Invest 98L spinning up; outlook for remainder of hurricane season

By: Dr. Jeff Masters , 19. syyskuuta 2011 klo 14:09 (GMT)

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A tropical wave midway between Africa and the Lesser Antilles (Invest 98L) continues to look well-organized on satellite imagery, with a modest amount of heavy thunderstorm activity and spin. An ASCAT pass from 8:08 pm EDT last night showed 98L was close to closing off a well-defined surface circulation. Wind shear as diagnosed by the SHIPS model is light, less than 10 knots, and is predicted to stay light to moderate through Friday. Ocean temperatures are 28 - 28.5°C, well above the threshold typically needed for a tropical storm to spin up. Water vapor satellite images show 98L is embedded in a moist environment, but there is dry air to the system's northwest. However, given the light wind shear, this dry air may not pose a hindrance to development at this time. An analysis of upper level winds from the University of Wisconsin CIMMS group shows a pattern favorable for development, with an outflow channel open to both the north and south available to ventilate the storm and allow 98L to efficiently lift plenty of moisture to high levels.


Figure 1. Morning satellite image of 98L.

The models are not very aggressive about developing 98L into a tropical depression, but most of them do show some weak development. NHC gave the disturbance a 60% chance of developing into a tropical depression by Wednesday in their 8 am Tropical Weather Outlook. Given the recent increase in spin on visible satellite images and favorable environment for development, I'd bump these odds up to 70%. 98L is currently moving little, but is expected to begin a westward motion at 10 mph today. This motion would take 98L into the Lesser Antilles Islands by Friday or Saturday. The northern Lesser Antilles would be most likely to see the core of the storm, as has been the case for all of this year's disturbances. However, a more southerly path across Barbados, as predicted by the GFS model, cannot be ruled out. Once 98L does reach the Lesser Antilles, all of the models indicate the storm will see a sharp increase in vertical wind shear due to strong upper-level winds out of the west. This shear should make it difficult for 98L to intensify as it moves though the islands.

Atlantic hurricane outlook for the rest of September
Ocean temperatures are starting to decline in the North Atlantic, though remain much above average in the Main Development Region (MDR) for hurricanes, from the coast of Africa to the coast of Central America, between 10°N and 20°N latitude. The latest departure of sea surface temperature (SST) from average plot (Figure 2) shows a large area of ocean temperatures near 1°C above average. The water temperatures were 0.8°C above average in this region during August, which is the 4th highest such reading on record. These warm waters will allow for an above-average chance of African tropical waves developing through early October. By early October, the African Monsoon typically begins to wane, spawning fewer tropical waves that tend to be weaker, and we should stop seeing development of newly-emerged tropical waves off the coast of Africa.


Figure 2. Departure of sea surface temperature (SST) from average for September 19, 2011. Ocean temperatures were about 1°C above average over much of the Main Development Region (MDR) for hurricanes, from the coast of Africa to the coast of Central America, between 10°N and 20°N latitude. In the Pacific off the coast of South America, we can see the tell-tale signature of a La Niña event, with cooler than average waters along the Equator. Also note the cooler than average waters between Bermuda and Puerto Rico, due to the passage of Hurricane Maria and Hurricane Katia. Image credit: NOAA/NESDIS.

Wind shear has been near average over the tropical Atlantic this hurricane season, and is currently at its climatological low point, which occurs in mid-September. The latest 2-week run of the GFS model shows wind shear will remain at the sort of typical low levels we usually see this time of year. With ocean temperatures at near-record warm levels, this combination would tend to favor formation of at least two tropical storms between now and the beginning of October. One inhibiting factor, though, may be the continued presence of dry, stable air over the tropical Atlantic. Hurricanes like to have an unstable atmosphere, with moist, warm air near the surface, and cold, dryer air aloft. This situation helps the updrafts in the storm grow stronger. This year, we've had unusually stable air (Figure 3.) This has really put the brakes on intensification of most of the tropical storms that have formed. The current ratio of 14 named storms but only 3 hurricanes is unprecedented in the historical record, going back to 1851. Usually, just over half of all Atlantic tropical storms intensify into hurricanes. One other factor to consider, the 30-60 day pattern of increased thunderstorm activity known as the Madden-Jullian Oscillation (MJO), looks like it will have little influence over the coming week. The MJO has been weak all month, and is predicted to stay weak for the remainder of this week.


