T Storm Helene Advisories=Last Advisory Written by NHC

[LaBreeze]

Looks like a fish similar to Gordon. We are certainly hitting it lucky with all of these fish - didn't know fishing was going to be this good.

[bayoubebe]

Looks like a fish similar to Gordon. We are certainly hitting it lucky with all of these fish - didn't know fishing was going to be this good.

Why is it?

What is making these latter systems turn right and steer away from the US?

[Meso]

000
WTNT43 KNHC 130833
TCDAT3
TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 AM EDT WED SEP 13 2006

SATELLITE IMAGERY SHOWS THAT THE DEPRESSION IS POORLY
ORGANIZED...WITH DEEP CONVECTION REMAINING DISPLACED WEST OF THE
CENTER. GIVEN THE ABSENCE OF CONVECTION NEAR THE CIRCULATION
CENTER...THE INITIAL INTENSITY IS HELD AT 30 KT IN ACCORDANCE WITH
LATEST DVORAK ESTIMATES.

THE CONVECTIVE PATTERN APPEARS TO BE DUE TO A STRONG LOWER TO
MID-LEVEL JET IMPINGING UPON THE DEPRESSION. UPPER-AIR SOUNDINGS
DURING THE PAST 24 HOURS FROM DAKAR AND SAL CAPE VERDE...ALONG WITH
SPECIAL SOUNDINGS FROM THE AMMA PROJECT...SHOW THAT A STRONG 700 MB
JET ACCOMPANIED THE SYSTEM AFTER IT EMERGED FROM AFRICA.
ADDITIONALLY...THE METEOSAT-8 SPLIT WINDOW CHANNEL DIFFERENCING
PRODUCT PRODUCED BY UW-CIMSS SHOWS A LARGE SAHARAN AIR LAYER NORTH
OF THE SYSTEM. THERMAL WIND BALANCE WOULD ARGUE FOR A MID-LEVEL JET
ALONG THE SOUTHERN EDGE OF THAT VERY WARM AND STABLE AIRMASS. UNTIL
THE DEPRESSION CAN ESCAPE THIS SEEMINGLY UNFAVORABLE ENVIRONMENT...
SIGNIFICANT STRENGTHENING APPEARS LESS LIKELY. ADDITIONALLY...SUCH
A BROAD CIRCULATION PRECLUDES SIGNIFICANT STRENGTHENING IN THE
SHORT-TERM. THE 850-200 MB WIND SHEAR CALCULATION USED IN THE SHIPS
MODEL CANNOT RESOLVE THE APPARENT MID-LEVEL SHEAR IN THIS CASE.
ACCORDINGLY...THE INTENSITY FORECAST IS BELOW THE SHIPS
GUIDANCE...WHICH FORECASTS A HURRICANE WITHIN 48 HOURS...AND IS
CLOSER TO THE MORE CONSERVATIVE GFDL. HOWEVER...TOWARD THE END OF
THE FORECAST...THE GLOBAL MODELS INDICATE AN IMPROVED ENVIRONMENT
FOR STRENGTHENING. THE NEW FORECAST IS A LITTLE LOWER THAN THE
PREVIOUS ADVISORY...BUT STILL ANTICIPATES A HURRICANE LATE IN THE
PERIOD.

THE BROAD CIRCULATION OF THE SYSTEM MAKES IT DIFFICULT TO PRECISELY
IDENTIFY A CENTER. TRACKING THE MEAN CENTER OF THE LARGE GYRE YIELDS
AN INITIAL MOTION ESTIMATE OF 275/14. GLOBAL MODELS ARE IN GOOD
AGREEMENT THAT THE CYCLONE WILL BE STEERED AROUND THE SOUTHERN
PERIPHERY OF THE SUBTROPICAL RIDGE DURING THE NEXT 2-3 DAYS.
THEREAFTER...THE CYCLONE WILL ENCOUNTER A BREAK IN THE RIDGE
RESULTING IN A GRADUAL NORTHWARD TURN AND DECELERATION. THE
OFFICIAL FORECAST IS SHIFTED NORTH OF THE PREVIOUS ADVISORY AND
LIES JUST SOUTH OF THE DYNAMICAL MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 13/0900Z 11.9N 26.7W 30 KT
12HR VT 13/1800Z 12.2N 29.0W 30 KT
24HR VT 14/0600Z 12.8N 32.3W 35 KT
36HR VT 14/1800Z 13.7N 35.2W 40 KT
48HR VT 15/0600Z 14.7N 37.9W 45 KT
72HR VT 16/0600Z 17.5N 42.5W 55 KT
96HR VT 17/0600Z 19.5N 45.0W 65 KT
120HR VT 18/0600Z 21.5N 47.5W 80 KT

$$
FORECASTER RHOME/KNABB

[Brent]

TROPICAL DEPRESSION EIGHT FORECAST/ADVISORY NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1500 UTC WED SEP 13 2006

TROPICAL DEPRESSION CENTER LOCATED NEAR 12.0N 28.5W AT 13/1500Z
POSITION ACCURATE WITHIN 60 NM

PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 15 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 12.0N 28.5W AT 13/1500Z
AT 13/1200Z CENTER WAS LOCATED NEAR 11.9N 27.6W

FORECAST VALID 14/0000Z 12.2N 30.7W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 14/1200Z 12.8N 34.0W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 75NE 75SE 0SW 75NW.

FORECAST VALID 15/0000Z 13.8N 37.0W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 90NE 90SE 45SW 90NW.

FORECAST VALID 15/1200Z 15.1N 39.6W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 45NE 0SE 0SW 0NW.
34 KT... 90NE 90SE 60SW 90NW.

