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Tropical Storm Emily remains weak with roadblocks ahead

By: Dr. Jeff Masters, 6:14 PM GMT on August 02, 2011

Tropical Storm Emily took a moment to pause this morning, with no forward motion to speak of in the 11am EDT advisory from the National Hurricane Center, who say Emily might have been reorganizing. Emily eventually picked up some speed, and was moving west at 12 mph with maximum sustained winds of 45 mph in the 2pm EDT advisory. Satellite loops suggest that the storm has improved since yesterday, with strong thunderstorm activity surrounding the center of circulation accompanied by moderately strong outflow at higher levels. Recent satellite estimates of circulation show some consolidation at low levels (850mb), but weak circulation at higher levels (500mb). Despite the organized presentation on satellite, Hurricane Hunters found a generally disorganized storm this morning, with multiple potential centers. The lowest pressure that the Hunters found was 1007mb. Wind shear remains strong to the north of the storm, and this feature extends west across Puerto Rico and Hispaniola. Dry air, which has been lingering to the north of the system for the past few days, has begun to wrap around the northwest side of the storm. This, along with high wind shear along its potential track, could delay or prevent further intensification over the life of the storm. Another Hurricane Hunter mission is on its way to Emily now.


Figure 1. Visible satellite of Tropical Storm Emily at 1pm EDT.

Forecast for Tropical Storm Emily
The official forecast for Emily is a track toward the west-northwest over the next day and a half, after which it will make a turn to the northwest, and by Saturday, to the north. Although the National Hurricane Center has been shifting the forecast track to the east over the past few advisories, the U.S. coastline is still within the cone of uncertainty, and if we know something about this storm, it's that the forecast is uncertain. The CMC continues to be the western boundary of the model track forecasts, bringing Emily over Cuba and into the far eastern Gulf of Mexico. Today, on the eastern boundary of potential tracks fall the HWRF and the GFDL, which forecast Emily to cross over Hispaniola on a north-northwest trajectory, skirting the eastern edge of the Bahamas, and turning northeast before ever making connection with the U.S. coast. The Hurricane Center's official track follows the model consensus, and is the most likely track. Today, Emily is not forecast to strengthen into a hurricane within the next five days by the National Hurricane Center nor most of the models. Consensus seems to be that the storm will max out at a moderate to strong tropical cyclone, but this is assuming the storm can survive the wrath of Hispaniola.

Surviving Hispaniola

Hispaniola is somewhat notorious for being a major disruptor to tropical cyclones that dare cross over it. Since 1950, around two dozen tropical cyclones have crossed Hispaniola near where the National Hurricane Center is forecasting that Emily will pass over. A handful of these cyclones were of similar intensity with a track that was similar to Emily's forecast by various models, and although some went on to intensify (the warm Gulf of Mexico waters can be quite healing) many were fatally disrupted by the second largest island in the Caribbean.


Figure 2. Tropical cyclones that have crossed Hispaniola since 1950 (plotted using the NOAA Historical Hurricane Tracker).

Fay of 2008 developed in the Mona Passage on August 15th as a tropical storm. After a rough track westward over the length of Hispaniola, Fay emerged back into open water with little to no organized circulation, but managed to survive, and skirted the southern coast of Cuba for the next couple of days before turning north toward Florida. Many remember 2008's Fay as the storm that intensified and developed an eye-like feature over Florida after making landfall.

Cindy of 1993 was not as lucky in a battle with Hispaniola. Cindy developed as a tropical depression just east of the Lesser Antilles, and over the course of two days, tracked west-northwest through the Caribbean toward Hispaniola, strengthening into a tropical storm and reaching peak intensity just before landfall. Almost immediately upon landfall in the Dominican Republic, Tropical Storm Cindy deteriorated and the National Hurricane Center stopped issuing advisories on the system.

Emily of 1987 developed well east of the Lesser Antilles in late September and tracked northwest into the Caribbean, where it underwent a period of rapid intensification and was upgraded to a hurricane and then a major hurricane (category 3) just before landfall in the Dominican Republic. As the hurricane approached Hispaniola, it began deteriorating, and within 12 hours of landfall, Emily had weakened to a tropical storm and never regained its strength. Emily then took a turn to the northeast and tracked into the open Atlantic. Hurricane Katie of 1955 had a similar fate.

Angela

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 Ryuujin:
Did Emily's lower level circulation fall apart, or what is everyone talking about? I'm lost since I worked today.


2502. Patrap
2km Storm Relative IR Imagery with BD Enhancement Curve


Quoting Hurricanejer95:
*Double Facepalm* 91L all over again if recon finds it open...


they would not rename it the invest number
Quoting AbimaelPR:
Have we seen the worst for Puerto Rico???


