ATL: PHILIPPE - Post - Tropical - Discussion

[Extratropical94]

Now TS Philippe:

BULLETIN
TROPICAL STORM PHILIPPE ADVISORY NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 PM AST SAT SEP 24 2011

...DEPRESSION BECOMES TROPICAL STORM PHILIPPE OVER THE FAR
EASTERN TROPICAL ATLANTIC...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...11.2N 27.9W
ABOUT 345 MI...550 KM SW OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

[cycloneye]

BULLETIN
TROPICAL STORM PHILIPPE ADVISORY NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 PM AST SAT SEP 24 2011

...DEPRESSION BECOMES TROPICAL STORM PHILIPPE OVER THE FAR
EASTERN TROPICAL ATLANTIC...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...11.2N 27.9W
ABOUT 345 MI...550 KM SW OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 PM AST...2100 UTC...THE CENTER OF TROPICAL STORM PHILIPPE WAS
LOCATED NEAR LATITUDE 11.2 NORTH...LONGITUDE 27.9 WEST. PHILIPPE IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 14 MPH...22 KM/H. THIS GENERAL
MOTION IS FORECAST TO CONTINUE THROUGH SUNDAY...FOLLOWED BY A
GRADUAL TURN TOWARD THE NORTHWEST WITH A DECREASE IN FORWARD SPEED
EXPECTED ON MONDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/H...WITH HIGHER
GUSTS. ADDITIONAL STRENGTHENING IS FORECAST DURING THE NEXT 48
HOURS.

TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 PM AST.

$$
FORECASTER STEWART

WTNT42 KNHC 242056
TCDAT2

TROPICAL STORM PHILIPPE DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 PM AST SAT SEP 24 2011

A CONVECTIVE BAND WRAPPING AT LEAST HALFWAY AROUND THE WEST SIDE OF
THE CYCLONE HAS DEVELOPED SINCE THE LAST ADVISORY. AS RESULT...THE
INITIAL INTENSITY IS INCREASED TO 35 KT...WHICH IS CONSISTENT WITH
THE 18Z TAFB DVORAK SATELLITE INTENSITY ESTIMATE OF T2.5/35 KT.
UPPER-LEVEL OUTFLOW IS GOOD TO FAIR IN ALL QUADRANTS AND HAS BEEN
SLOWLY IMPROVING.

THE INITIAL MOTION ESTIMATE IS 285/12. THERE IS NO SIGNIFICANT
CHANGE TO THE PREVIOUS TRACK REASONING. PHILIPPE IS EXPECTED TO
MOVE WEST-NORTHWESTWARD AROUND THE SOUTHERN PERIPHERY OF A STRONG
SUBTROPICAL RIDGE LOCATED TO THE NORTH OF THE CYCLONE. BY 48-72
HOURS...A BREAK IN THE RIDGE IS EXPECTED TO DEVELOP BETWEEN 40-45W
LONGITUDE AS A LARGE MID- TO UPPER-LEVEL TROUGH DIGS SOUTHEASTWARD
OVER THE CENTRAL AND EASTERN ATLANTIC. THIS SHOULD RESULT IN
PHILIPPE SLOWING DOWN AND GRADUALLY TURNING TOWARD THE NORTHWEST...
AND THEN TOWARD THE NORTH. THE OFFICIAL FORECAST WAS NUDGED
SLIGHTLY TO THE LEFT OF THE PREVIOUS TRACK DUE TO THE MORE WESTWARD
INITIAL POSITION...AND IS SIMILAR TO THE CONSENSUS MODEL TVCN.

THE BEST OPPORTUNITY FOR PHILIPPE TO STRENGTHEN IS EXPECTED TO BE
DURING THE NEXT 48 HOURS OR SO WHEN THE SHEAR IS THE LOWEST AND THE
THERMODYNAMICS ARE THE GREATEST. BY 72 HOURS...SOUTHWESTERLY
VERTICAL SHEAR IS FORECAST TO INCREASE TO ABOUT 15 KT...WHICH MAY
NOT BE ENOUGH TO SIGNIFICANTLY INHIBIT THE INTENSIFICATION PROCESS.
AS A RESULT...PHILIPPE IS EXPECTED TO REACH HURRICANE STATUS IN
48-72 HOURS...AND THEN LEVEL OFF SIMILAR TO THAT FORECAST BY THE
SHIPS AND LGEM STATISTICAL-DYNAMICAL MODELS. HOWEVER...IT IS WORTH
NOTING THAT THE GFDL AND EXPERIMENTAL HFIP INTENSITY MODELS MAKE
PHILIPPE A CATEGORY TWO HURRICANE BY DAYS 4 AND 5.

FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 11.2N 27.9W 35 KT 40 MPH
12H 25/0600Z 11.6N 29.6W 40 KT 45 MPH
24H 25/1800Z 12.5N 31.7W 45 KT 50 MPH
36H 26/0600Z 13.6N 33.3W 55 KT 65 MPH
48H 26/1800Z 14.8N 34.9W 65 KT 75 MPH
72H 27/1800Z 16.8N 36.8W 65 KT 75 MPH
96H 28/1800Z 19.5N 38.5W 65 KT 75 MPH
120H 29/1800Z 22.0N 39.0W 65 KT 75 MPH

$$
FORECASTER STEWART

[OURAGAN]

I don't see anything at 11,2N, may be at 10N/28w, moving westward, take a look at NRL

http://www.nrlmry.navy.mil/tc-bin/tc_ho ... ROD=1km_bw

[cycloneye]

Forecast to become a hurricane.

48H 26/1800Z 14.8N 34.9W 65 KT 75 MPH
72H 27/1800Z 16.8N 36.8W 65 KT 75 MPH
96H 28/1800Z 19.5N 38.5W 65 KT 75 MPH
120H 29/1800Z 22.0N 39.0W 65 KT 75 MPH

[OURAGAN]

I don't see any center at 11,2N / 27,9W, may be at 10N/28W, take a look at NRL

http://www.nrlmry.navy.mil/tc-bin/tc_ho ... ROD=1km_bw

[westwind]

well I'm keeping my eye on this one. The very early recurve might let this track into europe somewhere.

[Ptarmigan]

If Philippe becomes a hurricane, it would be the fourth this season.

[CrazyC83]

well I'm keeping my eye on this one. The very early recurve might let this track into europe somewhere.

Depending on how conditions are in the east-central Atlantic, such isn't exactly a far-fetched scenario.

[cycloneye]

00z Best Track

AL, 17, 2011092500, , BEST, 0, 112N, 285W, 35, 1006, TS

[brunota2003]

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

I do not see any hints toward RI (>30 knots in 24 hours) possibly occurring within the next 12 to 24 hours...in fact, I don't see anything pointing toward significant strengthening (in this case >20 knots) in the next 24 hours. I put RI at 3% and significant strengthening at 10%. 5 pm EDT tomorrow (Sunday, 25 Sept), I'll go with 45 or 50 knots.

However, this is always subject to change...as intensity forecasts always are.

[bexar]

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

Philippe really came as a surprise. Probably could pull a Julia.

however, it looks pretty bad right now.

[cycloneye]

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

[Fyzn94]

Nothing new in the 11PM advisory...

[Extratropical94]

BULLETIN
TROPICAL STORM PHILIPPE ADVISORY NUMBER 5
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 AM AST SUN SEP 25 2011

...PHILIPPE STRENGTHENS A LITTLE OVER THE EASTERN ATLANTIC...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...12.0N 29.8W
ABOUT 410 MI...660 KM WSW OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 AM AST...0900 UTC...THE CENTER OF TROPICAL STORM PHILIPPE WAS
LOCATED NEAR LATITUDE 12.0 NORTH...LONGITUDE 29.8 WEST. PHILIPPE IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 13 MPH...20 KM/H. A TURN
TOWARD THE NORTHWEST WITH A SLIGHT DECREASE IN FORWARD SPEED IS
EXPECTED TO BEGIN ON MONDAY.

MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 45 MPH...75 KM/H...
WITH HIGHER GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT
48 HOURS...AND PHILIPPE COULD BECOME A HURRICANE BY LATE MONDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB...29.65 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM AST.

