Danny weakens further; 94L worth watching

By: Dr. Jeff Masters , 1:54 PM GMT on August 28, 2009

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Tropical Storm Danny continues to weaken, and may merely be a tropical depression. Data from the Hurricane Hunters early this morning showed top winds of just 40 mph at the surface, and satellite intensity estimates of Danny's strength are now rating the storm a tropical depression. Danny looks very disorganized on satellite imagery (Figure 1), with the low-level circulation center exposed to view. There is no heavy thunderstorm activity near Danny's center, and only a small area of heavy thunderstorms lying several hundred miles east of the center.


Figure 1. Morning satellite image of Danny, showing the exposed swirl of clouds where Danny's center is, well displaced from the heaviest thunderstorm activity to the east.

The forecast for Danny
With wind shear at 15 knots this morning, and forecast to increase to 20 knots tonight and 30 knots Saturday morning, is is unlikely Danny will be able to strengthen to more than a 50 mph tropical storm. Dry air from the upper-level low that has been keeping Danny disorganized continues to be a problem for the storm, as well. The GFDL and HWRF models continue to insist Danny will strengthen to a strong tropical storm or weak Category 1 hurricane, but this seems very unrealistic given Danny's current struggles. With Danny's heavy thunderstorms all on the east side of the storm, it is unlikely that New England will feel tropical storm force winds from Danny when it scoots past on Saturday. Large swells from Danny creating high surf along the beaches of New England will be the primary hazard from the storm.

Massachusetts hurricane history
Two tropical storms have affected Massachusetts in the past decade, though neither of these storms brought sustained winds of tropical storm force (39 mph) to the state. Tropical Storm Beryl of 2006 just missed Cape Cod as a weak tropical storm with 45 mph winds. Beryl brought wind gusts to tropical storm force to Nantucket Island, and a 1 foot storm surge. Tropical Storm Hermine hit southeast Massachusetts on August 31, 2004, as a minimum-strength tropical storm with 40 mph winds. No land stations in Massachusetts reported tropical storm force winds during Beryl. The last time Massachusetts measured tropical storm force winds was in 1991 during Hurricane Bob, which hit Rhode Island as a Category 2 hurricane. Provincetown, Massachusetts measured sustained winds of 98 mph, gusting to 115 mph, and Buzzard's Bay received a 15 foot storm surge.


Figure 2. Tropical wave 94L, a few hundred miles west of the Cape Verdes Islands.

Invest 94L
A well-organized tropical wave (94L) lies a few hundred miles west-southwest of the Cape Verdes Islands. This disturbance has shown little change this morning. This morning's QuikSCAT pass shows a complete circulation, elongated in the east-west direction, with top winds of 30 mph. Satellite imagery shows only a small amount of heavy thunderstorm activity near the circulation center, but considerable thunderstorm activity south of the center. Shear is low, about 10 knots, and is expected to remain low to moderate, 5 - 15 knots, over the next five days. The waters are warm enough to support development, 28°C, and are expected to remain in the 27 - 28°C range over the next five days. The dry Saharan Air Layer (SAL) lies about 200 miles to the north and west of 94L, and it appears from water vapor satellite imagery that a modest amount of dry air from the SAL is now being ingested into the storm, slowing development. Dry air will continue to slow development until 94L's heavy thunderstorm activity can moisten the atmosphere enough to shield the storm from the Saharan Air Layer. NHC is giving 94L a medium (30 - 50% chance) of developing into a tropical depression by Sunday. The GFDL and SHIPS models both predict 94L will be a Category 1 hurricane five days from now. However, the HWRF model does not develop 94L. Most of the models predict 94L will take a significant northward jog 3 - 5 days from now, in response to a strong trough of low pressure passing to the north (this is the same trough of low pressure that will be recurving Danny out to sea). It is then probable that 94L will be forced to the west again as the high pressure ridge steering the storm builds back in, and 94L will likely be a few hundred miles northeast of the Northern Lesser Antilles Islands seven days from now.

I'll have an update this afternoon.

Jeff Masters

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174. bwat
Quoting hamla:
if danny boy gets to 30.3 and 76.0 and stops for 12 hrs that east blob could make things interesteng
just a thought
It may make it there, who knows, but that ULL aint gonna let him sit for 12 hours by no means.
Member Since: August 18, 2009 Posts: 0 Comments: 353
Quoting Patrap:
The Se ULL has more "oomph" than Danny does and will Likely give more rain to many than Danny ever will.



