Ophelia remains weak; TD 17 forms; dangerous Nesat headed for the Philippines

By: Dr. Jeff Masters , 4:54 PM GMT on September 24, 2011

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There's not much change to Tropical Storm Ophelia today, which continues to battle dry air and high wind shear. Satellite imagery shows that Ophelia has little heavy thunderstorm activity near its low level circulation center, which is mostly exposed to view. Most of the storm's heavy thunderstorms are to the east of the center, with just a few puffs of thunderstorms occasionally popping up near the center. An analysis from the University of Wisconsin CIMMS group shows a high 20 - 25 knots of wind shear due to strong upper-level southwesterly winds. Water vapor satellite images show Ophelia is at the eastern edge of large area of very dry air.


Figure 1. Afternoon satellite image of Ophelia showing the low-level center exposed to view, with all the storm's heavy thunderstorms in a band several hundred miles to the east and south. This is not a healthy-looking tropical storm.

Forecast for Ophelia
The latest SHIPS model forecast predicts that Ophelia will experience high wind shear of 20 - 40 knots over the next five days, and will move into a region with slightly drier air. This combination of shear and dry air may be enough to dissipate Ophelia, as predicted by several of the models. However, Ophelia has maintained itself better than the models have predicted, so the storm will probably survive until at least Sunday. Even it Ophelia does dissipate, it will have the chance to regenerate by Tuesday or Wednesday, when it may encounter a region of lower wind shear. At this time, it appears that Ophelia will only be a threat to Bermuda.

TD 17 forms
Tropical Depression 17 formed in the far eastern Atlantic off the coast of Africa last night, and is likely to intensify into Tropical Storm Philippe later today. TD 17 has some impressive low-level spiral bands and upper-level outflow, and is very close to tropical storm strength. The predicted west-northwest to northwest track of TD 17 will put it in a position where historically, very few storms have ever gone on to hit land.


Figure 2. MODIS satellite image of Hurricane Hilary at 4:05 pm EDT September 23, 2011. At the time, Hilary was a Category 4 storm with 145 mph winds. Image credit: NASA.

Powerful Hurricane Hilary remains at Category 4 strength
In the Eastern Pacific, Hurricane Hilary remains an impressive Category 4 hurricane with 140 mph winds. Hilary is headed west, away from Mexico, and the storm is small enough that its outer bands are not causing flooding problems for Mexico. A trough of low pressure expected to move over the Western U.S. by the middle of the week may be strong enough to turn Hilary to the north, eventually bringing Hilary to Mexico's Baja Peninsula. The timing of this event is highly uncertain, though. Hilary is small enough that it is unlikely to bring significant drought relief to Arizona, New Mexico, and Texas if the storm's remnants move north into those states. Hilary is the fourth Category 4 hurricane in the Eastern Pacific this year, and the second strongest, behind Hurricane Dora, which had 155 mph winds.

Invest 91L set to soak North Carolina
A moderate amount of heavy thunderstorm activity has developed over the Northwestern Bahamas in association with the tail end of an old stalled front. This disturbance, Invest 91L, is under a low 5 - 10 knots of wind shear, but water vapor loops show a considerable amount of dry air to the east and west of the disturbance that will likely interfere with development. In their 8 am Tropical Weather Outlook, NHC gave 91L a 20% chance of developing into a tropical depression by Monday. The disturbance has only a short window to develop, as it is headed northwards and is expected to make landfall in North Carolina by Sunday afternoon. The 8 am EDT SHIPS model forecast predicts 91L will hit 35 knots of wind shear by Sunday morning, when the storm will be approaching the coast of North Carolina. Heavy rains from 91L may cause localized flooding in Morehead City, NC and surrounding regions. A moist flow of tropical air over the region has already brought rainfall amounts of 1 - 3 inches to much of Eastern North Carolina today.

Dangerous Tropical Storm Nesat headed for the Philippines
What may be the season's most dangerous storm in the Western Pacific, Tropical Storm Nesat, has formed about 700 miles east of the Philippine Islands. Nesat is under a moderate 10 knots of wind shear, is embedded in a very moist environment, has very warm sea surface temperatures of 30°C under it, and a very favorable upper-level outflow pattern above it. Nesat has plenty of time to intensify into a major typhoon before its expected landfall on Luzon Island in the Philippines on Tuesday morning.