FORECAST VALID 16/1200Z 18.0N 43.5W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 45NE 45SE 30SW 45NW.
34 KT...100NE 100SE 75SW 100NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 17/1200Z 20.0N 46.5W
MAX WIND 70 KT...GUSTS 85 KT.

OUTLOOK VALID 18/1200Z 22.0N 49.5W
MAX WIND 80 KT...GUSTS 100 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 12.0N 28.5W

NEXT ADVISORY AT 13/2100Z

$$
FORECASTER BEVEN

[Brent]

BULLETIN
TROPICAL DEPRESSION EIGHT ADVISORY NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 AM EDT WED SEP 13 2006

...TROPICAL DEPRESSION MOVING WESTWARD WITH LITTLE CHANGE IN
ORGANIZATION...

AT 1100 AM EDT...1500Z...THE BROAD CENTER OF TROPICAL DEPRESSION
EIGHT WAS LOCATED NEAR LATITUDE 12.0 NORTH...LONGITUDE 28.5 WEST OR
ABOUT 335 MILES...540 KM...SOUTHWEST OF THE SOUTHERNMOST CAPE VERDE
ISLANDS.

THE DEPRESSION IS MOVING TOWARD THE WEST NEAR 17 MPH...27 KM/HR.
THIS GENERAL MOTION SHOULD CONTINUE FOR THE NEXT 24 HOURS WITH A
GRADUAL INCREASE IN FORWARD SPEED.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. SLOW STRENGTHENING IS EXPECTED...AND THE DEPRESSION COULD
BECOME A TROPICAL STORM DURING THE NEXT 24 HOURS.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.

REPEATING THE 1100 AM EDT POSITION...12.0 N...28.5 W. MOVEMENT
TOWARD...WEST NEAR 17 MPH. MAXIMUM SUSTAINED WINDS...35 MPH.
MINIMUM CENTRAL PRESSURE...1007 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM EDT.

$$
FORECASTER BEVEN

[Brent]

TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 AM EDT WED SEP 13 2006

MORNING VISIBLE IMAGERY INDICATES THAT TROPICAL DEPRESSION EIGHT
REMAINS POORLY ORGANIZED...WITH THE CIRCULATION ELONGATED
WEST-SOUTHWEST TO EAST-NORTHEAST AND SEVERAL VORTICITY MAXIMA
ROTATING AROUND THE MEAN CENTER. SCATTERED CONVECTIVE CLUSTERS ARE
PRESENT IN THE WESTERN SEMICIRCLE. SATELLITE INTENSITY ESTIMATES
ARE 30 KT FROM ALL AGENCIES...AND THAT REMAINS THE INITIAL
INTENSITY.

THE INITIAL MOTION IS 270/15. THE DEPRESSION IS SOUTH OF A
DEEP-LAYER RIDGE OVER THE EASTERN ATLANTIC...WHICH SHOULD KEEP THE
SYSTEM MOVING GENERALLY WESTWARD FOR 24 HR OR SO. AFTER THAT...THE
LARGE-SCALE MODELS FORECAST THE CYCLONE TO GRADUALLY TURN
WEST-NORTHWESTWARD AND THEN NORTHWESTWARD TOWARD A WEAKNESS IN THE
RIDGE NORTHEAST OF THE LESSER ANTILLES. ONE EXCEPTION TO THIS IS
THE CANADIAN MODEL...WHICH IS A LEFT OUTLIER BRINGING THE CYCLONE
TO JUST NORTHEAST OF THE LEEWARD ISLANDS BY 120 HR. THE NEW
FORECAST TRACK FOLLOWS THE MAJORITY OF THE GUIDANCE IN CALLING FOR
A NORTHWESTWARD MOTION BY 120 HR. THE NEW FORECAST TRACK IS A
LITTLE TO THE LEFT OF THE MODEL CONSENSUS DUE TO A PAST TENDENCY OF
THE LARGE-SCALE MODELS TO MOVE TROPICAL CYCLONES TOO FAR NORTH IN
THIS SYNOPTIC PATTERN.

THE CURRENT BROAD AND DISORGANIZED STRUCTURE SUGGESTS THAT
SHORT-TERM INTENSIFICATION SHOULD BE SLOW. THUS...THE INTENSITY
FORECAST TAKES 24 HR TO BRING THE DEPRESSION TO TROPICAL STORM
STRENGTH. AFTER THAT...THE SYSTEM SHOULD STRENGTHEN AT A FASTER
RATE IN A LIGHT VERTICAL SHEAR ENVIRONMENT...AND IT IS FORECAST TO
BECOME A HURRICANE IN 72-96 HR. THERE ARE TWO COMPLICATING FACTORS
IN THE INTENSITY FORECAST. THE FIRST IS DRY AIR PRESENT NORTH AND
WEST OF THE CYCLONE. HOW MUCH OF THIS AIR WILL BE ENTRAINED INTO
THE SYSTEM IS UNCLEAR AT THIS TIME. THE SECOND IS AN UPPER-LEVEL
TROUGH FORECAST BY THE LARGE-SCALE MODELS TO THE NORTH OR NORTHEAST
OF THE LESSER ANTILLES BY 120 HR. WHILE THE MODELS AGREE THE
TROUGH WILL EXIST...THEY DO NOT AGREE ON THE LOCATION OR ON THE
POSSIBLE IMPACT TO THE CYCLONE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 13/1500Z 12.0N 28.5W 30 KT
12HR VT 14/0000Z 12.2N 30.7W 30 KT
24HR VT 14/1200Z 12.8N 34.0W 35 KT
36HR VT 15/0000Z 13.8N 37.0W 40 KT
48HR VT 15/1200Z 15.1N 39.6W 50 KT
72HR VT 16/1200Z 18.0N 43.5W 60 KT
96HR VT 17/1200Z 20.0N 46.5W 70 KT
120HR VT 18/1200Z 22.0N 49.5W 80 KT

$$
FORECASTER BEVEN

[Evil Jeremy]

