, 2009 Posts: 75 Comments: 15162
Quoting NCHurricane2009:

The MLC I generally think of at 850 mb or 700 mb. So those 200 mb winds aren't going to steer it into the Gulf.

The way I picture this situation in my head is that surface winds are southerly and upper winds are northerly...so if you were able to journey upwards the southerly winds gradually slow and eventually reverse to northerly. So the surface cyclonic center will move faster to the north...the mid-level cyclonic center will move to the north but much slower....and the storm's former ventilating upper anticyclone will stay where it is.

With the cyclonic low-level structure (source of surface convergence) and upper-level anticyclonic structure (source of upper divergence) becoming vertically decoupled and heavily titled....this whole thing is simply going to collapse offshore of the southeastern US because you need the surface convergence/upper divergence to be vertically stacked for optimal development of any sort....

Very cogent explanation. I'm not sure why the idea that this whole tings going to just die off is so hard to accept...well, I guess after almost 2 weeks, it seems like a semi-permanent feature, but nothing is coming across Florida into the Gulf. The easterly winds are against it and the air in the Gulf is much drier and more hostile to any system now than the environment that the bits and pieces of soon to be (again) ex-Dorian are facing.
Member Since: Posts: Comments:
175. VR46L
Quoting 173. Grothar:


Dorians Ashes are spread around the Atlantic now ..
Member Since: Posts: Comments:
I'd say that the Death Ridge has pretty firmly entrenched itself over Texas at the moment.

Member Since: Posts: Comments:


Convection firing on the southern part of the depression. hehehehe
Member Since: July 17, 2009 Posts: 71 Comments: 27403
Member Since: Posts: Comments:
A big shout out to Emory, his handle is close to that. He worked with the NHC 2004-2005 on conference calls when there were storms. He said the NHC was wrong this morning, that the LLC had ejected Northward and he was very surprised they classified Dorian again. He called this hours before the NHC came out and said it. I was dubious seeing how good I thought Dorian was looking again and the fact the NHC was saying what they were. But turns out he was 100% right and the NHC had it wrong at the time. Not often you see that.
Member Since: Posts: Comments:
Quoting Naga5000:


Where do you see 60,000 ft? Highest cloud tops I have seen are a little under 40,000 according to Miami Doppler.

He said "approaching 60,000", and the radar image attached to the post had echo tops of 55,000. Not quite 60,000, but still impressive for south Florida.
Member Since: Posts: Comments:
Quoting 145. GetReal:


There are some tops to t-storms reaching 60,000 feet!


Where do you see 60,000 ft? Highest cloud tops I have seen are a little under 40,000 according to Miami Doppler.
Member Since: Posts: Comments:
Quoting 152. flcanes:

Nope.
I am at my house, been cloudy all day here in (not so) sunny SFL. :(


Send it our way, it is too hot here!
Member Since: Posts: Comments:
Quoting 107. HurricaneHunterJoe:


Thank you....I looked at that loop...if the MLC follows those winds is the MLC going into the GOM as per those N and NE/E wind barbs? And perhaps that is what someone else mentioned about it following the BAMD model into gulf?

The MLC I generally think of at 850 mb or 700 mb. So those 200 mb winds aren't going to steer it into the Gulf.

The way I picture this situation in my head is that surface winds are southerly and upper winds are northerly...so if you were able to journey upwards the southerly winds gradually slow and eventually reverse to northerly. So the surface cyclonic center will move faster to the north...the mid-level cyclonic center will move to the north but much slower....and the storm's former ventilating upper anticyclone will stay where it is.

With the cyclonic low-level structure (source of surface convergence) and upper-level anticyclonic structure (source of upper divergence) becoming vertically decoupled and heavily titled....this whole thing is simply going to collapse offshore of the southeastern US because you need the surface convergence/upper divergence to be vertically stacked for optimal development of any sort....
Member Since: Posts: Comments:
Filling in the gaps 2013, here's a look at our PWS network in action.

Published on Aug 2, 2013

At Weather Underground, our mission is provide the most accurate weather information for everyone around the globe. Our PWS (Personal Weather Station) Network is made up of thousands of individual weather station owners who collect and send data to us, giving us more real-time weather data than any official station network.


Member Since: Posts: Comments:
Big dust cloud!
Member Since: Posts: Comments:
Quoting Astrometeor:


Not at this moment.


Nothing happening in SE AL except a few baby storms wandering around. It's very hazy though - maybe the SAL has made it to Alabama. :-) 93 degrees with a dewpoint of 73, which is is actually 2 degrees cooler than yesterday, when our dry "Not as Hot" front went through. Looks like it's now returning north as a warm front, which means more sauna-like conditions but a slightly better chance of rain. Amazing how fast last week's rains have dried out.
Member Since: Posts: Comments:
Quoting 161. ColdInFL:
When will the bad news end? It's getting harder to convince people of our cause.

Link


The Human collective is a complicated one.

And now with this ever increasing connectivity, the Hive Mind is not taking the BS from the Fossil Fuel Funded denial machine. Everything around you, now think about this carefully, is from Human thought. Everything save for the Natural World.

Now that we've become all we can be in a way, we have to evolve, or our current way of life,brought about by Human thought, will definitely destroy us all.

First of all, AGW/CLimate Change denialist don't matter, and they NEVER have.

People say we can't affect the Planet.

Well I beg to differ, as we have the complete and Final means of destruction 40,000 times over.

That's the approx number of Nuclear Warheads on the Planet currently.

We must evolve in a Mindful way.