I'll have an update before 2 pm Sunday afternoon.

Jeff Masters

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EWRC

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Hilary is finaly going to EWRC. Lets see what the finished product looks like tmrw. Night All
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691 TropicalAnalystwx13 "lol, I'm bored, so..."

...it's time for Texcasting

292.8(WNW) is the initial heading from TS.Ophelia's 2nd most recent ATCF position to:
TS.Ophelia's most recent ATCF position;
RumCay,Bahamas;
PortAransas (across the bay from CorpusChristi).

Copy&paste 17.7n57.0w-18.1n58.0w, rcy, 17.7n57.0w-23.709n74.803w, 17.7n57.0w-ktfp into the GreatCircleMapper for more info
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759. JLPR2
Yep, mid level...




Almost no convergence in the area.


Looks like a funeral...
Member Since: September 4, 2007 Posts: 7 Comments: 8459
Quoting KEEPEROFTHEGATE:
looked at the sunspot map and thank God 1302 is not facing us directly.. it looked like 1301 is though.. hope it behaves itself!
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Quoting KoritheMan:
Just finished a blog update, if anyone wants to read.
Thanks Kori...So you think that Hilary (her remenants)will most likely recurve before getting to SoCal? and possible sending a good amount of energy into the AZ-TX.. (TX would be nice)
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Quoting redwagon:

Hilary is a tad off her forecast track.


a tad for sure...;).....it's a lully night...at least Keeper is here with some sun visuals...
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Funeral .... or wedding?


Wedding, and Philippe will be widowed pretty soon...
*Ophelia Gasps*
Oh no! She's going down!
*Philippe laughs*
lol
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Quoting JNCali:
they got a good shake out of it too.. They need a break for sure!


+1000

I think their break will not come until next year. They have had their share of storms, as well. No rest, for the weary. You have to admire their stamina.
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Quoting Some1Has2BtheRookie:


Careful. Japan suffered a "fish quake". Tsunamis can be more devastating than shaking buildings.
they got a good shake out of it too.. They need a break for sure!
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Quoting JNCali:
Agree.. hope its a 'fish' quake!


Careful. Japan suffered a "fish quake". Tsunamis can be more devastating than shaking buildings.
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Quoting KEEPEROFTHEGATE:
a large quake will follow too maybe by monday before 2
Agree.. hope its a 'fish' quake!
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748. JLPR2


Thinking O is going to reform her LLC under convection. As of now, all we probably have is a nice Mid-level circulation.
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Quoting JNCali:
More solar activity??
a large quake will follow too maybe by monday before 2
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Quoting EYEStoSEA:

Hilary is a tad off her forecast track.
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744. JLPR2
In comparison, look at Philippe.
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Quoting JLPR2:




gracias
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Quoting KEEPEROFTHEGATE:
More solar activity??
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keep the fish storms comin'!
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738. JLPR2
Quoting CybrTeddy:


I wouldn't call Ophelia 'RIP' yet, even if advisories are discontinued, it is pretty likely Ophelia will re-generate north of Puerto Rico and become a moderate TS again.. at least in my opinion. Similar to Colin last year.


Member Since: September 4, 2007 Posts: 7 Comments: 8459
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Good Night. Blog is slow, storms still spinning, even the NHC is bored lol.
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CV Season appears to be over I hope.
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So once again we have a system (Orphelia) which if stays weak can move westwatrd and possibly cause islands trouble or worse.. Or if she strengthens will most likely ride the ridge recurving into oblivion...
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000
WTNT42 KNHC 250255
TCDAT2

TROPICAL STORM PHILIPPE DISCUSSION NUMBER 4
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
1100 PM AST SAT SEP 24 2011

A 2344 UTC ASCAT PASS OVER PHILIPPE INDICATES THE LOW-LEVEL CENTER
IS LOCATED VERY NEAR A RECENT BURST OF DEEP CONVECTION...BUT THAT
THE MAXIMUM WINDS ARE PROBABLY BARELY 35 KT. SINCE THE CONVECTION
HAS BEEN ON A GENERAL UPWARD TREND OVER THE PAST COUPLE OF
HOURS...THE INITIAL INTENSITY IS HELD AT 35 KT.