ZCZC MIATCDAT3 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 PM AST WED SEP 13 2006

SATELLITE IMAGERY THIS AFTERNOON INDICATES THAT TROPICAL DEPRESSION
EIGHT IS SLOWLY BECOMING BETTER ORGANIZED. A CONVECTIVE BAND HAS
FORMED IN THE NORTHWESTERN QUADRANT...ALTHOUGH THE BAND IS MORE
THAN 100 N MI FROM THE CENTER IN MOST AREAS. THE OVERALL
CIRCULATION IS MORE CIRCULAR AND BETTER DEFINED THAN 6 HR AGO.
SATELLITE INTENSITY ESTIMATES ARE 35 KT FROM TAFB...AND 30 KT FROM
SAB AND AFWA. THE INITIAL INTENSITY REMAINS 30 KT. IT SHOULD BE
NOTED THAT THE INITIAL POSITION IS SOUTH OF THE SATELLITE FIXES...
AND THE CENTER MAY BE TRYING TO RE-FORM FARTHER NORTH CLOSER TO THE
CONVECTION.

THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 275/16...WITH A POSSIBLE
FASTER MOTION OVER THE PAST FEW HOURS. THE DEPRESSION REMAINS
SOUTH OF A DEEP-LAYER RIDGE OVER THE EASTERN ATLANTIC...WHICH
SHOULD KEEP THE SYSTEM MOVING QUICKLY WESTWARD FOR 24 HR OR SO.
AFTER THAT...THE LARGE-SCALE MODELS FORECAST THE CYCLONE TO
GRADUALLY TURN WEST-NORTHWESTWARD AND THEN NORTHWESTWARD TOWARD A
WEAKNESS IN THE RIDGE NORTHEAST OF THE LESSER ANTILLES. THE UKMET
AND THE NOGAPS FORECAST MORE RIDGING NORTH OF THE DEPRESSION THAN
THEIR PREVIOUS RUNS...AND THEY TURN THE CYCLONE TO SOMEWHAT TO THE
LEFT AFTER 96 HR. THIS IS REFLECTED IN THE NEW FORECAST TRACK.
THE CANADIAN REMAINS A LEFT OUTLIER....ALTHOUGH IT HAS SHIFTED TO
THE RIGHT OF ITS PREVIOUS TRACK. THE GFS...GFDL...AND ECMWF ARE
SIMILAR TO THEIR PREVIOUS RUNS...WITH THE GFDL FASTER THAN THE
OTHER MODELS AFTER 72 HR. THE NEW FORECAST TRACK IS FASTER THAN
THE PREVIOUS TRACK DURING THE FIRST 24 HR...THEN IS SLOWER THAN THE
PREVIOUS TRACK AFTER 72 HR. IT LIES NEAR THE SOUTH EDGE OF THE
MAIN CLUSTER OF GUIDANCE.

THE BROAD STRUCTURE SUGGESTS THAT SHORT-TERM INTENSIFICATION SHOULD
BE SLOW. THIS IS REFLECTED IN THE FIRST 24 HR OF THE INTENSITY
FORECAST. THE SYSTEM SHOULD THEN STRENGTHEN AT A FASTER RATE IN A
LIGHT VERTICAL SHEAR ENVIRONMENT...AND IT IS FORECAST TO BECOME A
HURRICANE IN ABOUT 72 HR. THE INTENSITY FORECAST IS IN BEST
AGREEMENT WITH THE GFDL. THERE REMAIN TWO COMPLICATING FACTORS IN
THE INTENSITY FORECAST. THE FIRST IS DRY AIR PRESENT NORTH AND
WEST OF THE CYCLONE. HOW MUCH OF THIS AIR WILL BE ENTRAINED INTO
THE SYSTEM IS UNCLEAR. THE SECOND IS AN UPPER-LEVEL TROUGH
FORECAST BY THE LARGE-SCALE MODELS TO THE NORTH OR NORTHEAST OF THE
LESSER ANTILLES BY 96-120 HR. WHILE THE MODELS AGREE THE TROUGH
WILL EXIST...THEY DO NOT AGREE ON THE LOCATION OR ON THE POSSIBLE
IMPACT TO THE CYCLONE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 13/2100Z 12.7N 30.7W 30 KT
12HR VT 14/0600Z 12.9N 33.3W 35 KT
24HR VT 14/1800Z 13.6N 36.4W 40 KT
36HR VT 15/0600Z 14.7N 39.0W 50 KT
48HR VT 15/1800Z 16.1N 41.1W 60 KT
72HR VT 16/1800Z 18.5N 44.0W 70 KT
96HR VT 17/1800Z 20.5N 46.5W 80 KT
120HR VT 18/1800Z 22.0N 49.5W 85 KT

$$
FORECASTER BEVEN

NNNN

[Brent]

BULLETIN
TROPICAL DEPRESSION EIGHT ADVISORY NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 PM AST WED SEP 13 2006

...TROPICAL DEPRESSION EIGHT SLOWLY BECOMING BETTER ORGANIZED...

AT 500 PM AST...2100Z...THE CENTER OF TROPICAL DEPRESSION EIGHT WAS
LOCATED NEAR LATITUDE 12.7 NORTH...LONGITUDE 30.7 WEST OR ABOUT 445
MILES...720 KM...WEST-SOUTHWEST OF THE SOUTHERNMOST CAPE VERDE
ISLANDS.

THE DEPRESSION IS MOVING TOWARD THE WEST NEAR 18 MPH...29 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT
24 HOURS WITH SOME INCREASE IN FORWARD SPEED.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS...
AND THE DEPRESSION COULD BECOME A TROPICAL STORM TONIGHT OR
THURSDAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.

