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 Stoopid1:
90L a.k.a. the remnants of Isaac. Impressive how long a big storm like Isaac can retain it's identity. Seems like it has a fair chance of redevelopment (would still be Isaac if it did) but it only has a limited window so it's doubtful.

Those facts are completely off.

As the NHC stated yesterday, this is a "PIECE" of Isaac and would mean that it would receive a new name, Nadine, and has the possibility of becoming a Weak Tropical Cyclone as it stalls out over the next couple of days.
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1136. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Noaa Buoy just off the Florida Panhandle pressure is dropping

Station 42012
NDBC
Location: 30.065N 87.555W
Date: Wed, 05 Sep 2012 11:50:00 UTC
Significant Wave Height: 2.3 ft
Dominant Wave Period: 5 sec
Mean Wave Direction: SW (230°)
Atmospheric Pressure: 29.84 in and falling
Air Temperature: 78.8 F
Dew Point: 75.0 F

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1134. WxLogic
Quoting 7544:


now those look interesting over fl then loop around the bahmamas then what back to fl AGAIN LOL


LOL I was about to comment about that too... that would be real something if it were to happen... assuming it develops.
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1133. LargoFl
Quoting Hurricane1956:
We are leaving for Captiva Island this weekend on vacations I hope this system will not spoiled our vacations,but indeed it looks very impressive in the satellite presentation,I believe this system could surprise many people,in my opinion a strong tropical strong and depending how long it seat in the Gulf of Mexico will not be surprise to see a Cat#1.
Again we hope it will not spoiled our mini-vacation this weekend.
have a great time on your vacation!
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Quoting indianrivguy:


Mornin' Geoffrey!. I was looking at the radar loops like this earlier this morning and came away fascinated that the storms are forming the instant the airmass pushed over water.. they aren't really popping over land.


Good morning! True, and they are still forming at a quick pace.
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90L a.k.a. the remnants of Isaac. Impressive how long a big storm like Isaac can retain it's identity. Seems like it has a fair chance of redevelopment (would still be Isaac if it did) but it only has a limited window so it's doubtful.
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1130. Grothar


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Quoting GeoffreyWPB:

Looks like Isaac's little sister(Nadine) wants to finish the job in Florida, as Isaac was first forecasted to go for the RNC, but Isaac had other plans... ;)
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1128. LargoFl
Quoting Grothar:
..look at that path..just about the same path as debby
Member Since: August 6, 2011 Posts: 4 Comments: 40993
1127. 7544
Quoting GeoffreyWPB:


now those look interesting over fl then loop around the bahmamas then what back to fl AGAIN LOL
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=doesnt.hit.conus
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1125. Grothar
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1124. LargoFl
bad storms midwest also today, lots of warnings out.......
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
756 AM CDT WED SEP 5 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
EAST CENTRAL GREENE COUNTY IN SOUTHWEST ILLINOIS...
MACOUPIN COUNTY IN SOUTHWEST ILLINOIS...
SOUTHWESTERN MONTGOMERY COUNTY IN SOUTH CENTRAL ILLINOIS...

* UNTIL 900 AM CDT

* AT 752 AM CDT...A LINE OF SEVERE THUNDERSTORMS WAS LOCATED ALONG A
LINE EXTENDING FROM THAYER TO 5 MILES WEST OF PALMYRA TO WHITE
HALL...AND MOVING SOUTHEAST AT 45 MPH.

HAZARD...60 MPH WIND GUSTS.

SOURCE...RADAR INDICATED.

IMPACT...MINOR TREE DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER
BROKEN.

* LOCATIONS IMPACTED INCLUDE...
VIRDEN...CARLINVILLE...LITCHFIELD...GILLESPIE...HI LLSBORO...
STAUNTON...GREENFIELD...GIRARD...FARMERSVILLE...RA YMOND...BENLD...
WILSONVILLE...MOUNT OLIVE...TAYLOR SPRINGS...HETTICK...NILWOOD...
STANDARD CITY...CHESTERFIELD...WAGGONER AND ATWATER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

LARGE HAIL...DAMAGING WINDS AND CONTINUOUS CLOUD TO GROUND LIGHTNING
IS OCCURRING WITH THESE STORMS. MOVE INDOORS IMMEDIATELY. LIGHTNING
KILLS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO
BE STRUCK BY LIGHTNING.
Member Since: August 6, 2011 Posts: 4 Comments: 40993
I think it's still too raw for the people of the Gulf coast to have Isaac just reform and pop up on their doorstep again, people would probably lose it.
On the other-hand the NHC didn't seem to mind Ivan as it looped around, and reformed it in the Gulf.
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1122. guygee
Quoting LargoFl:
surfers will be out in those dangerous rip currents along the east coast for sure huh
Rip currents are not the danger, fear is the danger. The human body is buoyant in the ocean's salt water, if you remain calm and breathe steadily you will naturally float. This applies to bubble-free water, when there are bubbles you lose buoyancy. The common advice is so true, let the current take you out beyond the surf zone, then relax and swim parallel to the beach...or just float if you cannot swim, the return current will take you back to shore.