PHILIPPE IS LOCATED ON THE SOUTHERN PERIPHERY OF A WEAK MID-LEVEL
RIDGE...AND THAT RIDGE IS EXPECTED TO SHIFT EASTWARD AND STRENGTHEN
NEAR THE AFRICAN COAST IN THE COMING DAYS AS A DEEP TROUGH DIGS
OVER THE CENTRAL ATLANTIC. THEREFORE...THE MOTION OF THE
CYCLONE...WHICH IS CURRENTLY 295/10 KT...IS FORECAST TO TURN
NORTHWESTWARD AND SLOW DOWN AS PHILIPPE MOVES BETWEEN THESE TWO
SYNOPTIC FEATURES. THERE IS VERY GOOD AGREEMENT AMONG THE MODELS
UNTIL ABOUT 72 HOURS...AFTER WHICH TIME THE GFS AND ECMWF SHOW A
SLOWER AND WESTWARD-LEANING MOTION WHILE THE BULK OF THE OTHER
MODELS INDICATE A TURN TOWARD THE NORTH AND NORTH-NORTHEAST. A
SLOWER MOTION IS FAVORED SINCE THERE IS A LOT OF UNCERTAINTY...AND
THE OFFICIAL FORECAST ENDS UP CLOSE TO THE GFS BY DAY 5.

THE FORECAST TRACK OF PHILIPPE NEVER REALLY TAKES THE CYCLONE OVER
SIGNIFICANTLY WARMER WATERS...AND THE UNDERLYING OCEAN SHOULD
DEFINITELY BE COOLER AFTER ABOUT 48 HOURS. IN ADDITION...PHILIPPE
SHOULD BE MOVING OUT OF AN ENVIRONMENT OF LIGHT UPPER-LEVEL WINDS
INTO AN AREA OF STRONGER SOUTHWESTERLY SHEAR IN ABOUT 3 DAYS.
THEREFORE...STRENGTHENING IS EXPECTED MAINLY DURING THE NEXT 48
HOURS WITH SOME WEAKENING POSSIBLE BY DAYS 4 AND 5. THE OFFICIAL
FORECAST LIES GENERALLY CLOSE TO THE INTENSITY CONSENSUS AND SHOWS
PHILIPPE BECOMING A HURRICANE IN THE 48-72 HOUR TIME FRAME.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 11.6N 28.8W 35 KT 40 MPH
12H 25/1200Z 12.1N 30.5W 40 KT 45 MPH
24H 26/0000Z 13.1N 32.5W 50 KT 60 MPH
36H 26/1200Z 14.1N 34.1W 55 KT 65 MPH
48H 27/0000Z 15.4N 35.3W 65 KT 75 MPH
72H 28/0000Z 18.0N 37.0W 65 KT 75 MPH
96H 29/0000Z 21.0N 38.0W 60 KT 70 MPH
120H 30/0000Z 24.0N 38.0W 60 KT 70 MPH

$$
FORECASTER BERG
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...PHILIPPE NO THREAT TO LAND...
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ESTIMATED MINIMUM CENTRAL PRESSURE 1006 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
Member Since: July 6, 2010 Posts: 108 Comments: 30251
Quoting Some1Has2BtheRookie:


Funeral .... or wedding?

Lol
Quoting CybrTeddy:


I wouldn't call Ophelia 'RIP' yet, even if advisories are discontinued, it is pretty likely Ophelia will re-generate north of Puerto Rico and become a moderate TS again.. at least in my opinion. Similar to Colin last year.

But for the moment, she's barely hanging on to life.
Member Since: July 7, 2010 Posts: 0 Comments: 5521
Quoting CybrTeddy:
IMO Ophelia is no longer a tropical cyclone, and just a sharply inverted tropical wave. Need a recon in or an ASCAT to confirm, but I expect advisories to be discontinued soon. That being said, I said the same thing about Maria and it became a hurricane a few days later.


AGREE!
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Quoting TropicalAnalystwx13:
TROPICAL STORM OPHELIA DISCUSSION NUMBER 17
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162011
1100 PM AST SAT SEP 24 2011

IT IS UNCLEAR WHETHER OR NOT OPHELIA STILL HAS A WELL-DEFINED
CENTER...BUT IN THE INTEREST OF CONTINUITY ADVISORIES ARE STILL
BEING ISSUED.
WITHOUT ANY NEW DATA TO CONTRADICT EARLIER
ESTIMATES...THE INTENSITY IS BEING HELD AT 40 KT...AND THE INITIAL
MOTION WILL BE MAINTAINED AT 295/10 KT.