REPEATING THE 500 PM AST POSITION...12.7 N...30.7 W. MOVEMENT
TOWARD...WEST NEAR 18 MPH. MAXIMUM SUSTAINED WINDS...35 MPH.
MINIMUM CENTRAL PRESSURE...1007 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 PM AST.

$$
FORECASTER BEVEN

TROPICAL DEPRESSION EIGHT FORECAST/ADVISORY NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
2100 UTC WED SEP 13 2006

TROPICAL DEPRESSION CENTER LOCATED NEAR 12.7N 30.7W AT 13/2100Z
POSITION ACCURATE WITHIN 60 NM

PRESENT MOVEMENT TOWARD THE WEST OR 275 DEGREES AT 16 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 12.7N 30.7W AT 13/2100Z
AT 13/1800Z CENTER WAS LOCATED NEAR 12.6N 29.9W

FORECAST VALID 14/0600Z 12.9N 33.3W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 75NE 75SE 0SW 75NW.

FORECAST VALID 14/1800Z 13.6N 36.4W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 90NE 90SE 45SW 90NW.

FORECAST VALID 15/0600Z 14.7N 39.0W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 45NE 0SE 0SW 0NW.
34 KT... 90NE 90SE 60SW 90NW.

FORECAST VALID 15/1800Z 16.1N 41.1W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 45NE 45SE 30SW 45NW.
34 KT...100NE 100SE 75SW 100NW.

FORECAST VALID 16/1800Z 18.5N 44.0W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 60NE 60SE 45SW 60NW.
34 KT...120NE 120SE 90SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 17/1800Z 20.5N 46.5W
MAX WIND 80 KT...GUSTS 100 KT.

OUTLOOK VALID 18/1800Z 22.0N 49.5W
MAX WIND 85 KT...GUSTS 105 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 12.7N 30.7W

NEXT ADVISORY AT 14/0300Z

$$
FORECASTER BEVEN

[cycloneye]

[Josephine96]

Is it me or does it look like by Monday wanna be Helene may be turning back to the west?

[cycloneye]

Comments please post them at the TD 8 Main thread.

[Josephine96]

Sorry Luis.. no problem..

[cycloneye]

Sorry Luis.. no problem..

Ok no problem.

Ok Brent it's all yours now.

[Brent]

BULLETIN
TROPICAL STORM HELENE ADVISORY NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 PM AST WED SEP 13 2006

...TROPICAL DEPRESSION INTENSIFIES INTO TROPICAL STORM HELENE...

AT 1100 PM AST...0300Z...THE CENTER OF TROPICAL STORM HELENE WAS
LOCATED NEAR LATITUDE 13.3 NORTH...LONGITUDE 32.7 WEST OR ABOUT 565
MILES...910 KM...WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS.

TROPICAL STORM HELENE IS MOVING TOWARD THE WEST-NORTHWEST NEAR 22
MPH...35 KM/HR...AND THIS MOTION IS EXPECTED TO CONTINUE OVER THE
NEXT DAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. CONTINUED STRENGTHENING IS FORECAST DURING THE NEXT 24
HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.

REPEATING THE 1100 PM AST POSITION...13.3 N...32.7 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 22 MPH. MAXIMUM SUSTAINED WINDS...40
MPH. MINIMUM CENTRAL PRESSURE...1005 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 AM AST.

$$
FORECASTER AVILA/LANDSEA

[Brent]

TROPICAL STORM HELENE FORECAST/ADVISORY NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
0300 UTC THU SEP 14 2006

TROPICAL STORM CENTER LOCATED NEAR 13.3N 32.7W AT 14/0300Z
POSITION ACCURATE WITHIN 45 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 19 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 60NE 0SE 0SW 60NW.
12 FT SEAS.. 60NE 0SE 0SW 60NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 13.3N 32.7W AT 14/0300Z
AT 14/0000Z CENTER WAS LOCATED NEAR 13.1N 31.9W

FORECAST VALID 14/1200Z 13.7N 35.0W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 75NE 75SE 30SW 75NW.

FORECAST VALID 15/0000Z 14.7N 37.4W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 50NE 0SE 0SW 35NW.
34 KT...100NE 75SE 50SW 100NW.

FORECAST VALID 15/1200Z 15.9N 39.5W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 40NE 0SE 0SW 0NW.
50 KT... 60NE 40SE 0SW 40NW.
34 KT...120NE 100SE 60SW 100NW.

FORECAST VALID 16/0000Z 17.4N 41.0W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 60NE 40SE 25SW 40NW.
34 KT...120NE 100SE 60SW 100NW.

FORECAST VALID 17/0000Z 20.0N 43.5W
MAX WIND 90 KT...GUSTS 110 KT.
50 KT... 75NE 50SE 35SW 50NW.
34 KT...140NE 120SE 75SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 18/0000Z 21.5N 45.8W
MAX WIND 95 KT...GUSTS 115 KT.

OUTLOOK VALID 19/0000Z 22.5N 49.0W
MAX WIND 85 KT...GUSTS 105 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.3N 32.7W

NEXT ADVISORY AT 14/0900Z

$$
FORECASTER AVILA/LANDSEA

TROPICAL STORM HELENE DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 PM AST WED SEP 13 2006

INFRARED SATELLITE IMAGERY THIS EVENING INDICATES CONTINUED GRADUAL
DEVELOPMENT WITH A DISTINCT CURVED BAND ON THE NORTHWESTERN
SEMI-CIRCLE. BASED UPON UNANIMOUS DVORAK T-NUMBERS OF 2.5 AND
EARLIER AMSU INTENSITY ESTIMATES...THE INTENSITY IS ANALYZED AT 35
KT AND IS GIVEN THE NAME HELENE.

