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Gabrielle Getting Ripped Apart, Now a Tropical Depression

By: Dr. Jeff Masters, 3:05 PM GMT on September 05, 2013

After a brief 12-hour life as a tropical storm, Gabrielle has weakened to a tropical depression as it moves northwest at 9 mph. Wind shear, dry air, and interaction with the rough terrain of Puerto Rico and a strong tropical disturbance to its northeast have significantly disrupted Gabrielle. The surface center of circulation is near the Mona Passage between Puerto Rico and the Dominican Republic, and is displaced about 150 miles to the west-southwest of the main area of heavy thunderstorms over the Virgin Islands, as seen on satellite loops. A strong tropical disturbance located about 300 miles to the northeast of Gabrielle pulled the mid-level circulation of Gabrielle into it, leaving the surface circulation behind. This tropical disturbance that helped pull Gabrielle apart is a threat to become a tropical depression on its own--NHC gave it a 20% chance of development in their 8 am EDT Thursday Tropical Weather Outlook. The disturbance is headed to the northwest into an area with high wind shear of 20 - 30 knots, so development is unlikely.

Heavy thunderstorms from Gabrielle dumped over two inches of rain over portions of the Virgin Islands and Southeast Puerto Rico as of 10 am AST Thursday. Heavy rains will continue today across Puerto Rico and the Virgin Islands, as seen on radar out of San Juan, Puerto Rico. Gabrielle did not generate any sustained winds of tropical storm force (39 mph) at any land stations.


Figure 1. Morning satellite image of Gabrielle showing the surface center displaced 150 miles to the west-southwest of the main heavy thunderstorms over the Virgin Islands.

Forecast for Gabrielle
Wind shear is expected to steadily increase as Gabrielle heads northwest over the next few days. The storm will also be encountering the high mountains of Puerto Rico and Hispaniola, which should act to further disrupt the circulation. The tropical disturbance to the northeast of Gabrielle will also act to pull it apart, and it appears likely that Gabrielle will dissipate by Friday morning, unless the surface center can reform underneath the heaviest thunderstorms 150 miles to the east-northeast of the surface center. Gabrielle or its remnants should begin heading to the north over the weekend, and may pass close to Bermuda next week.


Figure 2. Radar-estimated precipitation from Gabrielle as of 10:32 am AST September 5, 2013.

Elsewhere in the Atlantic
A tropical wave over the extreme Southwestern Gulf of Mexico's Bay of Campeche (Invest 99L) will move ashore on the Mexican coast near Tampico on Friday. Satellite images show that 99L has a moderate area of heavy thunderstorms that are slowly increasing in size and intensity. Wind shear is moderate and water temperatures are a warm 30°C, so 99L will likely show steady development until landfall on Friday. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day and 2-day odds of development at 30%. A hurricane hunter aircraft is scheduled to check out the disturbance Thursday afternoon.

A tropical wave in the Eastern Atlantic about 450 miles west-southwest of the Cape Verde Islands (Invest 98L) is headed west-northwest at about 10 mph. Satellite images show that 98L has a decent amount of spin, but a very limited amount of heavy thunderstorms. Wind shear is moderate and water temperatures are a warm 28°C, so 98L may show some slow development today and Friday. By Saturday, 98L will encounter drier and more stable air, and be over waters barely warm enough to support a tropical cyclone--26.5°C. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day and 2-day odds of development at 10%.

A strong tropical wave is predicted to emerge from the coast of Africa on Saturday, and the GFS model develops this wave into a tropical depression near the Cape Verde Islands by Monday. The storm is expected to track to the northwest into a region of ocean where very few tropical cyclones ever make the long crossing of the Atlantic Ocean to threaten North America. Both the GFS and European models predict that this system will develop into a hurricane next week. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day odds of development at 30%.

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting 1997. opal92nwf:

I know I got caught up in the moment when I wrote that, but I just wanted you to see what you thought.

It's all good...

Cool. :)
2002. Torito
Gabs just got took off the NHC website like 20 seconds ago.
Quoting 1984. OviedoWatcher:
Going by your 'member since' date, you wouldn't...

You do realize that a lot of people on here (including me) were following this blog for a long time with no account on WU and only recently got one. I started watching this blog in 2008...and joined last year
Quoting 1974. Naga5000:


I was addressing yours.

But since you brought it up, I'll repost this, your feedback is greatly appreciated.