THE TRACK AND INTENSITY FORECASTS ARE MORE LINKED TONIGHT THAN
USUAL. OPHELIA WILL BE MOVING ALONG THE SOUTHERN EDGE OF
A LOW- TO MID-LEVEL AREA OF HIGH PRESSURE OVER THE NEXT FEW
DAYS...AND THE EXACT TRACK WILL DEPEND ON WHAT KIND OF INTENSITY
OPHELIA CAN MAINTAIN. THE GFS AND ECMWF...USUALLY THE MOST
RELIABLE GLOBAL MODELS...SHOW OPHELIA CONTINUING TO BE BATTERED BY
STRONG SOUTHWESTERLY OR WESTERLY SHEAR AND THEREFORE SHOW A WEAKER
VORTEX MOVING FARTHER WEST. ON THE OTHER HAND...MANY OF THE OTHER
MODELS INDICATE THAT OPHELIA WILL STRENGTHEN AND CONSEQUENTLY TURN
NORTHWARD STEERED BY DEEPER FLOW. BASED ON THE OVERALL SYNOPTIC
ENVIRONMENT AND THE MORE LIKELY SCENARIO THAT THE VERTICAL SHEAR
WILL NOT DECREASE SIGNIFICANTLY IN THE COMING DAYS...THE OFFICIAL
FORECAST KEEPS OPHELIA AS A LOW-END TROPICAL STORM AND LEANS IN THE
DIRECTION OF THE GFS AND ECMWF...WHICH IS ALSO JUST TO THE WEST OF
THE TRACK MODEL CONSENSUS.

THERE IS A POSSIBILITY THAT OPHELIA COULD DEGENERATE INTO A TROUGH
OF LOW PRESURE AT ANY TIME IF IT IS DETERMINED THAT IT NO LONGER
HAS A WELL-DEFINED CENTER. SHOULD THAT HAPPEN...NHC WOULD NO
LONGER ISSUE ADVISORIES UNLESS IT REGENERATES INTO A TROPICAL
CYCLONE.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 18.3N 58.4W 40 KT 45 MPH
12H 25/1200Z 18.9N 59.8W 40 KT 45 MPH
24H 26/0000Z 19.8N 61.3W 35 KT 40 MPH
36H 26/1200Z 20.6N 62.6W 35 KT 40 MPH
48H 27/0000Z 21.3N 63.6W 35 KT 40 MPH
72H 28/0000Z 23.0N 65.0W 40 KT 45 MPH
96H 29/0000Z 24.5N 65.5W 45 KT 50 MPH
120H 30/0000Z 26.5N 66.0W 45 KT 50 MPH

$$
FORECASTER BERG


HUMMM!
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Quoting WeatherNerdPR:

We are gathered here today...


Funeral .... or wedding?
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Quoting WeatherNerdPR:

We are gathered here today...


I wouldn't call Ophelia 'RIP' yet, even if advisories are discontinued, it is pretty likely Ophelia will re-generate north of Puerto Rico and become a moderate TS again.. at least in my opinion. Similar to Colin last year.
Member Since: July 8, 2005 Posts: 259 Comments: 23012
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*Awaiting the NHC advisory on TS Philippe*
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hmmm what about PHILIPPE come on nhc dont be that lazy
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Quoting CybrTeddy:
IMO Ophelia is no longer a tropical cyclone, and just a sharply inverted tropical wave. Need a recon in or an ASCAT to confirm, but I expect advisories to be discontinued soon. That being said, I said the same thing about Maria and it became a hurricane a few days later.

We are gathered here today...
Member Since: July 7, 2010 Posts: 0 Comments: 5521
so OPHELIA could open up soon if it has not done so yet
Member Since: May 21, 2006 Posts: 5089 Comments: 114051
IMO Ophelia is no longer a tropical cyclone, and just a sharply inverted tropical wave. Need a recon in or an ASCAT to confirm, but I expect advisories to be discontinued soon. That being said, I said the same thing about Maria and it became a hurricane a few days later.
Member Since: July 8, 2005 Posts: 259 Comments: 23012
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NWS NATIONAL HURRICANE CENTER MIAMI FL AL162011
1100 PM AST SAT SEP 24 2011

...OPHELIA STRUGGLING TO SURVIVE AS A TROPICAL CYCLONE...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.3N 58.4W
ABOUT 310 MI...495 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES



-------------

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/H...WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 48
HOURS. HOWEVER...OPHELIA COULD DEGENERATE INTO A TROUGH OF LOW
PRESSURE AT ANY TIME IF IT NO LONGER HAS A WELL-DEFINED CENTER.
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Quoting JLPR2:
Hillary's eye is becoming too small.