THE TROPICAL STORM APPEARS TO HAVE SPED UP WITH AN INITIAL MOTION OF
285/19...THOUGH THIS IS SOMEWHAT UNCERTAIN GIVEN THE SPREAD IN
POSITIONS. HELENE SHOULD CONTINUE WEST-NORTHWESTWARD FOR THE NEXT
DAY UNDER THE INFLUENCE OF A DEEP-LAYER RIDGE. BETWEEN 36 AND 72
HOURS...A MID TO UPPER TROUGH INDUCES A WEAKNESS IN THE RIDGE AND
THIS MAY ACT TO STEER THE SYSTEM TOWARD THE NORTHWEST. AFTER THIS
TROUGH BY-PASSES HELENE...A WEST-NORTHWESTWARD TRACK SHOULD RESUME
AT DAYS 4 AND 5. ALL RELIABLE GUIDANCE SHOWS THIS STAIR-STEP
SCENARIO...WITH NOGAPS BEING A MODEST OUTLIER TO THE SOUTHWEST OF
THE PACK. THE FORECAST TRACK IS NEAR THE MODEL CONSENSUS AND IS TO
THE RIGHT OF THE PREVIOUS FORECAST.

WHILE THERE IS A LARGE SAHARAN AIR LAYER TO THE NORTH AND WEST OF
HELENE...TOTAL PRECIPITABLE WATER ANALYSES FROM CIRA SUGGEST THAT
THIS VERY DRY AIR IS NOT REACHING HELENE'S INNER CORE. THE
SYSTEM'S PROJECTED TRACK SHOULD TAKE IT OVER WARM WATER...THROUGH
ABUNDANT MOISTURE AND INTO LIGHT VERTICAL SHEAR FOR THE NEXT THREE
DAYS. SHIPS AND THE FSU SUPER-ENSEMBLE THUS BRING HELENE UP TO
ABOUT 100 KT IN THREE DAYS. THE GFDL...ON THE OTHER HAND...IS
SUBSTANTIALLY WEAKER...LIKELY BECAUSE IT DEPICTS MORE SHEAR BEING
IMPARTED ON HELENE DUE TO THE AFOREMENTIONED MID TO UPPER TROUGH.
AT DAYS 4 AND 5...ALL GUIDANCE SUGGESTS THE SHEAR WILL PICK UP AND
LIMIT FURTHER INTENSIFICATION. THE INTENSITY FORECAST IS CLOSE
TO...BUT JUST BELOW...BOTH SHIPS AND THE FSU SUPER-ENSEMBLE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 14/0300Z 13.3N 32.7W 35 KT
12HR VT 14/1200Z 13.7N 35.0W 45 KT
24HR VT 15/0000Z 14.7N 37.4W 55 KT
36HR VT 15/1200Z 15.9N 39.5W 65 KT
48HR VT 16/0000Z 17.4N 41.0W 75 KT
72HR VT 17/0000Z 20.0N 43.5W 90 KT
96HR VT 18/0000Z 21.5N 45.5W 95 KT
120HR VT 19/0000Z 22.5N 49.0W 85 KT

$$
FORECASTER AVILA/LANDSEA

[AussieMark]

000
WTNT33 KNHC 140852
TCPAT3
BULLETIN
TROPICAL STORM HELENE ADVISORY NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 AM AST THU SEP 14 2006

...HELENE RACING WESTWARD WITH NO CHANGE IN STRENGTH...

AT 500 AM AST...0900Z...THE CENTER OF TROPICAL STORM HELENE WAS
LOCATED NEAR LATITUDE 13.7 NORTH...LONGITUDE 34.7 WEST OR ABOUT 695
MILES...1115 KM...WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS.

HELENE IS MOVING TOWARD THE WEST NEAR 22 MPH...35 KM/HR. A GRADUAL
TURN TOWARD THE WEST-NORTHWEST IS EXPECTED DURING THE NEXT 24
HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 85 MILES...140
KM...TO THE NORTH FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.

REPEATING THE 500 AM AST POSITION...13.7 N...34.7 W. MOVEMENT
TOWARD...WEST NEAR 22 MPH. MAXIMUM SUSTAINED WINDS...40 MPH.
MINIMUM CENTRAL PRESSURE...1005 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 AM AST.

$$
FORECASTER KNABB
-----------------------------------------------------------------------------------------------

000
WTNT43 KNHC 140849
TCDAT3
TROPICAL STORM HELENE DISCUSSION NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 AM EDT THU SEP 14 2006

HELENE REMAINS A FAIRLY DISORGANIZED TROPICAL STORM. THE
CONVECTIVE BAND SEEN LAST NIGHT IN THE NORTHWESTERN QUADRANT HAS
SPREAD OUT AND FRAGMENTED...THERE IS LITTLE OR NO DEEP
CONVECTION WITHIN ABOUT 60 N MI OF THE LOW-LEVEL CENTER...AND IN
GENERAL THE CLOUD TOPS HAVE WARMED OVERNIGHT. DVORAK T-NUMBERS ARE
UNCHANGED AND THE ADVISORY INTENSITY REMAINS 35 KT.