Fractures are everywhere, we know things almost in real time that can tip the Balance in a day.

Hold close the thought of evolving.

If not, well, the future is warm, Dim,and short maybe.

Just food for "thought".
Member Since: Posts: Comments:
Member Since: Posts: Comments:
When will the bad news end? It's getting harder to convince people of our cause.

Link
Member Since: Posts: Comments:
Member Since: Posts: Comments:

Station Select

New Orleans, Mid-City
Patraps Station

Scattered Clouds
Temperature
95.1 °F
Feels Like 104 °F
Member Since: Posts: Comments:
Quoting 109. hydrus:
This is the best I can do right now, One can see the remnant low over S.W. Texas. The other low is over or near the Bahamas heading for Florida.

One at 240 near Florida must be low at roughly 30W and 16N.
Texas one?
Member Since: Posts: Comments:
151. Patrap 5:42 PM GMT on August 03, 2013 +0



Pretty neat, got my Furst Yellow alert from the Top banner.



I first thought it was some new type of spam!!!
Member Since: Posts: Comments:
Quoting 109. hydrus:
This is the best I can do right now, One can see the remnant low over S.W. Texas. The other low is over or near the Bahamas heading for Florida.

Gotcha.
Member Since: Posts: Comments:
Before I go, i might want to add that the GFS was making mid level lows. Nothing is indicated in the low levels.
Member Since: Posts: Comments:
j.b.model?
Member Since: Posts: Comments:
Quoting 147. sar2401:

Pretty big storms, especially considering how small and inconspicuous they look on radar. Are there any warnings out in south Florida on any of those?


Not at this moment.

Member Since: Posts: Comments:
Quoting 147. sar2401:

Pretty big storms, especially considering how small and inconspicuous they look on radar. Are there any warnings out in south Florida on any of those?

Nope.
I am at my house, been cloudy all day here in (not so) sunny SFL. :(
Member Since: Posts: Comments:
Pretty neat, got my Furst Yellow alert from the Top banner.


Orleans
Special Statement
Statement as of 12:25 PM CDT on August 03, 2013

... Hot muggy day expected across the region...

Today will be another hot Summer day during what has actually been a
somewhat cool Summer. Highs today will range from the lower to mid
90s but with a very humid airmass in place... heat index values
will range from 100 to 105 degrees in most places. Nearly all
reporting locations saw morning lows cool enough to not warrant
the issuance of a heat advisory. However... locations along the
southshore will have the potential to see heat index values touch
105 degrees... or even a degree or two higher for a few hours.
Please take precautions today and try to keep cool.

Drink lots of water... take breaks often in the shade or in the air
conditioning... wear light weight and light colored clothing... wear
sunscreen to avoid burning... and never leave a child or pet in the
car.
Member Since: Posts: Comments:
Special Weather Statement New Orleans Office:

Upper Jefferson


Special Statement


Statement as of 12:25 PM CDT on August 03, 2013



... Hot muggy day expected across the region...

Today will be another hot Summer day during what has actually been a
somewhat cool Summer. Highs today will range from the lower to mid
90s but with a very humid airmass in place... heat index values
will range from 100 to 105 degrees in most places. Nearly all
reporting locations saw morning lows cool enough to not warrant
the issuance of a heat advisory. However... locations along the
southshore will have the potential to see heat index values touch
105 degrees... or even a degree or two higher for a few hours.
Please take precautions today and try to keep cool.

Drink lots of water... take breaks often in the shade or in the air
conditioning... wear light weight and light colored clothing... wear
sunscreen to avoid burning... and never leave a child or pet in the
car.
Member Since: Posts: Comments:
Quoting prcane4you:
That was a long time ago.Things are different now.Everyone knows today more SAL less hurricanes.

The SAL is pretty weak in the central and eastern tropical Atlantic. The SAL was a lot worst in the 2010 hurricane season. We had very little activity up to late August, but the rest is history.
Member Since: Posts: Comments:
Quoting 146. sar2401:

Yes, the strength was slightly overdone. :-) It's kind of hard to give the GFS much credit considering the number of ghost lows it's created in the general area over the past 45 days. If you keep predicting something will happen long enough during hurricane season, it probably will.

LOL.
As of right now, I think development would favor the gulf this week and early next.
The rest of Basin would become EXTREMELY favorable beyond that.
Member Since: Posts: Comments:
Quoting GetReal:


There are some tops to t-storms reaching 60,000 feet!

Pretty big storms, especially considering how small and inconspicuous they look on radar. Are there any warnings out in south Florida on any of those?
Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
GFS from 10 days ago, not to bad on position, strength overdone.



Yes, the strength was slightly overdone. :-) It's kind of hard to give the GFS much credit considering the number of ghost lows it's created in the general area over the past 45 days. If you keep predicting something will happen long enough during hurricane season, it probably will.
Member Since: Posts: Comments:


There are some tops to t-storms reaching 60,000 feet!
Member Since: Posts: Comments:
Quoting 135. sar2401:

He's talking about the 10 day GFS, not what's happening right now.

Yes I know that

Quoting 137. prcane4you:
That was a long time ago.Things are different now.Everyone knows today more SAL less hurricanes.

Umm no not really

Member Since: June 13, 2009 Posts: 2 Comments: 12736
Member Since: Posts: Comments:

Viewing: 193 - 143

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 | 33Blog 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.

JeffMasters's Recent Photos

Carrot Nose in Danger
Deep Snow in Brookline, MA
Sunset at Fort DeSoto
New Years Day Sunset in Death Valley