Leslie headed towards Bermuda; Tropical Storm Michael forms

By: Dr. Jeff Masters , 3:01 PM GMT on September 04, 2012

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Tropical Storm Leslie continues to suffer from moderately high wind shear of 15 - 20 knots, due to strong upper-level winds out of the northwest. The shear is keeping heavy thunderstorms confined to the southeast quadrant of the storm. Satellite loops show that Leslie has almost no heavy thunderstorm activity near its center, and the storm is crawling north at walking pace, 3 mph. Leslie's slow forward speed means that the storm is staying over the cold water stirred up by the storm's winds, inhibiting intensification. According to the latest SHIPS model forecast, the shear is expected to stay moderately high through Tuesday night, then drop to the low category, 5 - 10 knots, by Thursday afternoon. At that time, Leslie will be over warm ocean waters of 29 - 30°C, and the reduction in shear and warm waters should aid intensification. However, Leslie's motion will continue to be slow, keeping the storm over its cool water wake, and keeping any intensification slow. Once Leslie begins moving more quickly on Saturday, this effect will diminish, and Leslie could be at Category 2 strength on Sunday morning, as indicated in the official NHC forecast. Steering currents for Leslie are expected to be weak through Friday, as Leslie is stuck between two upper level lows. The latest guidance from our top computer models continues to show Leslie making a very close pass by Bermuda on Saturday. Leslie is a huge storm, and tropical storm-force winds are expected to extend outward from its center 250 miles by Friday. Bermuda is likely to see a 48-hour period of tropical storm-force winds beginning Friday night that lasts until Sunday night. The official NHC forecast shows Leslie nearly making a direct hit on Bermuda, but the uncertainty in 4-day NHC forecasts is around 200 miles. Thus, the latest 11 am EDT NHC wind probability forecast calls for just a 12% chance of hurricane force winds on Bermuda on Saturday. Nevertheless, Leslie is capable of bringing an extended period of hurricane-force winds lasting six or more hours to Bermuda Saturday night through Sunday morning, should a direct hit materialize.


Figure 1. Morning satellite image of Tropical Storm Leslie. The low-level circulation center has very little in the way of heavy thunderstorms surrounding it, thanks to strong northwest winds creating 15 - 20 knots of wind shear.

Leslie will stay stuck in a weak steering current environment until a strong trough of low pressure approaches the U.S. East Coast on Saturday. This trough should be strong enough to pull Leslie quickly to the north on Saturday and Sunday, and Leslie may be close enough to the coast that the storm will make landfall in Nova Scotia or Newfoundland, Canada on Monday, September 10. None of the reliable models have shown that a direct hit on New England will occur, but we can't rule that possibility out yet. The storm may also miss land entirely, and brush by the coasts of Nova Scotia and Newfoundland. Large swells from Leslie reached Cape Hatteras, North Carolina last night, and will begin pounding the entire Eastern Seaboard today through Sunday. These waves will be capable of causing significant beach erosion and dangerous rip currents. The Hurricane Hunters are scheduled to make their first flight into Leslie on Wednesday afternoon.


Figure 2. Morning satellite image of Tropical Storm Michael.

Tropical Storm Michael forms in the Central Atlantic
Tropical Storm Michael has formed in the Central Atlantic on Monday, but is not destined for fame. Satellite loops show that this is a very small tropical cyclone, and the storm is well away from any land areas. Michael is under moderately high shear of 15 - 20 knots, and this shear is forecast to remain at 15 - 20 knots through Wednesday. Since Michael is such a small storm, just a modest increase in shear could destroy it. But if Michael survives until Thursday, when shear is expected to fall to the low range, it has the opportunity to strengthen.

Michaels's formation on September 4 puts 2012 in third place for earliest formation date of the season's thirteenth storm. The record is held jointly by 2005, which had Hurricane Maria form on September 2, and 2011, which had Tropical Storm Lee form on September 2 (there was an unnamed tropical storm that year before Lee.) None of the models show that Michael will threaten any land areas. Michael is a classic example of the type of storm that likely would have been missed before the advent of satellites, since the storm is small, far from land, and may be short-lived.

Jeff Masters

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Quoting MississippiWx:


Link


Thanks. It will be interesting to see what this stuff really is (it obviously doesn't look good visually.) I haven't been able to find any other news on this story as of yet.
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Quoting BrickellBreeze:
Issac is heading back into the Gulf...

some models have it tampa bound or just north of tampa..we will see in a few days
Member Since: August 6, 2011 Posts: 4 Comments: 38500



What is left of the center of Isaac????
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Issac is heading back into the Gulf...

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sure looks like rotation, but it could be just the radar sweep
Member Since: August 6, 2011 Posts: 4 Comments: 38500
oh lord
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Quoting StormHype:


Please reference source. This is FB image and I'm sure there are people falling for the urban hoax chain letters already.