Fear and panic causes drowning, not rip currents.
Member Since: September 16, 2005 Posts: 0 Comments: 3174
Quoting LargoFl:
boy that sure looks impressive for only 20% huh
We are leaving for Captiva Island this weekend on vacations I hope this system will not spoiled our vacations,but indeed it looks very impressive in the satellite presentation,I believe this system could surprise many people,in my opinion a strong tropical strong and depending how long it seat in the Gulf of Mexico will not be surprise to see a Cat#1.
Again we hope it will not spoiled our mini-vacation this weekend.
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Quoting Eng1n3rd:
Possibly off-topic, but I've been lurking for awhile and I've seen this phrase tossed around, "fish storm"; what does it mean? Thanks!
It's just a highly-overused (in this forum, anyway) slang term denoting a non-landfalling cyclone.
Member Since: November 8, 2009 Posts: 4 Comments: 13611
Quoting TropicalAnalystwx13:

Most tropical cyclones develop from waves that cross the Atlantic and enter the East Pacific. There's really no way for them to develop if they're developing in our basin.

Lol, I have no idea.

The only activity the EPAC has been capable of getting is a couple of monsoonal lows that escaped the Atlantic. other than that. Nothin.

We currently lead the EPAC
13-10

Back in July it was:
4-7

Major shift, wasn't it?
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1117. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Headed to Pizza for Pearlington, MS Ironically, also headed back in to what is left of Isaac.
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Quoting Eng1n3rd:
Possibly off-topic, but I've been lurking for awhile and I've seen this phrase tossed around, "fish storm"; what does it mean? Thanks!

A storm that does not affect a land mass - only bothers the fish.
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I'm off to school. I mean, *Clears throat, Prison.

High school isn't much of a prison to me. xD


Anyway.
Leslie and Michael both have a almost completely finished eyewall, which means they just need to adjust their structures and pop that eye out.

Leslie shall be a Hurricane tonight.
Michael shall be a Hurricane tomorrow.
90L will become Nadine this weekend.
and Oscar will form out of the Tropical Wave in central-west Africa in 5 days.
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Quoting GeoffreyWPB:


Mornin' Geoffrey!. I was looking at the radar loops like this earlier this morning and came away fascinated that the storms are forming the instant the airmass pushed over water.. they aren't really popping over land.
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Quoting Eng1n3rd:
Possibly off-topic, but I've been lurking for awhile and I've seen this phrase tossed around, "fish storm"; what does it mean? Thanks!


A "fish storm" is when a storm forms and doesn't hit any land masses as a TC.

A lot of people will rudely or incorrectly call something a "Fish Storm" even though it hits islands, which is not fair to the people living there.
Member Since: January 25, 2012 Posts: 33 Comments: 1520
Possibly off-topic, but I've been lurking for awhile and I've seen this phrase tossed around, "fish storm"; what does it mean? Thanks!
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1109. LargoFl
boy that sure looks impressive for only 20% huh
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Rob Masson @robmassonfox8
a strange new storm system in the gulf.

The Associated Press @AP
BREAKING: Area around US embassy in Brussels sealed off as bomb squad assesses suspicious vehicle.
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1107. guygee
Quoting LargoFl:
surfers will be out in those dangerous rip currents along the east coast for sure huh
Will get an increasing north longshore current with big rollers...surfer's dream around here.
Member Since: September 16, 2005 Posts: 0 Comments: 3174
Something about I storms - Ivan pulled a loop and went back through the Gulf in '04.
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1105. LargoFl
Quoting WxLogic:


That is one (of many questions)... won't be surprised if it misses the TROF and meanders in the E GOM.
yeah the longer it sits in the gulf, the more time to build
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Quoting weatherh98:
Judge (mom) is sending me to prison(school) as well gotta role


Recommend learn whatever you can in school.

If you're not already taking "trig/advanced math" (whatever they call it in your school,) and at least pre-calculus, do so, and if they offer a full Calculus course take it as well.


Unless you're exceptional at arts or music, you should take as little of that as you're allowed to and focus on any and all math and science courses available in your school. Take as little P.E. or ROTC as possible too.


I screwed up all of my "electives" in high school, and was horribly prepared for college, even though my primary curriculum was supposedly "college prep". Took 4 ROTC and 2 ARt classes, and that should have been 2 P.e.(w/ health) and 1 fine arts, and spend the other 3 on more math and science.

I regret nearly everything I did in high school regarding curriculum, because it absolutely ruined my college experience, and whatever "fun" I might have had in High School at the time was most certainly not worth it in the long term.


Personally, I think we need another month or two added to the school year so that less "review" is done and more in-depth teaching.