Figure 3. Vertical instability, as measured by the difference in temperature near the surface to the bottom of the stratosphere. The atmosphere in the Caribbean (left) and tropical Atlantic between Africa and the Lesser Antilles Islands (right) has been much more stable than average this year (average is the thick black line). Image credit: NOAA/CIRA.

Forecast of the rest of hurricane season
We are past the half-way point of the Atlantic hurricane season, which typically peaks on September 10. On average, about 60% of the activity has occurred by this point in the season. Since we've already had 14 named storms and 3 hurricanes, at the current rate, we would expect to see another 8 or 9 named storms, with 1 or 2 of them reaching hurricane strength. It's pretty tough to maintain the sort of activity levels we've seen so far this year, so I am forecasting we'll see 7 more named storms during the remainder of this season, taking us all the way to "W" in the alphabet. With the unusually stable air over the Atlantic showing no signs of abating, I predict that we'll see just 2 of these storms reach hurricane strength. As far as steering currents go, the latest 2-week forecast from the GFS model doesn't show any significant changes to the jet stream pattern we've seen all summer. There will continue to be a parade of troughs of low pressure moving off the U.S. East Coast that will tend to curve any storms northwards and then northeastwards out to sea, once they penetrate north of the Lesser Antilles Islands. This pattern favors strikes on North Carolina and New England, and discourages strikes on Texas. I doubt Texas will see a tropical storm this year given this steering pattern, and considering that Texas' tropical cyclone season tends to peak in late August and early September. It is quite unusual for Texas to have a tropical storm or hurricane this late in the season, so they will probably have to look elsewhere for drought-busting rains.

Jeff Masters

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832. VAbeachhurricanes
20. syyskuuta 2011 klo 17:19 (GMT)
well i see everyone has officially left...
Member Since: 6.09.2007 Posts: 0 Comments: 5709
831. CaribBoy
20. syyskuuta 2011 klo 15:45 (GMT)
EVERYONE WAKE UPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
Member Since: 6.10.2007 Posts: 0 Comments: 5606
830. MTWX
20. syyskuuta 2011 klo 15:42 (GMT)
Wow either something is wrong, or noone is on the blog right now!
Member Since: 20.07.2009 Posts: 23 Comments: 1391
829. redwagon
20. syyskuuta 2011 klo 15:27 (GMT)
Quoting ncstorm:
Interesting to see if this trough off our coast could turn in to something..a lot of rain being predicted for eastern NC..





What might the blue/purple off TX/LA, be that we don't see? Be nice if a cut-off something span up, ran south and strengthened, then drifted back to S TX.
Member Since: 4.08.2007 Posts: 0 Comments: 2813
828. ncstorm
20. syyskuuta 2011 klo 14:31 (GMT)
Interesting to see if this trough off our coast could turn in to something..a lot of rain being predicted for eastern NC..

Member Since: 19.08.2006 Posts: 13 Comments: 13483
827. hydrus
20. syyskuuta 2011 klo 14:03 (GMT)
Member Since: 27.09.2007 Posts: 1 Comments: 19608
826. GeoffreyWPB
20. syyskuuta 2011 klo 13:54 (GMT)
Puerto Rico NWS Discussion