And it borught and awesome light show down here in Mississippi Gulf Coast yesterday morning too. I would be much more concerned about 94L since Dr Masters says it will eventually start moving to the west after a jog to the north. Worth watching. By looking at the cuurent weather patterns I can say with some ceratinty that the Gulf Coast will be pretty much shielded this year, but the East Coast might not be as lucky. It feels like here in the Mississippi Gulf Coast like an early Fall I even saw Love Bugs flying around already.
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danny
Member Since: June 28, 2006 Posts: 25 Comments: 8360
171. hamla
if danny boy gets to 30.3 and 76.0 and stops for 12 hrs that east blob could make things interesteng
just a thought
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170. bwat
Quoting tropicfreak:


Which could mean rain for the OBX and for Eastern VA.
The only way I think we will see any significant rain in easter nc is if Danny can bring some of that convection to his east towards the north. That's possible, but not probable.
Member Since: August 18, 2009 Posts: 0 Comments: 353
Forget Danny, 94L is more interesting :D
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Quoting jeffs713:

The rain is having a hard time pentrating the CT/RI border. 8pm looks about right.


Dude, it's already raining in New Bedford and soon Buzzards Bay. We're going to get it way before 8pm.
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At this rate 94L is gonna make landfall in South America!!!
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Link

Who was that Troll who kept talking about tubes being the way to cool the ocean? Well, according to this link, Bill Gates stole your idea.
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.WATCHES/WARNINGS...
A TROPICAL STORM WATCH IS IN EFFECT FOR PORTIONS OF THE
MASSACHUSETTS COASTAL WATERS SOUTH OF MARTHAS VINEYARD AND NANTUCKET
AND EAST OF CAPE COD.

.SITUATION OVERVIEW...
TROPICAL STORM DANNY IS FORECAST TO TRACK CLOSE TO NANTUCKET
SATURDAY EVENING. BASED ON THIS TRACK...TROPICAL STORM FORCE WINDS
ARE POSSIBLE OVER THE WATERS SOUTH AND EAST OF NANTUCKET SATURDAY
AFTERNOON AND EVENING WITH SEAS BUILDING UP TO 15 FEET SATURDAY
NIGHT.

Danny's really going to have to get moving to make it there by tomorrow evening.
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Quoting jasoniscoolman10:
wow hurricane danny will be a cat 4 its this a joke...


I think they messed up.
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Quoting ncstorm:
DESPITE THE WESTWARD SHIFT IN THE TRACK...A TROPICAL STORM WARNING
WILL NOT BE ISSUED FOR THE COAST OF NORTH CAROLINA AT THIS
TIME...
DUE TO THE CURRENT AND EXPECTED LIMITED EXTENT OF TROPICAL
STORM FORCE WINDS ON THE WEST SIDE OF THE CIRCULATION. THE TROPICAL
STORM WATCH REMAINS IN EFFECT IN CASE THE WIND FIELD BECOMES BETTER
DEFINED ON THE WESTERN SIDE OF DANNY OR IF THE FORECAST CONTINUES
TO SHIFT WESTWARD. A TROPICAL STORM WATCH MAY ALSO BE NEEDED FOR
PORTIONS OF THE COAST OF NEW ENGLAND LATER TODAY.

Lets hope Danny turns because if not???


Not so much turning, but strength. No warning, but a watch. Latest:

AMZ150-152-154-156-291600-
/O.CON.KMHX.TR.A.0001.000000T0000Z-000000T0000Z/
S OF CURRITUCK BEACH LIGHT TO OREGON INLET NC OUT 20 NM-
S OF OREGON INLET TO CAPE HATTERAS NC OUT 20 NM-
S OF CAPE HATTERAS TO OCRACOKE INLET NC OUT 20 NM
INCLUDING THE MONITOR NATIONAL MARINE SANCTUARY-
S OF OCRACOKE INLET TO CAPE LOOKOUT NC OUT 20 NM-
1151 AM EDT FRI AUG 28 2009

...TROPICAL STORM WATCH REMAINS IN EFFECT...

...NEW INFORMATION...
THE INITIAL TRACK OF DANNY HAS SHIFTED SLIGHTLY TO THE WEST.
COASTAL INTERESTS SHOULD REMAIN ALERT TO THE PROGRESS OF DANNY.

...PROBABILITY OF TROPICAL STORM/HURRICANE CONDITIONS...
THERE IS LITTLE CHANCE FOR HURRICANE CONDITIONS AT THIS TIME.
THE CHANCE FOR TROPICAL STORM CONDITIONS AT THIS TIME IS AS HIGH
AS 39 PERCENT. THIS REPRESENTS A GENERAL UPWARD TREND SINCE THE
LAST FORECAST.