Other nations' kids have roughly four EXTRA U.S. school year equivalents of education by the time they graduate High School, due to the cummulative benefits of extra months in the school year. This is one of the two big reasons they out-perform American students in Math and Science.

The other reason is that many of the high schools require a scholarship and accept only the best students from junior high, and so the lowest scoring students aren't counted at all...


Anyway, this is both personal advice and social commentary. Take it for what you will. I'll pm this to you as well, since it's unlikely you're around to read it now.

Oh yeah, spend a lot of time in the Library reading math and science books and journals there as well...
Member Since: January 25, 2012 Posts: 33 Comments: 1520
Quoting allancalderini:
looks like Nadine and possible Oscar for the weekend and start of next week.btw why is the Eastern pacific dead right now?

Most tropical cyclones develop from waves that cross the Atlantic and enter the East Pacific. There's really no way for them to develop if they're developing in our basin.

Lol, I have no idea.
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1102. LargoFl
surfers will be out in those dangerous rip currents along the east coast for sure huh
Member Since: August 6, 2011 Posts: 4 Comments: 40993
1101. WxLogic
Quoting LargoFl:
...........big question is..will leslie pull future nadine to her or along her path?


That is one (of many questions)... won't be surprised if it misses the TROF and meanders in the E GOM.
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1100. guygee
Quoting islander101010:
lakes.are.full..e.cen.florida
I still feel like we have been parched this summer in Satellite Beach. Rain has been mostly from synoptic forcing or tropical-related...seabreeze rain machine broken-down...too many consecutive days with no rain and full sunshine. Subsoil is dry, topsoil is hydrophobic, plants are stunted.
Member Since: September 16, 2005 Posts: 0 Comments: 3174
looks like Nadine and possible Oscar for the weekend and start of next week.btw why is the Eastern pacific dead right now?
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1098. LargoFl
...........big question is..will leslie pull future nadine to her or along her path?
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Nadine .. Honey is that you ???
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1096. guygee
Big ULL over the Bahamas that was formerly forecast to roll over the FL peninsula 2-3 days ago now looks to be starting towards the N-NE. Ex-Isaac MLC to revisit N.O. before dropping into the GOM moving ESE?
Member Since: September 16, 2005 Posts: 0 Comments: 3174
1095. LargoFl
FLOOD WATCH...CORRECTED
NATIONAL WEATHER SERVICE MOBILE AL
633 AM CDT WED SEP 5 2012

...A FLASH FLOOD WATCH IS IN EFFECT FOR PORTIONS OF SOUTHWEST ALABAMA
AND THE WESTERN FLORIDA PANHANDLE THROUGH THIS EVENING...

.A LOW PRESSURE SYSTEM THAT IS ASSOCIATED WITH THE REMNANTS OF
TROPICAL DEPRESSION ISAAC WILL CONTINUE TO MOVE SOUTHWARD TODAY AND
TONIGHT...SHIFTING SOUTH OF THE IMMEDIATE COAST LATER THIS MORNING.
HEAVY RAIN ASSOCIATED WITH THIS PATTERN WILL OCCUR MOSTLY SOUTH OF A
LINE FROM ANDALUSIA TO MOBILE IN ALABAMA EARLY TODAY SHIFTING SOUTH
TO THE IMMEDIATE COASTAL AREAS BY THIS EVENING. ADDITIONAL RAINFALL
AMOUNTS UP TO 2 TO 4 INCHES WILL BE POSSIBLE IN THE WATCH AREA THROUGH
MIDDAY...TAPERING OFF FROM NORTH TO SOUTH THROUGH EARLY THIS
EVENING.
Member Since: August 6, 2011 Posts: 4 Comments: 40993
Quoting lobdelse81:

Anything after Leslie that we need to worry about in terms of a possible threat down the road?


90L as being discussed, and it is too early to tell where that Cape Verde wave may go.
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lakes.are.full..e.cen.florida
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Quoting CybrTeddy:
Looks like we might be in store for another CV storm in a few days. 00z UKMET.

06z GFS.

00z CMC.


If you are unsure of the next names on the list are Nadine, Oscar, Patty, Rafael, Sandy, Tony, Valerie, and William.

Assuming that Leslie does become a major hurricane, Michael becomes a hurricane, 90L develops into Nadine, and we get Oscar all by 5 days, I will be impressed. That's a lot of assumption, but certainly possible.

Anything after Leslie that we need to worry about in terms of a possible threat down the road?
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Scene type for Leslie has changed from irregular CDO to UNIFORM CDO CLOUD REGION w/ MW EYE (Microwave eye)
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1090. LargoFl
wow look at that..................
Member Since: August 6, 2011 Posts: 4 Comments: 40993
1089. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 40993
1088. WxLogic
As of 12Z... Convergence/Divergence appear to be on the increase on 90L:



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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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