"It might be helpful for you to think a bit more logically about the statement "I don't believe in AGW". Among scientists, what you call "AGW" is simply the net result of the following chain of concepts:
- Humans burn fossil fuels.
- Burning fossil fuels produces CO2 [currently ~9.5 Pg C per year].
- About half of that CO2 remains in the atmosphere [the "airborne fraction"].
- Adding CO2 to the atmosphere raises its concentration in the atmosphere [currently ~400 ppmv].
- CO2 in the atmosphere absorbs longwave infrared radiation.
- The earth's energy budget is determined by the balance between absorbed shortwave solar radiation minus emitted longwave infrared radiation.
- In the absence of positive or negative feedbacks, increasing the concentration of CO2 in the atmosphere reduces outgoing longwave radiation and raises the temperature by 1C per doubling.
- This pre-feedback climate sensitivity will be reduced by negative feedbacks and increased by positive feedbacks. It can only be reduced to ~0 if the net effect of all feedbacks is sufficiently negative to stabilize climate in the face of forcings.
- The record of past climate changes (e.g., glacial/interglacial cycles) shows that net feedbacks within the earth system are not sufficiently negative to prevent large swings in climate.

"Every one of these is well established, from chemistry or physics in the case of steps 2 through 8, or from the geosciences in steps 1 and 9. Add them all up and you have "AGW".

"So ... which specific part of the process do you "disbelieve"?"
I do not think the case has been made that the warming we have seen over the last 150 years or so is inconsistent with past natural variations.

Even the much ballyhooed new, improved hockey stick had a buried admission that spikes could have happened in the past, the data was just not granular enough to show such if it did happen.

And the previous hockey stick was smoothed out to pretend the Medieval Warm Period never existed.

And I also believe that most AGW proponents have a preconception towards human catastrophism that gives them an inherent bias towards believing in AGW.

In the meantime, I keep my carbon footprint small. I just sold my car because I don't use it any more. Take transit everywhere. Live in an efficiency. Keep the thermostat pretty cool in the winter.

So I am not looking for an excuse to be a carbon-spewing hog. Just looking at this from the scope of geological time, instead of human lifetimes, where my great-great grandfather lived in a much colder world.
2005. Torito
Quoting 2003. opal92nwf:

You do realize that a lot of people on here (including me) were following this blog for a long time with no account on WU and only recently got one. I started watching this blog in 2008...and joined last year


same, I started watching it after the 2009 hurricane season.
2006. Tygor
Pretty good start to the day. Lots of people ignored, including some decent contributors to the list usually. Where is all this moisture coming from for South Texas models? I'm not sure it's going to get up enough to affect my parts, but still interesting to see the QPF predicting upwards of 5".
2007. Patrap
Quoting 1998. luvtogolf:


Lot's of fancy words and numbers that mean nothing.


Yeah, NOAA is full of them too.

Global Climate Indicators

LOL

The Science of Climate Change, and Science overall, does not care what any single Human "believe's",

It just is.


JeffMasters has created a new entry.
Quoting 1998. luvtogolf:


Lot's of fancy words and numbers that mean nothing.

Why would you think that? Measurable, verifiable data are just 'fancy words and numbers'? What would you use instead?
.
Quoting 2003. opal92nwf:

You do realize that a lot of people on here (including me) were following this blog for a long time with no account on WU and only recently got one. I started watching this blog in 2008...and joined last year

Yeah. I see that a lot. Many pride themselves with the whole "join date" thing like it's "untouchable" or something. If admin took that feature away, those folks would fall apart since their persona and mindset is build heavily upon the fact that they think others are inferior to them because they "think" they been here longer.

To me, that's an insecurity among an individual that has to be worked out. Definitely nothing ANYONE should ever take personally!
2013. yoboi
Quoting 1772. Neapolitan:
Neither saying nor hinting at. I'm just stating that the term "extreme" doesn't just mean "much more than normal", but also "much less than normal". You know: flooding rains are one type of precipitation extreme, while deep droughts are another type. So while I'm not claiming that this year's incredible lack of tropical activity in the Atlantic is in any way tied to the GW-driven disruption in weather patterns we've seen affect other types of extreme weather, it's certainly far to early to claim--as JB continues to do--that there's absolutely no correlation whatsoever between the two. That's all...



Can I bookmark this statement for you????? then I can show it back to you everytime you create your pretty graphs showing "EXTREME" ice melt for one (1) year and then you blame that one (1) year event with AGW.....why must thoult talk with a 360 degree tongue???
Seasons will pass you by... I get up... I get down...

Waiting for cold front seasons
for surfing season...

Quoting 2012. SouthernIllinois:

Yeah. I see that a lot. Many pride themselves with the whole "join date" thing like it's "untouchable" or something. If admin took that feature away, those folks would fall apart since their persona and mindset is build heavily upon the fact that they think others are inferior to them because they "think" they been here longer.

