TD 3 growing more organized

By: Dr. Jeff Masters , 8:01 PM GMT on July 22, 2010

Tropical Depression Three is steadily organizing, and appears poised to become a much stronger storm than was forecast. Water vapor satellite loops show that the upper level low to the west of TD 3 that has been bringing high levels of wind shear to the storm is now moving faster to the west than predicted. This faster motion has resulted in a reduction in wind shear over TD 3, to a moderate 10 knots. Satellite images of TD 3 show that the storm is taking advantage of the lower shear by developing several low-level spiral bands to the north and east of the center. However, the center of circulation is still exposed to view, and dry air is still getting injected into the core of the storm from the southwest. The storm's heavy thunderstorms have not increased in intensity this afternoon, and the amount of heavy thunderstorm activity near the core of the storm is still limited. TD 3 will need to build more intense thunderstorms near its center before significant intensification can occur. TD 3 is a small storm, and surface observations in the Bahamas do not show the circulation very well. An outer rain band of TD 3 is now visible on Miami long-range radar, and a flood watch has been issued for all of South Florida. The Hurricane Hunters are in the storm at present, and have found top surface winds of 35 - 40 mph.

Figure 1. Afternoon satellite image of TD 3.

Track Forecast for TD 3
The storm is in a straightforward steering current environment, and TD 3 should progress steadily to the west-northwest through Sunday. This will bring the storm ashore over the Florida Keys or South Florida on Friday, and into the Gulf of Mexico on Saturday. The latest set of model runs from 8am EDT (12Z) foresee a track more to the north than the previous set of model runs. This increases the threat to the oil spill region, and I give a 40% chance that the oil spill region will see tropical storm force winds of 39 mph or higher this weekend. Oil recovery and relief well drilling operations should cease. If TD 3 makes a direct hit on the oil spill region as a tropical storm with 50 - 60 mph winds, it will likely drive a storm surge of 3 - 6 feet with high waves on top into the Louisiana marshlands, fouling a large area with oil. Oil would also penetrate into Lake Pontchartrain, which lies just two feet above sea level. However, the wave action of the storm will dilute the oil to some degree, which may limit the damage to the marshlands.

If you are wondering about the specific probabilities of receiving tropical storm force winds at your location, I recommend the wind probability product from NHC. The latest 5 pm probabilities of various locations getting tropical storm force winds, 39 mph or higher:

Marathon 55%
Marco Island 43%
Miami 34%
New Orleans 33%
Galveston 13%

Intensity Forecast for TD 3
The primary detriment to development of TD 3 for the next three days will be the presence of the large upper-level low to its west. If the low remains in its present location, relative to TD 3, it will bring wind shear of about 10 knots to the storm. This will allow for steady intensification of perhaps 20 mph per day, and TD 3 could be a hurricane by Sunday at that pace. However, if the upper-level low slows down a bit, relative to TD 3, more shear and dry air will affect the storm, potentially weakening it. None of the computer models is calling for TD 3 to strengthen into a hurricane, but if the shear continues at 10 knots, I expect TD 3 will become a hurricane. My low-confidence intensity forecast gives TD 3 a 40% chance of becoming a hurricane. NHC is putting the odds of TD 3 being a hurricane at 2 pm Sunday at 15% with their 5pm advisory.

An area of disturbed weather (98L) has developed in the Gulf of Mexico's Bay of Campeche. This system is under a low amount of shear, 5 - 10 knots, and probably does not have enough time to organize into a tropical depression before making landfall along the Mexican coast a few hundred miles south of the Texas border on Friday.

Resources for the BP oil disaster
Map of oil spill location from the NOAA Satellite Services Division
My post, What a hurricane would do the Deepwater Horizon oil spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
NOAA's interactive mapping tool to overlay wind and ocean current forecasts, oil locations, etc.
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Next update
I'll have an update in the morning. ABC World News Tonight will probably show a sound bite I did for them today, on their 6:30pm broadcast.

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: 1319 - 1269

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 | 57Blog Index

Hi all...Well I am in SWLA and our Gov. just declared a State of Emergency....UGH!!
Member Since: Posts: Comments:
1318. GetReal
Hurricanes and Oil Slick

This is an official NOAA document...
Member Since: Posts: Comments:
Would the miami dade county take measures on halting public transportation if we just get bonnie in her current state?
Member Since: Posts: Comments:
1315. scott39
Quoting Patrap:
Which one of those have been the most accurate so far?
Member Since: Posts: Comments:
It's kinda hard to have a sense of humor when you have gone through something as bad as some of us have. I am not here looking for jokes I am looking for the comments of some of the most experienced people on here so that I may plan accordingly. I respect their information highly and am definitely not in a joking mood when it comes to the safety of my family...Thank you

Hey KatrinaBiloxiGirl,
Look with all due respect you should think about going into "Hurricane Mode" where you live.... We all know they seems to make that turn to the east right before landfall, and we will be on the worst side for the storm if it goes in to LA....
I have been here a long time and I just can't see anything stopping this from being a High end Cat1 maybe a Low end Cat2 at landfall....
So I just say be ready just in case..... I know I have been getting ready for 3 days now just to beat the rush of folks getting Gas, Batteries and can Goods....