Link
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Quoting scottsvb:


That's good news... more of that to wash ashore..the better for the water and we can clean it up easier


The problem is that it's still out there and not all of it is going to wash ashore. The chemicals they put into the water were supposed to get rid of it, but it apparently did not work if this is truly oil.
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Forecast intensities for Leslie on closest approach to Bermuda.

model raw / adjusted

12z GFDL 965mb / 964mb
12z HWRF 960mb / 968mb
12z GFS 974mb / 964mb
00z Euro 928mb / 923mb

avg raw: 956mb
avg adj: 955mb

without Euro:

avg raw: 966mb
avg adj: 965mb

Will be updated soon with the new Euro.
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Grothar is shirley a sciency blobologist
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Quoting MississippiWx:
Bad news. (Possible) Oil has resurfaced thanks to Isaac. This picture is from an Alabama beach.



Please reference source. This is FB image and I'm sure there are people falling for the urban hoax chain letters already.
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Quoting jascott1967:


I saw what you did there. You added a happy face at the end of an insult as if it were a comment condom.
"Insult"? Really? Instead of a hit-and-run job, can you please share with the class where I insulted the OP? Before you answer, remember: telling the verifiable truth in an objective way isn't an insult.

Thanks!
Member Since: November 8, 2009 Posts: 4 Comments: 13531
Quoting pottery:

You meant Blobologist, Shirley ?
.......hmmm sciencey,bloboligist? LOL...we had too much time off huh LOL
Member Since: August 6, 2011 Posts: 4 Comments: 38500
Quoting MississippiWx:
Bad news. (Possible) Oil has resurfaced thanks to Isaac. This picture is from an Alabama beach.

Ouch... glad to see you alright after Isaac.
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HAHA..
you changed it, but TOO LATE !

heheheheheh
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Member Since: August 6, 2011 Posts: 4 Comments: 38500
Quoting Bielle:

"Blobologist", surely!

You meant Blobologist, Shirley ?
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Quoting MississippiWx:
Bad news. Oil has resurfaced thanks to Isaac. This picture is from an Alabama beach.



That's good news... more of that to wash ashore..the better for the water and we can clean it up easier
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Quoting K8eCane:


certified card carrying

"Blobologist", surely!
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Quoting MississippiWx:
Bad news. Oil has resurfaced thanks to Isaac. This picture is from an Alabama beach.


AAAACCKKK !!

That's Bad.
Sorry to see that.
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Quoting jascott1967:
The knoweldge, or lack thereof of the word you may or may not find offensive (depending on if you were joking or being serious) is a reason for the unexpected/unplanned for children that may be viewing this blog.
I dislike having my dialog reduced to the lowest common denominator set by the presence of children, but actually the presence of children on this blog is not unplanned at all. It is expected that elementary-school-age children are reading and oftentimes participating on this blog.
Member Since: September 16, 2005 Posts: 0 Comments: 3167
Bad news. (Possible) Oil has resurfaced thanks to Isaac. This picture is from an Alabama beach.

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BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOBILE AL
1140 AM CDT TUE SEP 4 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
WESTERN BUTLER COUNTY IN SOUTH CENTRAL ALABAMA...
NORTHERN CONECUH COUNTY IN SOUTH CENTRAL ALABAMA...
NORTHEASTERN MONROE COUNTY IN SOUTH CENTRAL ALABAMA...

* UNTIL 230 PM CDT

* AT 1130 AM CDT...VERY HEAVY RAINFALL IS EXPECTED TO PERSIST ACROSS
THE WARNED AREA THROUGH EARLY THIS AFTERNOON. RADAR ESTIMATES THAT
2 TO 4 INCHES OF RAIN HAS OCCURRED OVER PORTIONS OF THE WARNED
AREA...WITH EVEN HIGHER TOTALS OVER EXTREME NORTHWEST BUTLER
COUNTY. ADDITIONAL RAINFALL ACCUMULATIONS OF 1 TO 2 INCHES PER
HOUR WILL LEAD TO THE LIKELIHOOD OF FLASH FLOODING IN THE WARNED
AREA.

* LOCATIONS IMPACTED INCLUDE...
MCKENZIE... I65 AND CR 7... I65 AND AL 106...
GEORGIANA... BEATRICE... I65 AND CR 29...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS FLOODING IS IMMINENT OR OCCURRING. SEEK
HIGHER GROUND IMMEDIATELY. DO NOT DRIVE OR WALK INTO AREAS WHERE
WATER CROSSES A ROAD. TURN AROUND - DON'T DROWN!

IF YOU ARE IN DANGER FROM THE FLOOD WATERS AND NEED RESCUE ASSISTANCE
CALL 911. TO REPORT FLOODING TO THE NATIONAL WEATHER SERVICE CALL
(800) 284-9059.
Member Since: August 6, 2011 Posts: 4 Comments: 38500
Michael up to 45 knots:

AL, 13, 2012090418, , BEST, 0, 273N, 436W, 45, 1006, TS, 34, NEQ, 30, 30, 20, 30, 1016, 140, 15, 0, 0, L, 0, , 0, 0, MICHAEL, M,
Member Since: November 8, 2009 Posts: 4 Comments: 13531
Quoting LargoFl:
Grothar is our certified Bloboligist


certified card carrying
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Quoting K8eCane:



Grothar writes BLOB but he has been allowed. The NHC copied it from Grothar yesterday
Grothar is our certified Bloboligist
Member Since: August 6, 2011 Posts: 4 Comments: 38500
Quoting jascott1967:


If Patrap can write "blob" I should be allowed "sciencey".