How will she be able to see where she is going? I think she might start meandering.
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Quoting TropicalAnalystwx13:


lol at the first sentence.


Didn't even have to look at the forecaster who posted it without guessing who it was, Avila has a great sense of humor.
Member Since: July 8, 2005 Posts: 259 Comments: 23012
Quoting CybrTeddy:


.. I'll be here all week..

which comes as a source of annoyance to a great many people too.


You are safe, Cyber. I think the trolls finally got a date.
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TROPICAL STORM OPHELIA DISCUSSION NUMBER 17
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162011
1100 PM AST SAT SEP 24 2011

IT IS UNCLEAR WHETHER OR NOT OPHELIA STILL HAS A WELL-DEFINED
CENTER...BUT IN THE INTEREST OF CONTINUITY ADVISORIES ARE STILL
BEING ISSUED.
WITHOUT ANY NEW DATA TO CONTRADICT EARLIER
ESTIMATES...THE INTENSITY IS BEING HELD AT 40 KT...AND THE INITIAL
MOTION WILL BE MAINTAINED AT 295/10 KT.

THE TRACK AND INTENSITY FORECASTS ARE MORE LINKED TONIGHT THAN
USUAL. OPHELIA WILL BE MOVING ALONG THE SOUTHERN EDGE OF
A LOW- TO MID-LEVEL AREA OF HIGH PRESSURE OVER THE NEXT FEW
DAYS...AND THE EXACT TRACK WILL DEPEND ON WHAT KIND OF INTENSITY
OPHELIA CAN MAINTAIN. THE GFS AND ECMWF...USUALLY THE MOST
RELIABLE GLOBAL MODELS...SHOW OPHELIA CONTINUING TO BE BATTERED BY
STRONG SOUTHWESTERLY OR WESTERLY SHEAR AND THEREFORE SHOW A WEAKER
VORTEX MOVING FARTHER WEST. ON THE OTHER HAND...MANY OF THE OTHER
MODELS INDICATE THAT OPHELIA WILL STRENGTHEN AND CONSEQUENTLY TURN
NORTHWARD STEERED BY DEEPER FLOW. BASED ON THE OVERALL SYNOPTIC
ENVIRONMENT AND THE MORE LIKELY SCENARIO THAT THE VERTICAL SHEAR
WILL NOT DECREASE SIGNIFICANTLY IN THE COMING DAYS...THE OFFICIAL
FORECAST KEEPS OPHELIA AS A LOW-END TROPICAL STORM AND LEANS IN THE
DIRECTION OF THE GFS AND ECMWF...WHICH IS ALSO JUST TO THE WEST OF
THE TRACK MODEL CONSENSUS.

THERE IS A POSSIBILITY THAT OPHELIA COULD DEGENERATE INTO A TROUGH
OF LOW PRESURE AT ANY TIME IF IT IS DETERMINED THAT IT NO LONGER
HAS A WELL-DEFINED CENTER. SHOULD THAT HAPPEN...NHC WOULD NO
LONGER ISSUE ADVISORIES UNLESS IT REGENERATES INTO A TROPICAL
CYCLONE.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 18.3N 58.4W 40 KT 45 MPH
12H 25/1200Z 18.9N 59.8W 40 KT 45 MPH
24H 26/0000Z 19.8N 61.3W 35 KT 40 MPH
36H 26/1200Z 20.6N 62.6W 35 KT 40 MPH
48H 27/0000Z 21.3N 63.6W 35 KT 40 MPH
72H 28/0000Z 23.0N 65.0W 40 KT 45 MPH
96H 29/0000Z 24.5N 65.5W 45 KT 50 MPH
120H 30/0000Z 26.5N 66.0W 45 KT 50 MPH

$$
FORECASTER BERG
Member Since: July 6, 2010 Posts: 108 Comments: 30251

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About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.