We really never know where Bonnie will end up at the 2nd landfall....

Taco :o)
Member Since: Posts: Comments:
Hopefully admin bans hurrkat like they did debbykat and ALL of his other alias's.
Member Since: Posts: Comments:
Quoting hurrkat05:
you know another scenario could happen very easily...the ull could latch on the the tropical depression and continue to pull it westward towards the middle and upper texas coast...this is a very good possibility....

its not a tropical depression
Member Since: May 21, 2006 Posts: 5096 Comments: 117213
Quoting DestinJeff:

alphabetical rules apply

Member Since: July 8, 2005 Posts: 259 Comments: 25307
604 aspectre "TropicalDepressionThree was^heading for an AndrosIsland,Bahamas landfall in ~13hours on its way toward BocaRaton,Florida
(Straightline^projection using its last 2 positions. Take with HUGE grain of salt) [...more info...]"
642 sammywammybamy "Lol I live in Boca Raton, Florida. Doubt TD3 will make landfall here."

Got it in one. A straightline projection using a TropicalCyclone's last two reported center positions is less reliable for forecasting purposes than XTRAP*. The odds that a TC will not squiggle around in its travels closely approximates zero, so the odds of a straightline-projected landfall being accurate also nears zero.
About the only time its "fore"cast is somewhat reliable is less than 3hours before landfall... the timing of which we won't know until after landfall.

But it is interesting to compare with what the NHC reports as the TC's last heading and with the XTRAP projection.

* The eXTRAPolation model is not the same as projecting a straight line through the last two reported center positions. I believe it is the TC's various headings over the last 6to12hours averaged, then projected in a straight line from the TC's last reported center.

StormW? Weather456? SkyePony? Any of the others who know?
What the heck are the exact parameters defining XTRAP?
Read so many attempts at definitions here that I no longer remember the correct one.
(Don't know keywords that'll lead me to a glossary, so Google doesn't help).
Member Since: Posts: Comments:
Forget all the "HYPE" This is what is expected in case you
live in South Florida.

Member Since: July 3, 2007 Posts: 0 Comments: 524
Not bad down here just some needed rain.
Member Since: Posts: Comments:
i tihnk it may be a tad stronger
Member Since: May 21, 2006 Posts: 5096 Comments: 117213
went through Camille when I was 7 and everything up to and trough Katrina. And I come here to get professional opinions from SOME of the professionals here. No matter where it goes, God bless those in its path.

went through Camille when I was 7 and everything up to and trough Katrina. And I come here to get professional opinions from SOME of the professionals here. No matter where it goes, God bless those in its path.

You've got mail.
Member Since: Posts: Comments:
Troipcal Storm Bonnie
Tom Moore, Lead Meteorologist, The Weather Channel
Jul. 22, 2010 6:32 pm ET
Tropical Depression 3 has strengthened a bit and is now Tropical Storm Bonnie. Movement is to the northwest at 14 mph.
Tropical storm warnings remain is in effect for the Florida east coast from Golden Beach southward to the Florida Keys, and for the Florida west coast northward to Bonita Beach. The central and northwestern Bahamas are also under a tropical storm warning.
A tropical storm watch has been issued for the Florida east coast from Jupiter Inlet to Golden Beach, including Lake Okeechobee.
Tropical storm conditions are expected over the central and northwest Bahamas overnight and Friday. South Florida and the Keys should experience heavy rain and gusty winds on Friday. Rainfall amounts could exceed 5 inches in parts of southern Florida and the Bahamas.
Impacts on the oil spill in the northern Gulf of Mexico could begin Friday night and should reach their peak Saturday through early Sunday. Squalls with heavy rain and gusty winds and waves of 6-10 feet may develop by late Saturday and Saturday night.
A tropical low pressure system is getter better organized in the Bay of Campeche in the southern Gulf of Mexico. Thunderstorms continue to develop around the broad area of low pressure as it moves off toward the west between 10 and 15 mph. There is a window of opportunity for this system to develop into a tropical depression before it moves onto the central Mexico coast over the next 24-36 hours.
Heavy rain, flooding and mud slides are possible in central Mexico as the low moves through tonight and Friday.
Typhoon Chanthu made landfall in southern China near Zhanjiang early Thursday morning EDT. Winds were estimated to be near 85 mph as the typhoon moved on shore. The winds should quickly diminish now that the center is on land. Heavy rain and flooding are the main concerns in southern China and northern Vietnam as Chanthu moves farther inland.
Member Since: Posts: Comments:

Member Since: July 15, 2006 Posts: 193 Comments: 60433
Quoting hurrkat05:
why taz because everything i said was accurate...whats wrong with you..
I know I am not supposed to feed the monster, but I wanted to let you know your caps lock is off.
Member Since: Posts: Comments:
Hope no spent too much money on a shrine for the ECMWF, it totally missed Bonnie. Deeper reds starting to pop on on satellite, will be interesting to see if this is a sign of continued strengthening.