THE STORM CONTINUES TO RACE WESTWARD AT 280/19 AS IT CURRENTLY LIES
SOUTH OF THE CORE OF THE SUBTROPICAL RIDGE. THE SPREAD IN THE TRACK
GUIDANCE HAS BECOME RELATIVELY LARGE WITH THE MODELS FALLING INTO
TWO MAIN CAMPS. THE GFS...ITS ENSEMBLE MEAN...AND THE GFDL FORECAST
THE RIDGE TO THE NORTH TO WEAKEN QUITE RAPIDLY AND ALLOW THE STORM
TO TURN NORTHWESTWARD IN ABOUT 12 HOURS. THE UKMET AND NOGAPS
MAINTAIN THE RIDGE LONGER AND FORECAST HELENE TO MAINTAIN A
WEST-NORTHWESTWARD MOTION FOR ABOUT 48 MORE HOURS. ALL OF THE
MODELS FORECAST A NORTHWESTWARD MOTION...AT ABOUT HALF THE CURRENT
FORWARD SPEED...OVER THE CENTRAL ATLANTIC DURING DAYS 3-5. BY THAT
TIME...HOWEVER...THE TRACK GUIDANCE ENVELOPE IS MORE THAN 300 MILES
WIDE...SO THE TRACK FORECAST AT THOSE LONG RANGES IS QUITE
UNCERTAIN. THE NEW OFFICIAL TRACK FORECAST IS MOVED TO THE LEFT OF
THE PREVIOUS ADVISORY...BUT NOT AS FAR AS THE MODEL CONSENSUS.

HELENE CONTINUES IN ITS STRUGGLE TO INTENSIFY...PROBABLY BECAUSE OF
ITS LARGE SIZE AND THE FAST FORWARD MOTION. IT IS ASSUMED THAT THE
CONVECTION WILL SOON CONSOLIDATE NEAR THE CIRCULATION CENTER AND
ALLOW FOR MORE STEADY STRENGTHENING DURING THE NEXT DAY OR TWO.
THE IMPACTS OF THE NEARBY SAHARAN AIR LAYER ARE UNCERTAIN BUT COULD
END UP BEING AN ADDITIONAL INHIBITING FACTOR. LATER IN THE
FORECAST PERIOD...SINCE THE SSTS ALONG THE FORECAST TRACK WILL
REMAIN 27-28 CELSIUS AND THE GLOBAL MODELS INDICATE A WEAK SHEAR
ENVIRONMENT...ALL OF THE INTENSITY GUIDANCE ANTICIPATES HELENE TO
BECOME A HURRICANE. THE SHIPS MODEL HAS BACKED OFF A BIT AND NOW
MAKES HELENE NO STRONGER THAN ABOUT 85 KT THROUGH FIVE DAYS...WHICH
IS CLOSE TO THE LATEST GFDL SOLUTION. THE OFFICIAL FORECAST IS
ADJUSTED SLIGHTLY DOWNWARD TO BE IN AGREEMENT WITH THE GUIDANCE AT
THE LONGER RANGES...BUT IT IS BELOW SHIPS DURING THE FIRST 48 HOURS
OR SO.


FORECAST POSITIONS AND MAX WINDS

INITIAL 14/0900Z 13.7N 34.7W 35 KT
12HR VT 14/1800Z 14.1N 37.0W 40 KT
24HR VT 15/0600Z 15.2N 39.6W 50 KT
36HR VT 15/1800Z 16.5N 41.6W 60 KT
48HR VT 16/0600Z 17.8N 43.0W 70 KT
72HR VT 17/0600Z 20.0N 45.5W 80 KT
96HR VT 18/0600Z 22.0N 48.5W 85 KT
120HR VT 19/0600Z 24.0N 51.0W 85 KT

$$
FORECASTER KNABB

[Brent]

TROPICAL STORM HELENE FORECAST/ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1500 UTC THU SEP 14 2006

TROPICAL STORM CENTER LOCATED NEAR 13.4N 36.8W AT 14/1500Z
POSITION ACCURATE WITHIN 45 NM

PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1003 MB
MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT.
34 KT....... 75NE 0SE 0SW 75NW.
12 FT SEAS.. 75NE 0SE 0SW 75NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 13.4N 36.8W AT 14/1500Z
AT 14/1200Z CENTER WAS LOCATED NEAR 13.2N 36.0W

FORECAST VALID 15/0000Z 13.8N 39.1W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 75NE 0SE 0SW 75NW.

FORECAST VALID 15/1200Z 14.8N 42.0W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 30NE 0SE 0SW 30NW.
34 KT...100NE 40SE 40SW 100NW.

FORECAST VALID 16/0000Z 16.2N 44.1W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 30NE 0SE 0SW 0NW.
50 KT... 50NE 30SE 0SW 50NW.
34 KT...125NE 75SE 60SW 110NW.

FORECAST VALID 16/1200Z 17.5N 46.0W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 60NE 50SE 30SW 50NW.
34 KT...150NE 110SE 75SW 110NW.

FORECAST VALID 17/1200Z 19.5N 49.0W
MAX WIND 85 KT...GUSTS 105 KT.
50 KT... 60NE 50SE 30SW 50NW.
34 KT...150NE 110SE 75SW 110NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 18/1200Z 21.5N 51.0W
MAX WIND 90 KT...GUSTS 110 KT.

OUTLOOK VALID 19/1200Z 24.5N 53.0W
MAX WIND 90 KT...GUSTS 110 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.4N 36.8W

NEXT ADVISORY AT 14/2100Z

$$
FORECASTER COBB/BEVEN

[Brent]

TROPICAL STORM HELENE DISCUSSION NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 AM EDT THU SEP 14 2006

A QUIKSCAT AMBIGUITY ANALYSIS FROM 0802 UTC WAS HELPFUL IN LOCATING
THE CENTER WHICH WAS FURTHER SOUTH THAN THE PREVIOUS ADVISORY.
VISIBLE SATELLITE IMAGERY SUGGESTS HELENE IS SLOWLY BECOMING BETTER
ORGANIZED WITH INCREASING CURVATURE NOTED IN THE BANDING FEATURES.
SATELLITE INTENSITY ESTIMATES ARE 45 KT FROM TAFB...35 KT FROM SAB
AND AFWA. THE INITIAL INTENSITY IS INCREASED SLIGHTLY TO 40 KT FOR
THIS ADVISORY.