...WINDS...
AS TROPICAL STORM DANNY MOVES CLOSER WINDS WILL INCREASE. THE
LATEST FORECAST IS FOR WINDS TO APPROACH TROPICAL STORM FORCE.

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Quoting jasoniscoolman10:
the new path is back to the west a little bite.


Which could mean rain for the OBX and for Eastern VA.
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Quoting klaatuborada:
Talking about getting things wrong....

Our forecast is for the Cape of Cod:

This Afternoon
Mostly cloudy. Near steady temperature in the lower 70s. East winds 5 to 10 mph

Tonight
Cloudy. A chance of showers in the evening...then showers with thunderstorms likely after midnight. Lows in the mid 60s. Southeast winds 15 to 20 mph. Gusts up to 30 mph. Chance of rain 90.

Hourly forecast shows rain at 8:00 pm

and here's our radar as if 11:41 am:



I'm thinking rain before 8:00pm

The rain is having a hard time pentrating the CT/RI border. 8pm looks about right.
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Quoting NOVArules:


Yeah that ull is making it rain like crazy up here in virginia

EDIT: nvm it's a cold front.


Really, Here in richmond we haven't seen any rain yet. Some rather heavy rain showers are heading this way.
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Quoting Patrap:
The Se ULL has more "oomph" than Danny does and will Likely give more rain to many than Danny ever will.



Yeah that ull is making it rain like crazy up here in virginia

EDIT: nvm it's a cold front.
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The Se ULL has more "oomph" than Danny does and will Likely give more rain to many than Danny ever will.

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Quoting jasoniscoolman10:
wow hurricane danny will be a cat 4 its this a joke...


Lol yeah, Danny is fail right now
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DESPITE THE WESTWARD SHIFT IN THE TRACK...A TROPICAL STORM WARNING
WILL NOT BE ISSUED FOR THE COAST OF NORTH CAROLINA AT THIS
TIME...
DUE TO THE CURRENT AND EXPECTED LIMITED EXTENT OF TROPICAL
STORM FORCE WINDS ON THE WEST SIDE OF THE CIRCULATION. THE TROPICAL
STORM WATCH REMAINS IN EFFECT IN CASE THE WIND FIELD BECOMES BETTER
DEFINED ON THE WESTERN SIDE OF DANNY OR IF THE FORECAST CONTINUES
TO SHIFT WESTWARD. A TROPICAL STORM WATCH MAY ALSO BE NEEDED FOR
PORTIONS OF THE COAST OF NEW ENGLAND LATER TODAY.

Lets hope Danny turns because if not???
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wow hurricane danny will be a cat 4 its this a joke...
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Quoting klaatuborada:
Talking about getting things wrong....

Our forecast is for the Cape of Cod:

This Afternoon
Mostly cloudy. Near steady temperature in the lower 70s. East winds 5 to 10 mph

Tonight
Cloudy. A chance of showers in the evening...then showers with thunderstorms likely after midnight. Lows in the mid 60s. Southeast winds 15 to 20 mph. Gusts up to 30 mph. Chance of rain 90.

Hourly forecast shows rain at 8:00 pm

and here's our radar as if 11:41 am:



I'm thinking rain before 8:00pm
splitting hairs looks like to me
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here we go..
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Talking about getting things wrong....

Our forecast is for the Cape of Cod:

This Afternoon
Mostly cloudy. Near steady temperature in the lower 70s. East winds 5 to 10 mph

Tonight
Cloudy. A chance of showers in the evening...then showers with thunderstorms likely after midnight. Lows in the mid 60s. Southeast winds 15 to 20 mph. Gusts up to 30 mph. Chance of rain 90.

Hourly forecast shows rain at 8:00 pm

and here's our radar as if 11:41 am:



I'm thinking rain before 8:00pm
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IF 94l gets to the area danny has been churning up for the last few days... has danny been around long enough to bring cooler temps to the surface?
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Looks like Danny decided to wink at us this morning.

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A lot depends on the strenght of 94L whether it gets picked up by the trough.
Member Since: September 6, 2007 Posts: 887 Comments: 15965
Don't you guys think that 94L is too far to the south to get picked up by the trough of low pressure that it currently guiding Danny? What do you guys think?
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Quoting Chiggy007:
Nott gettng this: Most of the 8am (EST)GFS ensemble points 94L to the carribean but the GFS 8am run is ponting well awa to the North - shouldn't it be an average of all the ensembles...

or am I missing something here...!!