We can expect bands arriving in the overnight hours with some gusty winds,mainly in the SW part of the island.
2505. JLPR2
Quoting FrankZapper:
What was that saying Dr Hope had about developing TS in the E Carib?


If a tropical disturbance doesn't develop before entering the Eastern Caribbean it wouldn't do so until reaching the Western Caribbean?
Quoting Tazmanian:


plzs dont start that
That's not what Dr Hope used to say.
2507. j2008
Quoting chevycanes:
radar out of PR really showing nice storms at the center now. looks like its spinning to me.

Thats what I thought, I trust radar more than ASCAT.
2508. Patrap
2509. JLPR2
Quoting Patrap:
2km Storm Relative IR Imagery with BD Enhancement Curve




If Emily's center relocates under the convection once again I will end up bald. XD LOL!
There is no way she has an opened surface circulation, convective cloud pattern hasn't looked better at all in her lifetime.
HH's should have really flown at 8 PM EDT instead of waiting till 2 AM EDT.
I honestly don't want to worry about this at the moment, so I think I will just go to bed, this system is strange I pray that Franklin behaves normally.
I'll wait for Recon before I make any conclusions. Although they may find a broad/elongated/ill-defined (lol) circulation, I doubt that the system has degenerated into an open wave.
05L/TS/E/CX
MARK
16.45N/65.63W
Quoting Hurricanes101:


they would not rename it the invest number
right they would say it open back up into a tropical wave, Hurricane Isidore did this after land interaction with Venezuela, but restrengthen back into a tropical depression just south of Jamaica.
Quoting JLPR2:


Considering convection is on the increase, Emily might close off her LLC by the time Recon takes-off.


That's certainly possible, but convection hasn't been a problem for Emily for a while now. She has a few issues that are keeping her from tightening the circulation.

One reason is that she remains decoupled from her mid-level circulation. The tilted structure is still causing competition between the low level circulation and mid level circulation.

Another reason is that she is simply fighting against the trade winds and probably a little resistance from South America. John Hope's rule was really not just a myth. There is a method to his madness. A tropical cyclone that is not well-established before entering the Eastern Caribbean will have these sorts of issues because of the speed of the trade winds and South America's land resistance. Emily will probably continue to struggle until she makes landfall in Haiti or around there. Land interaction might actually help her so that she can start anew with her circulation.
Quoting j2008:

Thats what I thought, I trust radar more than ASCAT.


Again radar does not depict the lower levels
XXL/AOI/XX
MARK NEAR
10N/37W
2519. Patrap
Typhoon Muifa


Threatening Okinawa



54 Hrs GFS stronger ridging.
2522. j2008
Quoting BrockBerlin:
I honestly don't want to worry about this at the moment, so I think I will just go to bed, this system is strange I pray that Franklin behaves normally.

Hope Franklin is a Cat 3 Fishstorm, just to prove to me that the Atlantic can still produce a Hurricane LOL.
I'm not really concerned about Emily per se...

At most I don't see her impacting the SE US as anything more than or strong TS or maybe a Cat. 1..

But what I am concerned about is the pattern that she is revealing to us:

A North Atlantic ridge situated farther south than normal, with its edge sitting just off the Southeast US Atlantic Coast. If this pattern holds for the season, or even just until mid-September, I think we most definitely will have a major hit somewhere on the US Atlantic coast.
Quoting thedawnawakening3:
There is no way she has an opened surface circulation, convective cloud pattern hasn't looked better at all in her lifetime.


that matters little if her surface circulation is weak, hers always has been, so I can easily see the notion that she has opened up
Would appear a due west motion with center due south of Puerto Rico?



Quoting Patrap:
2526. Patrap
San Juan Radar
NEXRAD RadarType
Velocity Azimuth Display Wind Profile ° Elevation

Quoting IceCoast:
54 Hrs GFS stronger ridging.
gonna be alot closer to florida
2528. Patrap
Relative motion seems w to wnw @ 13-14
Quoting SavannahStorm:
I'm not really concerned about Emily per se...

At most I don't see her impacting the SE US as anything more than or strong TS or maybe a Cat. 1..