THE STORM CONTINUES TO RACE WESTWARD AT 275/20 AS IT CURRENTLY
REMAINS SOUTH OF THE SUBTROPICAL RIDGE. THE SPREAD IN THE TRACK
GUIDANCE REMAINS LARGE ESPECIALLY BEYOND 24 TO 36 HOURS.
AS NOTED IN THE PREVIOUS DISCUSSION...THE MODELS OFFER TWO
SOLUTIONS. THE GFS...ITS ENSEMBLE MEAN...AND THE GFDL ARE TO THE
RIGHT AND FORECAST THE RIDGE TO THE NORTH TO WEAKEN QUITE RAPIDLY
ALLOWING THE STORM TO TURN NORTHWESTWARD IN ABOUT 12 HOURS. THE
UKMET KEEPS THE SUBTROPICAL RIDGE AND MAINTAINS A WEST-NORTHWEST
TRACK LONGER. IN GENERAL ALL OF THE MODELS DECREASE THE FORWARD
SPEED BY HALF OVER THE CENTRAL ATLANTIC DURING DAYS 3-5. BY THAT
TIME THE TRACK FORECAST IS QUITE UNCERTAIN SINCE THE GUIDANCE
ENVELOPE IS MORE THAN 450 MILES WIDE. THE NEW OFFICIAL TRACK
FORECAST IS MOVED TO THE LEFT OF THE PREVIOUS ADVISORY...AND NOW
IN AGREEMENT WITH THE MODEL CONSENSUS.

THE INTENSIFICATION OF HELENE IS LIKELY TO BE SLOW INITIALLY BECAUSE
OF THE CURRENTLY BROAD CIRCULATION OF THE CYCLONE. CONVECTION SHOULD
EVENTUALLY CONSOLIDATE NEAR THE CIRCULATION CENTER AND ALLOW FOR
MORE STEADY STRENGTHENING DURING THE NEXT DAY OR TWO. SSTS ALONG
THE FORECAST TRACK ARE FORECAST TO REMAIN 27-28 CELSIUS AND THE
SYSTEM IS EXPECTED TO REMAIN IN A WEAK SHEAR ENVIRONMENT. THUS
HELENE IS FORECAST TO BECOME A HURRICANE BY 36 HOURS. THE SHIPS AND
GFDL MODELS INDICATE A PEAK INTENSITY OF 90-95 KT WHILE THE FSU
SUPERENSEMBLE INDICATES HELENE COULD BECOME A MAJOR HURRICANE.
THE OFFICIAL FORECAST IS LOWER THAN ALL THE GUIDANCE FOR THE FIRST
DAY OR TWO GIVEN THE CURRENT SLOW RATE OF INTENSIFICATION
THEREAFTER...THE FORECAST IS CLOSE TO THE SHIPS AND GFDL GUIDANCE
AND BRINGS HELENE TO A CATEGORY TWO HURRICANE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 14/1500Z 13.4N 36.8W 40 KT
12HR VT 15/0000Z 13.8N 39.1W 45 KT
24HR VT 15/1200Z 14.8N 42.0W 55 KT
36HR VT 16/0000Z 16.2N 44.1W 65 KT
48HR VT 16/1200Z 17.5N 46.0W 75 KT
72HR VT 17/1200Z 19.5N 49.0W 85 KT
96HR VT 18/1200Z 21.5N 51.0W 90 KT
120HR VT 19/1200Z 24.5N 53.0W 90 KT

$$
FORECASTER COBB/BEVEN

[Brent]

BULLETIN
TROPICAL STORM HELENE ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
1100 AM AST THU SEP 14 2006

...HELENE STRENGTHENING SLOWLY OVER THE FAR EASTERN ATLANTIC...

AT 1100 AM AST...1500Z...THE CENTER OF TROPICAL STORM HELENE WAS
LOCATED NEAR LATITUDE 13.4 NORTH...LONGITUDE 36.8 WEST OR ABOUT 835
MILES...1345 KM...WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS.

HELENE IS MOVING TOWARD THE WEST NEAR 20 MPH...32 KM/HR...A TURN TO
THE WEST-NORTHWEST IS EXPECTED IN THE NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER
GUSTS. GRADUAL STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 85 MILES...140 KM
FROM THE CENTER.

REPEATING THE 1100 AM AST POSITION...13.4 N...36.8 W. MOVEMENT
TOWARD...WEST NEAR 20 MPH. MAXIMUM SUSTAINED WINDS...45 MPH.
MINIMUM CENTRAL PRESSURE...1003 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM AST.

$$
FORECASTER COBB/BEVEN

[Brent]

BULLETIN
TROPICAL STORM HELENE ADVISORY NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 PM AST THU SEP 14 2006

...HELENE MOVING SLOWER...REMAINS FAR FROM LAND...

AT 500 PM AST...2100Z...THE CENTER OF TROPICAL STORM HELENE WAS
LOCATED NEAR LATITUDE 14.2 NORTH...LONGITUDE 37.6 WEST OR ABOUT 885
MILES...1420 KM...WEST OF THE SOUTHERNMOST CAPE VERDE ISLANDS.

HELENE IS MOVING TOWARD THE WEST-NORTHWEST NEAR 16 MPH...26 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE DURING THE NEXT
24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105 MILES...165 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB...29.62 INCHES.