LOOKING AHEAD...A BROAD AREA OF LOW PRESSURE WILL CONTINUE TO
DEVELOP FARTHER TO THE EAST OF THE WINDWARD ISLANDS. SHOWERS AND
THUNDERSTORMS ARE GRADUALLY INCREASING...AND ENVIRONMENTAL
CONDITIONS APPEAR FAVORABLE FOR A TROPICAL DEPRESSION TO FORM DURING
THE NEXT COUPLE OF DAYS. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES SLOWLY
WESTWARD. HOWEVER...AT THIS TIME THE GFS AND THE ECMWF COMPUTER
MODELS MOVE THIS SYSTEM ACROSS THE LOCAL ISLANDS ONLY AS AN OPEN
WAVE LATE SUNDAY AND MONDAY. STAY TUNED.
Member Since: 10.09.2007 Posts: 0 Comments: 10589
825. AussieStorm
20. syyskuuta 2011 klo 13:53 (GMT)
G'day all.
Well fire season has started with a bang. as of today, there is 47 bush fires burning in NSW.
2 are burning the Blue mountains west of Sydney. there is also a bush fire burning in the SW suburbs of Sydney that closed the main highway to Canberra and Melbourne. Today's weather conditions were very ugly and ripe for fire ignition. Sustained wind were 50km/h(31mph) gusting up to 80-100km/h(50-62mph). A almost completed sports Stadium in Woolongong south of Sydney has sustained damage and is on the verge of collapse.









This is what everyone in NSW was dreading, Last year there was only a few bush fires due to the inclement weather, and flooding. This has caused the undergrowth to become a cinder pot waiting to explode.

I will post more info when it comes to hand.


How is Texas and Florida going with there bush fires?
Member Since: 30.09.2007 Posts: 9 Comments: 15750
824. GeoffreyWPB
20. syyskuuta 2011 klo 13:40 (GMT)
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
0930 AM EDT TUE 20 SEPTEMBER 2011
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 21/1100Z TO 22/1100Z SEPTEMBER 2011
TCPOD NUMBER.....11-112

I. ATLANTIC REQUIREMENTS
1. NEGATIVE RECONNAISANCE REQUIREMENTS.
2. SUCCEEDING DAY OUTLOOK: BEGIN 6-HRLY FIXES AT
23/1200Z ON A SYSTEM NEAR 13.5N 54.0W.
Member Since: 10.09.2007 Posts: 0 Comments: 10589
823. ScottGridley
20. syyskuuta 2011 klo 13:31 (GMT)
Long time listener, first time caller: surprised to see strong low-level circulation near the canadian maritimes this morning now that the deep convection is gone...must be deep extratropical or you guys missed one!
Member Since: 3.06.2007 Posts: 0 Comments: 10
821. hydrus
20. syyskuuta 2011 klo 13:26 (GMT)
Quoting MTWX:
99L is trying really hard to pull something off. Link
Tenacious little thing.....I think it wants a shot at da title...
Member Since: 27.09.2007 Posts: 1 Comments: 19608
819. aspectre
20. syyskuuta 2011 klo 13:18 (GMT)
deleted, meant to to temporarily store some coordinates then reflexively posted.
Member Since: 21.08.2007 Posts: 0 Comments: 4860
818. JLPR2
20. syyskuuta 2011 klo 13:18 (GMT)
Quoting MTWX:
99L is trying really hard to pull something off. Link


Seems like it wants some attention.
Member Since: 4.09.2007 Posts: 7 Comments: 8459
817. islander101010
20. syyskuuta 2011 klo 13:18 (GMT)
Quoting hurricane23:
In terms of the U.S with a huge trof progged by the globals this thing will get shunted to the NE sooner rather then later as many this season.