Member Since: July 8, 2005 Posts: 259 Comments: 25307
1290. Patrap
Member Since: July 3, 2005 Posts: 438 Comments: 136339
Thanks StormW have an enjoyable dinner
Member Since: Posts: Comments:
Quoting hurrkat05:
why taz because everything i said was accurate...whats wrong with you..

you been vary in accurate
Member Since: May 21, 2006 Posts: 5096 Comments: 117213
Quoting FLdewey:

Gee... I wonder which storm has scarred you for life? I'm an Andrew survivor, but that was a long time ago... house was lost, but sense of humor survived.

Look at this storm, read the NHC forecasts, and then read this blog. Do you see a reality gap? Most people come here to hear the worst, not the most accurate.
went through Camille when I was 7 and everything up to and trough Katrina. And I come here to get professional opinions from SOME of the professionals here. No matter where it goes, God bless those in its path.
Member Since: Posts: Comments:
1285. Patrap
Member Since: July 3, 2005 Posts: 438 Comments: 136339
Quoting hunkerdown:
you just now figured that out

The blog never had it to lose...
Member Since: Posts: Comments:
As the storm continues to develop and the hours pass, I'm becoming more and more concerned about flooding through South Florida tomorrow. Deep moisture associated with showers and storms due to Bonnie has become oriented across a large stretch from SE to NW and given the future motion shows a WNW track, this will push all that rain across the South Florida area. This has me most concerned right considering that we have seen well above normal rainfalls thus far this summer.
Member Since: Posts: Comments:
Quoting whs2012:

And Taz, ppl are on here all from the gulf coast trying to find answers about TS BONNIE. I think your pretty intelligent, why not try to give them answers. Debating over 98L isn't going to help least not on this blog.

ture but 98L dos looks a little way better the are TS
Member Since: May 21, 2006 Posts: 5096 Comments: 117213
1281. scott39
Quoting Levi32:

It means that south Florida still doesn't need to be concerned for anything more than weak tropical storm conditions, which is still a big deal but not a highly dangerous situation. Bonnie will probably weaken in the gulf and never become more than what she is now, a solid TS but on the low side.
If youve already explained this,then point me in the right direction, what is going to keep Bonnie a TS in the GOM?
Member Since: Posts: Comments:
98L is much more of a threat to life and property than Bonnie is right now. They have already had horrible flooding from Alex and TD2. Now up to 20 more inches on the way. There are also a lot of people from southern texas and mexico that frequent Dr. Masters blog who could be negatively impacted by the invest.
Member Since: Posts: Comments:
Winds are still up - light rain where I am - and delightfully cool for July... feels like autumn out there [well, autumn Bahamas style Lol].

I'm setting up my blog to give little updates on whatever tropical systems pass through the Bahamas and TCI.

I did promise MIAHur09 I'd do something this year.... lol
Member Since: Posts: Comments:
Quoting BahaHurican:
Evening again, all. The lead newscaster on our local station just got handed an email from the Met office detailing the upgrade of TD3 to Bonnie. It doesn't change a whole lot for us; winds hopefully won't get above 50 mph overnight, but pple were warned about flooding in lowlying areas. The met expects Bonnie to exit stage west tomorrow afternoon.

Hope it doesn't get too wild BAHA.
Member Since: Posts: Comments:
Don't leave.. just ignore the bloggers causing chaos. It truthfully, clears things out.
Member Since: July 8, 2005 Posts: 259 Comments: 25307
Quoting Hurricanes101:
This blog has lost it

Im out
you just now figured that out
Member Since: Posts: Comments:
Member Since: Posts: Comments:
1271. redUK

and somebody might listen to you
Member Since: Posts: Comments:
Quoting TropicalNonsense:

It's a 40 mph Tropical Storm near the Bahama's right now and
atleast a week away with alot of forecast uncertainty.

My question is how much additional money is the over reaction
costing the Tax payers again?
State of emergency's cost a great
deal ...not to criticize but it seems far to early and the storm may
end up in texas. The forecast accuracy is not good past 72 hours.

Of course it's an over reaction. If Jindal doesn't jump the gun and something bad happens then he gets criticized for it. Any guy with Presidential aspirations such as Jindal must CYA at all times.
Member Since: Posts: Comments:
1269. Patrap

Member Since: July 3, 2005 Posts: 438 Comments: 136339

Viewing: 1319 - 1269

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 | 57Blog Index

Top of Page

Dr. Jeff Masters' WunderBlog


Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

Local Weather

47 °F

JeffMasters's Recent Photos

Cedars Plastered by Snow
Snowstorm over Dunham Lake
Beech tree fall color in the U.P.
Altocumulus clouds over Pictured Rocks National Lakeshore beaver pond