To me, that's an insecurity among an individual that has to be worked out. Definitely nothing ANYONE should ever take personally!

Okay that was WAY TOO DEEP. Haha. Sorry but see I did it too. haha
Quoting 1989. TropicalAnalystwx13:
99L may have been a tropical depression at landfall.

"They waited to long".Titanic quaote.
Quoting 1986. RGVtropicalWx13:
Models that are predicting some type of development in the western gom in 5 days or so.
Link


I have good rain chances 6 out of the next 9 days in Austin, unheard of, so GGGGRRREEAAATT!!! Thank you.
2018. LafLA
Quoting 1998. luvtogolf:


Lot's of fancy words and numbers that mean nothing.


It is amazing what government grant money will get you...
2019. 19N81W
Quoting 1971. RitaEvac:
I remember that night, it was dead calm and misting and couldn't believe a storm was that close offshore to my east as it scooted by. Talk about a vort cane, that was ridiculous.



thats an eerie radar loop...
I'm just wondering if there is a Blog on this site to chat about AGW/ Climate Change????
If there is I do wish that you all would use it in stead of the main Blog..... Now I do know Dr Masters does use his Blog for the same but in all due respect does not try to attack anyone because they do not believe in it....

Now I know I for one do not believe in AGW nor Climate Change, and there is no one here that will change my mind.... It is my opinion that the current "Cycle" we are in has everything to do with hurricane season. Or the lack there of.... Like I said yesterday I am Very thankfull that we have not had anything as of yet and hope not to have anything else the rest of the Season.... I just think "This Blog sould be of Tropical or Weather in General"

TIA
Taco :o)
Quoting 1970. opal92nwf:

What if 98L pulls an Eloise, would that make you happy?



Somewhat, but TD is too weak XD
Quoting 1981. BVI:


Did you get any rain? we have been deluged here in Tortola, been pouring for about 48 hours, also some bad flooding in St Thomas in the USVI


Not much here. 1 inch for the last 48 hours. BUST
Quoting 1968. washingtonian115:
From CwG..

"Enjoy the early signs (and day-to-day volatility) of our transitional season…"

Sounds similar to what they said in 209 as well..Hmm.But I have my doubts about this winter being anything but spectacular...

I hope you get a nice cold winter up there in the mid-atl with all the snow you want. I would love to see some light frost this winter in SFla. Enough to make us talk and remember about but not enough to cause any crop damage.
2024. MahFL
Bit of a swirl north of PR.

Quoting 2023. 954FtLCane:

I hope you get a nice cold winter up there in the mid-atl with all the snow you want. I would love to see some light frost this winter in SFla. Enough to make us talk and remember about but not enough to cause any crop damage.
what ya don't want too go ice skating on lake O
I'm sorry, I just don't understand why we can't accept that GW is caused by a combination of both natural and, yes, human factors. There is absolutely no doubt that warming and cooling patterns are cyclical and have occurred long before human existence. However, I truly believe that human activities have increased the speed of these cycles! Industrialization has been occurring for over 200 years now, so for 200 years, we have released what essentially become foreign contaminants (I'm a WALL-E fan) into the atmosphere. If I recall, the melting of the sea ice in Glacier Bay over the past 300 years would support this!
Quoting 2026. ProphetessofDoom:
I'm sorry, I just don't understand why we can't accept that GW is caused by a combination of both natural and, yes, human factors. There is absolutely no doubt that warming and cooling patterns are cyclical and have occurred long before human existence. However, I truly believe that human activities have increased the speed of these cycles! Industrialization has been occurring for over 200 years now, so for 200 years, we have released what essentially become foreign contaminants (I'm a WALL-E fan) into the atmosphere. If I recall, the melting of the sea ice in Glacier Bay over the past 300 years would support this!


Stop making so much sense, some people here might not appreciate that and attack you! Seems this whole summer has been about GW on this blog instead of the tropics, such a shame.
nice swirl north of PR.
-_- Thanks to these storms I am soaking wet an umbrella is useless when it comes to Florida T-Storms.

Our first TD that won't make it to TS strength...
Quoting 2016. washingtonian115:
"They waited to long".Titanic quaote.
So, what's it going to be this time? Brazilian dry air? SAL, an issue with bad oscillation.....can't wait to see this one go POOF!!!!
people .. new blogs been up for hours ..
Quoting 2033. whitewabit:
people .. new blogs been up for hours ..


But wabit, it's FUN to post on old blogs.

*said in whiny voice*

:)