But what I am concerned about is that pattern that she is revealing to us:

A North Atlantic ridge situated farther south than normal, with its edge sitting just off the Southeast US Atlantic Coast. If this pattern holds for the season, or even just until mid-September, I think we most definitely will have a major hit somewhere on the US Atlantic coast.
That is concerning for the east coast I think, since it also doesn't seem the Texas Ridge is breaking down anytime soon.
I'm thinking left of guidance. So much easterly motion
Quoting IceCoast:
54 Hrs GFS stronger ridging.
~ a more westerly path??
2532. Patrap
Quoting JLPR2:


If a tropical disturbance doesn't develop before entering the Eastern Caribbean it wouldn't do so until reaching the Western Caribbean?
Thank you JLPR2!
Taz poof
Quoting MiamiHurricanes09:
I'll wait for Recon before I make any conclusions. Although they may find a broad/elongated/ill-defined (lol) circulation, I doubt that the system has degenerated into an open wave.

I agree
2536. sdswwwe
New blog.
Quoting KEEPEROFTHEGATE:
XXL/AOI/XX
MARK NEAR
10N/37W


That CATL wave looks decent. Think NHC declares 92L soon?
Quoting Bluestorm5:
Learning about hurricane here... I guess I picked the wrong storm to be the first lesson for me. What is ASCAT?


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The global wind images display the available data from the previous 22 hours up to the image creation time. Click here for the ocean surface winds from the near real-time (NRT) observation data.

For additional information about the EUMETSAT METOP or ASCAT programs, please visit the EUMETSAT Polar System (EPS).
2539. emguy
Storms without established cores and/or are de-coupled systems typically move through similar 24 hours cycles like a broken record. This one is no exception. Once again, Emily decoupled again today. Last night, we thought the center was hanging back and it was kinda doing that through a low level reformation cycle that followed the decouple. Today into tonight...same story. Puerto Rico Radar would indicate a reformation/restack. It's a system yes, but a fragile and unestablished one at that.
Drifting westwards:

NEW BLOG!!!
Quoting thedawnawakening3:
There is no way she has an opened surface circulation, convective cloud pattern hasn't looked better at all in her lifetime.


The problem is that her surface center is not in the middle of that cloud mass at the moment. Your statement that the cloud pattern hasn't looked better is actually not true. She has done these flare-ups of convection for the last two days, only for them to wane and then re-fire. That is the ultimate clue that her circulation is not well defined. A strong low level center will continuously fire up convection, not have this pulsing pattern that Emily has.

Things can change rapidly and she could get her act together anytime. However, her looks are still deceiving, I'm afraid.
Anyone notice the 1008MB LOW in the central atlantic,any model consensus or thoughts on this?
2544. xcool
new blogggggggggg
Quoting MiamiHurricanes09:
Drifting westwards:

Look at the highs over the GOM, squeeze play or maybe Emily gets trapped, I see a High over the Northeast?
I say Emily is moving west it weak(stuck at 50/60mph)maybe less and I think the COC is not where the NHC puts it we will have to wait for the HH fly in to really know
Quoting emguy:
Storms without established cores and/or are de-coupled systems typically move through similar 24 hours cycles like a broken record. This one is no exception. Once again, Emily decoupled again today. Last night, we thought the center was hanging back and it was kinda doing that through a low level reformation cycle that followed the decouple. Today into tonight...same story. Puerto Rico Radar would indicate a reformation/restack. It's a system yes, but a fragile and unestablished one at that.


Well done!
Quoting ProgressivePulse:



Well, people in Florida will have less than 24hrs to prepare once Emily emerges back into water and the state of the storm is evaluated. Central Bahama's will have less time.
Tomorrow is the day to do stuff here. But a lot of people won't realize that until Thursday...

BTW, the apostrophe is not needed in Bahamas. The word is plural as in the specific islands, or singular as in the name of the country. Either way, no punctuation necessary... [why do I feel like press while doing this.... lol]
Quoting SavannahStorm:


That HWRF track has David all over it...



Except David went inland over SC. Emily may make a pass at every state on the South Atlantic! Talk about buzzing the tower!



It would be very interesting if we went back atmospherically to '78-79 tropical manifestations.
2550. Seawall
How many Jasons to delete? This is absurd. And not to be insensitive to anyone that has problems, but how do we know from a photograph that this young man has the symptoms, or whatever that has been suggested from Aspergers, or anything else? I'm sorry, but I've seen nothing to suggest he's anything but playing everyone off sympathy.
do you think Tropical Storm Emily will die out some when its land on wednesday
2552. DFWjc
Quoting jasoniswildman77:
do you think Tropical Storm Emily will die out some when its land on wednesday


No
low of 1008 mb!!
2554. DFWjc
Quoting jasoniswildman77:


and your point?
2556. wxhatt
Latest Recon Data for Surface winds:

SFMR Peak (10s) Sfc. Wind: 31 knots (~ 35.6 mph)

From only the edge of the storm.
Obvious naked swirl barreling west on vis sat loop. FL is going to get hit.... by a naked swirl.