Could come close to some of the islands before its turned.
thats why watching the nw carib development is important
Member Since: 11.09.2010 Posts: 0 Comments: 4018
816. MTWX
20. syyskuuta 2011 klo 13:15 (GMT)
99L is trying really hard to pull something off. Link
Member Since: 20.07.2009 Posts: 23 Comments: 1391
815. hydrus
20. syyskuuta 2011 klo 13:15 (GMT)
Quoting coffeecrusader:
98L will be pulled North and NE out to sea like Maria and the previous storms. The GFDL has been WAY off this year with a very left bias. The only chance for a Florida storm this year will be in October when pressures lower in the Carib and the upward MJO returns. So far no hints of anything forming in this region from the long range GFS. Looks like a 10-14 day lull until the October action begins.
And the upward phase of the MJO should be in our region of the world during October, when there is a second round of increased activity... Link
Member Since: 27.09.2007 Posts: 1 Comments: 19608
814. hydrus
20. syyskuuta 2011 klo 13:03 (GMT)
Member Since: 27.09.2007 Posts: 1 Comments: 19608
813. weathermanwannabe
20. syyskuuta 2011 klo 13:00 (GMT)
Good Morning. Per CIMSS there are a few bands of moderately high sheer on the NE quadrant of the system at the moment so I am not too sure that we will have a TD by today unless it stays below it or the sheer wanes off a bit over the next 48 hours. Just my opinion.

Link
Member Since: 8.08.2006 Posts: 0 Comments: 8311
812. coffeecrusader
20. syyskuuta 2011 klo 12:59 (GMT)
98L will be pulled North and NE out to sea like Maria and the previous storms. The GFDL has been WAY off this year with a very left bias. The only chance for a Florida storm this year will be in October when pressures lower in the Carib and the upward MJO returns. So far no hints of anything forming in this region from the long range GFS. Looks like a 10-14 day lull until the October action begins.
Member Since: 21.08.2006 Posts: 0 Comments: 254
811. weaverwxman
20. syyskuuta 2011 klo 12:59 (GMT)
Been Watching 98l, I think it will become a min TS
sometime tomorrow. But its forward speed and dry air ahead will not allow for much intensification, therefore possibly keeping it on the more southerly track into carib. We will see what happens. JMO
Glad we have something to watch into the weekend.
Member Since: 17.11.2009 Posts: 0 Comments: 343
810. KEEPEROFTHEGATE (Mod)
20. syyskuuta 2011 klo 12:58 (GMT)
ALERT ATCF MIL 98X XXX 110920060000
2011092006
11.3 322.3
11.3 319.2
100
11.3 322.3
201000
1109201000
1
WTNT21 KNGU 201000
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/1. FORMATION OF A TROPICAL CYCLONE IS POSSIBLE WITHIN 100NM
EITHER SIDE OF A LINE FROM 11.3N 37.7W TO 11.3N 40.8W OVER THE
NEXT 24HOURS. AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF
A NUMBERED TROPICAL CYCLONE WARNING AT THIS TIME. WINDS ASSOCIATED
WITH THIS DISTURBANCE ARE ESTIMATED TO BE AROUND 25KTS.
SATELLITE IMAGERY AT 0815Z INDICATES THAT A CIRCULATION CENTER
IS LOCATED NEAR 11.3N 037.7W MOVING WESTWARD AT 5 TO 10 KTS.
2. A 1008MB LOW IS EMBEDDED ALONG THE MONSOON TROUGH
AXIS NEAR 11N37W, OR APPROXIMATELY 1300NM EAST OF WINWARD ISLANDS,
AND HAS BECOME BETTER DEFINED IN THE LAST 6 HOURS.
DVORAK SATELLITE ESTIMATE AS OF 20/0545Z IS CURRENTLY T1.5/1.5.
WIND SHEAR VALUES OF 10 TO 20 KTS ARE MARGINAL FOR SLOW DEVELOPMENT
OF THIS SYSTEM AS IT TRACKS WESTWARD. SEA SURFACE TEMPERATURES
OF 84 TO 88 DEGREES FAHRENHEIT EXIST IN THE REGION.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO A WARNING, CANCELLED OR
ALLOWED TO EXPIRE BY 211000Z.//9811091700 99N 369W 15
9811091706 99N 364W 15
9811091712 100N 358W 20
9811091718 104N 353W 20
9811091800 110N 350W 20
9811091806 117N 350W 25
9811091812 120N 357W 25
9811091818 119N 362W 25
9811091900 117N 367W 25
9811091906 117N 372W 25
9811091912 111N 372W 25
9811091918 108N 364W 25
9811092000 113N 372W 25
9811092006 113N 377W 25