I am not going to argue with you about it, I happen to agree.
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Quoting jascott1967:


If Patrap can write "blob" I should be allowed "sciencey".



Grothar writes BLOB but he has been allowed. The NHC copied it from Grothar yesterday
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Quoting yqt1001:
I finally gave in to the smartphone craze and got a Samsung S3. Crazy how insane technology is!

Sorry for the off topic post. : P
I just purchased a 4g iPad two days ago.... Gotta say there is no better way to view satellite images than on a retina display. The resolution is amazing.
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Quoting TomballTXPride:

I see you got your sense of humor back bud! so glad don't want to upset you and glad your are having a fun time now....


Hahaha thanks for the concern LOL! FYI I never lost it and it would take a lot more than the likes of yourself to do it, so rest assured, bud :)
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.....................what are the chances this does NOT go all the way down to tampa, but crosses florida in the same path as Debby? flooding those people out once again?
Member Since: August 6, 2011 Posts: 4 Comments: 38500
Quoting OceanMoan:



More sciencey?? I love that reason!!!!


If Patrap can write "blob" I should be allowed "sciencey".
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Member Since: August 6, 2011 Posts: 4 Comments: 38500
I see the ECMWF is running late again. Also, if that system in the GOM develops will it retain the name Isaac or will it get a new name?
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Quoting Tropicsweatherpr:


Dont forget Jeanne in 2004 that was almost a hurricane when it crossed PR.
Jeanne felt  stronger than Irene but both were TS when they passed over us.
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Member Since: August 6, 2011 Posts: 4 Comments: 38500
Quoting guygee:

Well the argument for direct solar forcing has certainly been rebuffed by nature, as has the "cosmic ray-cloud nuclei" theory.


Clearly.


yet even I have pointed out that it is possible, however unlikely, that the Sun emits an unknown particle or wavelength that interacts with the earth and is undetectable to our instruments (too small/long of a wavelength, etc).

The probability of this is very low, but the only way I could think of testing for it would be abnormal bottom-heating of soils and bodies of water.

As far as I know, there are no such events being detected on a significant level, as this would need to be producing an effect equal to several ten-thousands of volcanoes in order to explain the observed oceanic warming. This would be painfully obvious to military vessels and research vessels who's instruments would have detected this by now.



I figure no more than a few hundredths of a percent of the net forcing could be coming from fluctuations in unknown particle or wave streams, else it would be recognized even if it couldn't be detected directly...
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Quoting jascott1967:


Yet we give them human names.

Personally I would prefer naming them after the date they are designated. Ex. 9192012; if 2 are designated on the same date 9192012-A and 9192012-B. More sciencey.



More sciencey?? I love that reason!!!!
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Quoting jascott1967:


Yet we give them human names.

Personally I would prefer naming them after the date they are designated. Ex. 9192012; if 2 are designated on the same date 9192012-A and 9192012-B. More sciencey.


I think people pay more attention to storms named like people, but that's my opinion. It is easier to refer to them the way my mind works. If you can believe what you see on the Internet, this history is interesting: "The pioneering Australian weatherman Clement Wragge began assigning names to tropical cyclones in the late 19th century, initially using the letters of the Greek alphabet and characters from Greek and Roman mythology. An eccentric and playful fellow, he later turned to the names of local politicians he particularly disliked; as a result, he was able to state in public forecasts that the officials were “causing great distress” or “wandering aimlessly about the Pacific.” Needless to say, Wragge’s subtly hostile approach didn’t take the meteorology profession by storm."

Link
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Quoting JLPR2:


El Nino will form, but it seems it will be later and weaker than forecast and it seems to be turning into a Modiki style one.



That's unfortunate because I believe moderate El Nino years bring cooler temps and wetter winters in Texas than weak El Nino.

Can anyone verify?
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192. auburn (Mod)
Quoting jascott1967:


Yet we give them human names.

Personally I would prefer naming them after the date they are designated. Ex. 9192012; if 2 are designated on the same date 9192012-A and 9192012-B. More sciencey.


Too sciencey...most folks need it kept as simple as possible..not everyone hangs out of a weather site..LOL
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Quoting TomballTXPride:

Your version of fun is different than mine, Bud.


Thank goodness for that, bud!!!
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Who could forget Irenes landfall in Humacao,PR ? I certainly couldn't although maybe I did for a few minutes. Thanks Vlad!
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Quoting Vlad959810:

Hugo, Hortense, Georges and Irene


Dont forget Jeanne in 2004 that was almost a hurricane when it crossed PR.
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Quoting jascott1967:


Yet we give them human names.

Personally I would prefer naming them after the date they are designated. Ex. 9192012; if 2 are designated on the same date 9192012-A and 9192012-B. More sciencey.


That "date" name would be tricky as much of the world uses the day-month-year order.
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Quoting jascott1967:
Not quoted
Please, the children!
Member Since: September 16, 2005 Posts: 0 Comments: 3167

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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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