No, the main GFS runs is not an average of the ensembles. the main GFS run is run with the best estimate data, and I believe is run with better resolution. the ensembles are run with data udjusted for possible uncertainty, and i think it's a simpler version of the model.
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folks here in southeast georgia are about to get some good rain......nat'l. weather service activated spotters for out area this morning.......bring it on!!
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143. P451
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141. P451
WEATHER SUMMARY FOR SOUTHEASTERN NY...NORTHEASTERN NJ AND SOUTHERN CT
NATIONAL WEATHER SERVICE NEW YORK NY
500 AM EDT FRI AUG 28 2009

TROPICAL SYSTEM DANNY WILL TRACK OVER 100 MILES SOUTHEAST OF MONTAUK
POINT SATURDAY EVENING. LOCALLY HEAVY RAINFALL IS POSSIBLE AHEAD OF
THE STORM. IN ADDITION...GUSTY WINDS WITH THE STORM COULD CAUSE HIGH
SURF...MINOR BEACH EROSION...AND POSSIBLY COASTAL
FLOODING...ESPECIALLY OVER COASTAL AREAS OF EASTERN LONG ISLAND AND
POSSIBLY SOUTHEAST CONNECTICUT. ALL INTERESTS IN THE AREA SHOULD
MONITOR THE PROGRESS OF DANNY...AS ANY WESTWARD DEVIATION IN THE
TRACK COULD RESULT IN SIGNIFICANT STORM IMPACTS OCCURRING FARTHER
WEST.
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Quoting StormW:
TROPICAL WEATHER SYNOPSIS /DANNY/ /94L/ AUG. 28, 2009 ISSUED 8:00 A.M. EDT

Thanks for the update Storm. I can always count on you to speak in a language that makes sense. All these other weather experts speak in terms that 75% of us, who are are learning, don't understand.
I will apologize now if someone is offended anyone if by including them in the 75%.
Just by reading this blog every day, most of the bloggers make me laugh with their comments and opinions; especially last night with "carrabbean"
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139. P451
1445Z (Its presently 1515Z)

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138. 786
so now we are faced with a recurve of a weak system...go figure
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Looks like 94L is heading into lower shear, 29 degree SSTs, and virtually no SAL.

And see post #101 for wind barbs at 8 a.m. EST.
It's got dry air ahead of it.
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Update on Tropical Storm Krovanh in Western Pacific

23.7N 148.2E
Winds:50MPH
Moving N at 13MPH
Pressure:998MB

Interests in Southeastern Japan should monitor the progress of Krovanh. By 72 hours, Krovanh could make landfall as a 75 mph typhoon about 50 miles SW of Tokyo. Big change in track since 5AM warning.
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135. P451
Quoting fmbill:


But if he doesn't get "pulled", he will definitely get "run over".

That's a pretty decent system to the west heading toward him.


Danny will eventually have no choice but to get booted northward and when it happens he will accelerate quite rapidly.

He has no where to go. That surge from Florida is going to punt him northward when they meet up.
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134. eddye
i think se fl can get 94l
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133. P451
Quoting winter123:


So? Danny was always like that yet it was named.


Danny had a closed LLC near it's convection when it was born. This system has nothing but a broad area of low pressure quite a bit east of the convection. It's a different scenario IMO.

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132. P451
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Quoting P451:
A lot of players for the East Coast. Mid-Atlantic through the North East is in for it this weekend.




Those graphics look like a "landcane" is whirling around toward Louisiana - more stuff on land than at sea.
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Can shear be pushing it west?

ShearMap
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Quoting Stoopid1:
Not buying the forecast track at all. Danny will likely continue further westward before recurving, he is way too shallow to be pulled that much.


But if he doesn't get "pulled", he will definitely get "run over".

That's a pretty decent system to the west heading toward him.
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Hmm there is a decent possibility according to a local met that 94L will not only recurve but never even reach hurricane strength (it does reach storm strength he said) he said the Shear is too great and the high is too weak.
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look at fast 94L is moving at..its saying 23 mph...its moving west to.
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Not buying the forecast track at all. Danny will likely continue further westward before recurving, he is way too shallow to be pulled that much.
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Quoting Chicklit:
Hi Charleston. Both images are the same, from 13:15 UTC.
It's now 14:55 UTC. TimeClock
also 10:55 a.m. EST.
That Quickscat would've been from 8 a.m. this morning.
Good morning : )
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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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