Member Since: 15.07.2006 Posts: 165 Comments: 52406
808. stoormfury
20. syyskuuta 2011 klo 12:50 (GMT)
the multi layer steering takes 98L/td16 west or slightly north of west the next 4 days close to the central windward islands
Member Since: 22.08.2006 Posts: 0 Comments: 2552
807. hydrus
20. syyskuuta 2011 klo 12:45 (GMT)
Quoting Seflhurricane:
so if the current steering pattern holds through the season any system that forms over the NW Carribbean would move towards South Florida Like Wilma
Especially with the number of troughs we have been having..Florida gets whacked in October than any other state..I have been through a few myself.
Member Since: 27.09.2007 Posts: 1 Comments: 19608
806. MTWX
20. syyskuuta 2011 klo 12:45 (GMT)
99L's rotation looks really good on visible, but all of the convection is popping well to the east of the center.
Member Since: 20.07.2009 Posts: 23 Comments: 1391
804. 7544
20. syyskuuta 2011 klo 12:35 (GMT)
morning all looks like 98l will be a td or ts sometime today and ex99.looking good could that one surpise us

note now the gfdl has 98l as hurricane at 15n 72 west will it get just below dr then turn n or ne toward fla possibly a fay track with the trofs coming down . this one would . could be all about timimg and fla should keep one eye on this one .
Member Since: 6.05.2007 Posts: 0 Comments: 6618
803. SLU
20. syyskuuta 2011 klo 12:33 (GMT)
Quoting stoormfury:
SLU
my take on 98L earlier this morning was 40 mph ophelia


To me it still looks a little ragged to be called a tropical storm. It needs a burst of convection near the center 1st. But this is certainly at least a TD now.
Member Since: 13.07.2006 Posts: 12 Comments: 4734
802. SLU
20. syyskuuta 2011 klo 12:31 (GMT)
869

WHXX01 KWBC 201229

CHGHUR

TROPICAL CYCLONE GUIDANCE MESSAGE

NWS NATIONAL HURRICANE CENTER MIAMI FL

1229 UTC TUE SEP 20 2011



DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.

PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE

AND SUBTROPICAL CYCLONE INFORMATION.



ATLANTIC OBJECTIVE AIDS FOR



DISTURBANCE INVEST (AL982011) 20110920 1200 UTC



...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...

110920 1200 110921 0000 110921 1200 110922 0000



LAT LON LAT LON LAT LON LAT LON

BAMS 11.5N 37.5W 12.4N 40.5W 12.9N 44.2W 13.1N 48.4W

BAMD 11.5N 37.5W 12.1N 39.4W 12.8N 41.5W 13.6N 43.7W

BAMM 11.5N 37.5W 12.1N 39.6W 12.7N 42.2W 13.2N 44.9W

LBAR 11.5N 37.5W 12.1N 39.0W 13.0N 41.0W 14.2N 43.5W

SHIP 25KTS 29KTS 34KTS 39KTS

DSHP 25KTS 29KTS 34KTS 39KTS



...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...

110922 1200 110923 1200 110924 1200 110925 1200



LAT LON LAT LON LAT LON LAT LON

BAMS 12.7N 52.9W 10.8N 60.9W 9.7N 67.0W 10.4N 70.6W

BAMD 14.4N 45.9W 16.4N 49.6W 18.5N 52.8W 19.6N 54.8W

BAMM 13.6N 47.6W 14.8N 52.2W 16.9N 56.6W 18.7N 60.5W

LBAR 15.3N 46.2W 17.9N 51.7W 21.4N 56.2W 23.7N 58.3W

SHIP 42KTS 45KTS 47KTS 45KTS

DSHP 42KTS 45KTS 47KTS 45KTS



...INITIAL CONDITIONS...