REPEATING THE 500 PM AST POSITION...14.2 N...37.6 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 16 MPH. MAXIMUM SUSTAINED WINDS...45
MPH. MINIMUM CENTRAL PRESSURE...1003 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 PM AST.

$$
FORECASTER BROWN/FRANKLIN

TROPICAL STORM HELENE FORECAST/ADVISORY NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
2100 UTC THU SEP 14 2006

TROPICAL STORM CENTER LOCATED NEAR 14.2N 37.6W AT 14/2100Z
POSITION ACCURATE WITHIN 45 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 14 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1003 MB
MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT.
34 KT....... 90NE 45SE 0SW 90NW.
12 FT SEAS.. 90NE 45SE 0SW 90NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 14.2N 37.6W AT 14/2100Z
AT 14/1800Z CENTER WAS LOCATED NEAR 14.0N 37.0W

FORECAST VALID 15/0600Z 14.8N 39.7W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 90NE 45SE 0SW 90NW.

FORECAST VALID 15/1800Z 16.0N 42.1W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 30NE 0SE 0SW 30NW.
34 KT...100NE 45SE 45SW 100NW.

FORECAST VALID 16/0600Z 17.3N 44.4W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 25NE 25SE 0SW 0NW.
50 KT... 50NE 40SE 25SW 50NW.
34 KT...125NE 75SE 60SW 125NW.

FORECAST VALID 16/1800Z 18.5N 46.2W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 60NE 50SE 30SW 50NW.
34 KT...150NE 110SE 75SW 110NW.

FORECAST VALID 17/1800Z 20.5N 49.0W
MAX WIND 85 KT...GUSTS 105 KT.
50 KT... 60NE 50SE 30SW 50NW.
34 KT...150NE 110SE 75SW 110NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 18/1800Z 22.5N 51.0W
MAX WIND 90 KT...GUSTS 110 KT.

OUTLOOK VALID 19/1800Z 25.5N 54.0W
MAX WIND 90 KT...GUSTS 110 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 14.2N 37.6W

NEXT ADVISORY AT 15/0300Z

$$
FORECASTER BROWN/FRANKLIN

TROPICAL STORM HELENE DISCUSSION NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082006
500 PM EDT THU SEP 14 2006

THE OVERALL CLOUD PATTERN ASSOCIATED WITH HELENE HAS NOT CHANGED
MUCH SINCE THIS MORNING...AND THERE ARE NO DISTINCT CONVECTIVE
BANDING FEATURES. HOWEVER...THERE IS A SMALL BURST OF CONVECTION
THAT HAS RECENTLY DEVELOPED NEAR THE CENTER. SATELLITE INTENSITY
ESTIMATES REMAIN UNCHANGED FROM THIS MORNING AND THE INITIAL
INTENSITY WILL REMAIN 40 KT. A RATHER DISTINCT LOW-LEVEL
CIRCULATION BECAME APPARENT IN VISIBLE IMAGERY LATE THIS MORNING
WHICH WAS A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK...AND THIS
REQUIRED A SLIGHT ADJUSTMENT BOTH TO THE WORKING TRACK AND TO THE
SHORT TERM FORECAST.

HELENE HAS SLOWED DOWN DURING THE PAST 6 HOURS...BUT USING A LONGER
TERM 12 HOUR AVERAGE YIELDS AN INITIAL MOTION ESTIMATE OF 285/14.
HELENE IS MOVING WEST-NORTHWESTWARD SOUTH OF A MID-TO UPPER-LEVEL
RIDGE. THE GLOBAL MODELS IN GENERAL DEVELOP A BREAK IN THE RIDGE
IN A COUPLE DAYS BETWEEN 50W AND 60W...WHICH SHOULD IMPART A MORE
NORTHWESTWARD MOTION. HOWEVER...THERE REMAINS A FAIRLY LARGE
SPREAD IN THE MODELS AS TO WHEN THIS MAY OCCUR. THE GFS...ITS
ENSEMBLE MEAN...AND THE GFDL ARE TO THE RIGHT AND FORECAST THE
RIDGE TO WEAKEN MUCH SOONER. THE UKMET KEEPS THE RIDGE INTACT
LONGER AND THEREFORE IS ON THE LEFT SIDE OF THE GUIDANCE. THE
OFFICIAL TRACK IS CLOSE TO THE FSU SUPERENSEMBLE AND GUNA
MODEL CONSENSUS.

EVEN THOUGH THE OUTFLOW IS WELL ESTABLISHED AND HELENE IS IN A VERY
LOW SHEAR ENVIRONMENT...THE LARGE CIRCULATION STILL LACKS INNER
CORE CONVECTION. UNTIL THE INNER CORE DEVELOPS...STRENGTHENING IS
EXPECTED TO BE SLOW. THE NHC INTENSITY FORECAST SHOWS AN INCREASE
IN WIND SPEED MUCH LIKE THE SHIPS MODEL. LATE IN THE PERIOD GLOBAL
MODELS SUGGEST SOME INCREASING SHEAR WHICH COULD SLOW THE
INTENSIFICATION. ACCORDINGLY...THE OFFICIAL FORECAST IS NOT AS
AGGRESSIVE AS THE FSU SUPERENSEMBLE AT DAYS 4 AND 5.

THE WIND RADII WERE ADJUSTED OUTWARD BASED ON A RECENT REPORT OF
34 KT WINDS FROM A MOORED BUOY ABOUT 90 NM NORTHWEST OF HELENE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 14/2100Z 14.2N 37.6W 40 KT
12HR VT 15/0600Z 14.8N 39.7W 45 KT
24HR VT 15/1800Z 16.0N 42.1W 55 KT
36HR VT 16/0600Z 17.3N 44.4W 65 KT
48HR VT 16/1800Z 18.5N 46.2W 75 KT
72HR VT 17/1800Z 20.5N 49.0W 85 KT
96HR VT 18/1800Z 22.5N 51.0W 90 KT
120HR VT 19/1800Z 25.5N 54.0W 90 KT

$$
FORECASTER BROWN