LATCUR = 11.5N LONCUR = 37.5W DIRCUR = 280DEG SPDCUR = 4KT

LATM12 = 11.3N LONM12 = 36.7W DIRM12 = 316DEG SPDM12 = 4KT

LATM24 = 11.1N LONM24 = 37.2W

WNDCUR = 25KT RMAXWD = 50NM WNDM12 = 25KT

CENPRS = 1008MB OUTPRS = 1012MB OUTRAD = 150NM SDEPTH = M

RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM



$$

NNNN
Member Since: 13.07.2006 Posts: 12 Comments: 4734
801. stoormfury
20. syyskuuta 2011 klo 12:30 (GMT)
98L/ OPHELIA should increase in foreward speed sometime today
Member Since: 22.08.2006 Posts: 0 Comments: 2552
800. stormpetrol
20. syyskuuta 2011 klo 12:30 (GMT)
Member Since: 29.04.2007 Posts: 0 Comments: 7506
799. stoormfury
20. syyskuuta 2011 klo 12:25 (GMT)
SLU
my take on 98L earlier this morning was 40 mph ophelia
Member Since: 22.08.2006 Posts: 0 Comments: 2552
798. Seflhurricane
20. syyskuuta 2011 klo 12:17 (GMT)
so if the current steering pattern holds through the season any system that forms over the NW Carribbean would move towards South Florida Like Wilma
Member Since: 14.07.2009 Posts: 0 Comments: 2990
797. SLU
20. syyskuuta 2011 klo 12:17 (GMT)
TADAAAAAAAAAAAAA!!

20/1145 UTC 11.7N 36.7W T2.0/2.0 98L -- Atlantic
Member Since: 13.07.2006 Posts: 12 Comments: 4734
796. hydrus
20. syyskuuta 2011 klo 12:10 (GMT)
Member Since: 27.09.2007 Posts: 1 Comments: 19608
795. NASA101
20. syyskuuta 2011 klo 12:05 (GMT)
06Z GFDL has a hurricane at 15N - 72W....
Member Since: 16.08.2007 Posts: 0 Comments: 276
794. Tazmanian
20. syyskuuta 2011 klo 11:48 (GMT)
Quoting TropicalAnalystwx13:


you don't "have to".



so ture
Member Since: 21.05.2006 Posts: 5089 Comments: 114075
793. GeoffreyWPB
20. syyskuuta 2011 klo 11:48 (GMT)
Member Since: 10.09.2007 Posts: 0 Comments: 10589
792. Chicklit
20. syyskuuta 2011 klo 11:47 (GMT)
Member Since: 11.07.2006 Posts: 14 Comments: 11047
791. Chicklit
20. syyskuuta 2011 klo 11:46 (GMT)

Atlantic Tropical Weather Discussion
------------------------------------------------- -------------------------------


000
AXNT20 KNHC 201139
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT TUE SEP 20 2011

...BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC.

...SPECIAL FEATURES...

A 1008 MB LOW IS EMBEDDED ALONG THE MONSOON TROUGH AXIS NEAR 11N38W MOVING W AT 5-10 KT. TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT LOW-LEVEL MOISTURE IS MAXIMIZED FROM 07N-15N BETWEEN 31W-41W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 09N-13N BETWEEN 35W-42W. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM LATER TODAY OR ON WEDNESDAY. ...TROPICAL WAVES...

TROPICAL WAVE IS ANALYZED FROM 10N-18N ALONG 17W MOVING W AT 10-15 KT. VISIBLE METEOSAT-9 SATELLITE IMAGERY INDICATES A BROAD LOW TO MID-LEVEL CYCLONIC CIRCULATION HAS EMERGED OFF THE COAST OF W AFRICA. EXAMINING RECENT UPPER AIR TIME SECTION ANALYSES FROM BAMAKO MALI...THIS WAVE APPEARS TO HAVE PASSED AROUND 18/1200 UTC AND IS POISED TO FULLY PASS DAKAR SENEGAL...AT THE SURFACE AND ALOFT...THIS MORNING. DEEP CONVECTION REMAINS LIMITED WITH ISOLATED MODERATE CONVECTION FROM 12N-15N BETWEEN
17W-20W.

Member Since: 11.07.2006 Posts: 14 Comments: 11047
790. TropicalAnalystwx13
20. syyskuuta 2011 klo 11:45 (GMT)
They're being very stubborn with 98L:

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT TUE SEP 20 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND THUNDERSTORMS ASSOCIATED WITH A LARGE LOW PRESSURE
SYSTEM LOCATED ABOUT 1500 MILES EAST OF THE WINDWARD ISLANDS
CONTINUE TO SHOW SIGNS OF ORGANIZATION. ENVIRONMENTAL CONDITIONS
ARE EXPECTED TO REMAIN CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM
LATER TODAY OR ON WEDNESDAY. THIS SYSTEM HAS A HIGH CHANCE...70
PERCENT
...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS
AS IT MOVES WESTWARD AT 5 TO 10 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER PASCH
Member Since: 6.07.2010 Posts: 109 Comments: 30300
789. TropicalAnalystwx13
20. syyskuuta 2011 klo 11:44 (GMT)
Quoting Tazmanian:




yes it may hae come back but un less they re put 99L up you have too call it EX 99L


you don't "have to".
Member Since: 6.07.2010 Posts: 109 Comments: 30300
788. Tazmanian
20. syyskuuta 2011 klo 11:43 (GMT)
Quoting PensacolaDoug:



Not quite.




yes it has come back but un less they re put 99L up you have too call it EX 99L
Member Since: 21.05.2006 Posts: 5089 Comments: 114075
787. TropicalAnalystwx13
20. syyskuuta 2011 klo 11:43 (GMT)
Quoting Chicklit:

You're not the only one who thinks this way!




Only the GFS and GFDL initialized it right, so I'm discounting all the others...

Its not moving NW, its moving W
Member Since: 6.07.2010 Posts: 109 Comments: 30300
786. Chicklit
20. syyskuuta 2011 klo 11:42 (GMT)
Quoting hurricane23:
In terms of the U.S with a huge trof progged by the globals this thing will get shunted to the NE sooner rather then later as many this season.

Could come close to some of the islands before its turned.

You're not the only one who thinks this way!


Member Since: 11.07.2006 Posts: 14 Comments: 11047
785. PensacolaDoug
20. syyskuuta 2011 klo 11:39 (GMT)
Quoting Tazmanian:



99L is gone



Not quite.
Member Since: 25.07.2006 Posts: 0 Comments: 519
784. GeoffreyWPB
20. syyskuuta 2011 klo 11:39 (GMT)
TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT TUE SEP 20 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

CLOUDINESS AND THUNDERSTORMS ASSOCIATED WITH A LARGE LOW PRESSURE
SYSTEM LOCATED ABOUT 1500 MILES EAST OF THE WINDWARD ISLANDS
CONTINUE TO SHOW SIGNS OF ORGANIZATION. ENVIRONMENTAL CONDITIONS
ARE EXPECTED TO REMAIN CONDUCIVE FOR A TROPICAL DEPRESSION TO FORM
LATER TODAY OR ON WEDNESDAY. THIS SYSTEM HAS A HIGH CHANCE...70
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS
AS IT MOVES WESTWARD AT 5 TO 10 MPH.
Member Since: 10.09.2007 Posts: 0 Comments: 10589
783. TropicalAnalystwx13
20. syyskuuta 2011 klo 11:37 (GMT)
Good Morning All.

What happened to Post-99L? It has convection now, and looks decent! See:



All I will say about 98L is...

Tropical Depression Sixteen: COMING SOON

Member Since: 6.07.2010 Posts: 109 Comments: 30300
782. Tazmanian
20. syyskuuta 2011 klo 11:31 (GMT)
Quoting islander101010:
could be a race for the o storm between old 99 and 98



99L is gone
Member Since: 21.05.2006 Posts: 5089 Comments: 114075

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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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