$$
FORECASTER CANGIALOSI



TROPICAL STORM PHILIPPE DISCUSSION NUMBER 5
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 AM AST SUN SEP 25 2011

PHILIPPE HAS BECOME A LITTLE BETTER ORGANIZED DURING THE PAST
SEVERAL HOURS. THE CURVED BAND OVER THE WESTERN SEMICIRCLE HAS
WIDENED AND THE CENTRAL CONVECTION HAS EXPANDED AND DEEPENED.
SUBJECTIVE AND OBJECTIVE DVORAK CLASSIFICATIONS HAVE INCREASED AND
NOW SUPPORT AN INITIAL INTENSITY OF 40 KT. ADDITIONAL STRENGTHENING
OF THE CYCLONE IS LIKELY DURING THE NEXT COUPLE OF DAYS AS PHILIPPE
REMAINS IN FAVORABLE ATMOSPHERIC AND OCEANIC CONDITIONS...AND THE
OFFICIAL FORECAST BRINGS PHILIPPE TO HURRICANE STRENGTH BY 48
HOURS. AFTER THAT...THE CYCLONE WILL BE ENCOUNTERING AN INCREASE IN
SOUTHWESTERLY SHEAR AS IT MOVES OVER COOLER WATERS. THIS LESS
CONDUCIVE ENVIRONMENT SHOULD CAUSE SOME WEAKENING BY THE END OF THE
FORECAST PERIOD. THE OFFICIAL FORECAST IS ABOVE THE SHIPS AND LGEM
GUIDANCE BUT BELOW THE AGGRESSIVE GFDL MODEL.

THE TROPICAL STORM IS MOVING WEST-NORTHWESTWARD AT ABOUT 11 KT TO
THE SOUTH OF A NARROW RIDGE. THE MODELS ARE IN RELATIVELY GOOD
AGREEMENT IN SHOWING THE RIDGE WEAKEN IN RESPONSE TO A SERIES OF
SHORTWAVE TROUGHS MOVING ACROSS THE SUBTROPICAL EASTERN ATLANTIC.
THIS PATTERN WILL CAUSE PHILIPPE TO GRADUALLY TURN NORTHWARD OVER
THE EASTERN ATLANTIC IN THREE TO FOUR DAYS. THE OFFICIAL FORECAST
IS CLOSE TO THE MULTI-MODEL CONSENSUS AND WAS NUDGED WESTWARD AT
THE END OF THE FORECAST PERIOD...TRENDING TOWARD THE GFS AND ECMWF
MODELS.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0900Z 12.0N 29.8W 40 KT 45 MPH
12H 25/1800Z 12.8N 31.4W 45 KT 50 MPH
24H 26/0600Z 13.9N 33.2W 55 KT 65 MPH
36H 26/1800Z 14.9N 34.6W 60 KT 70 MPH
48H 27/0600Z 16.2N 35.6W 65 KT 75 MPH
72H 28/0600Z 18.5N 37.5W 60 KT 70 MPH
96H 29/0600Z 22.0N 38.5W 60 KT 70 MPH
120H 30/0600Z 25.0N 38.5W 55 KT 65 MPH

$$
FORECASTER CANGIALOSI

[dwsqos2]

My what a healthy and well-developed tropical cyclone this is.

This is obviously having dry/stable air issues as well. I have my doubts about it ever becoming a hurricane.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[cycloneye]

TROPICAL STORM PHILIPPE DISCUSSION NUMBER 6
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
1100 AM AST SUN SEP 25 2011

PHILIPPE HAS CHANGED LITTLE SINCE THE PREVIOUS ADVISORY...ALTHOUGH A
NEW BURST OF DEEP CONVECTION HAS RECENTLY DEVELOPED NEAR THE
CENTER. THE INITIAL INTENSITY IS BEING MAINTAINED AT 40 KT BASED ON
A BLEND OF SATELLITE INTENSITY ESTIMATES OF 45 KT FROM TAFB AND 30
KT FROM SAB.

THE INITIAL MOTION ESTIMATE IS 295/10 KT. THERE IS NO SIGNIFICANT
CHANGE TO THE PREVIOUS FORECAST TRACK REASONING. THE MODELS REMAIN
IN FAIRLY GOOD AGREEMENT ON PHILIPPE MOVING TOWARD A DEVELOPING
WEAKNESS IN THE SUBTROPICAL RIDGE TO THE NORTH...AND GRADUALLY
TURNING NORTHWESTWARD DURING THE NEXT 72 HOURS AND MOVING NORTHWARD
AFTER THAT. MOST OF THE MODELS ARE NOW INDICATING RECURVATURE TO
THE NORTHEAST BY DAY 5...EXCEPT FOR THE ECMWF MODEL. OUT OF RESPECT
FOR THAT MODEL...THE OFFICIAL FORECAST TRACK CONTINUES TO SHOW ONLY
A TURN TOWARD THE NORTH LATE IN THE FORECAST PERIOD. THE OFFICIAL
FORECAST TRACK IS BASICALLY AN EXTENSION OF THE PREVIOUS ADVISORY
AND IS CLOSE TO THE CONSENSUS MODELS TCVN AND TVCA.

MOST OF THE AVAILABLE MODEL GUIDANCE CONTINUES TO INDICATE THAT THE
MOST FAVORABLE SHEAR AND THERMODYNAMIC CONDITIONS WILL OCCUR DURING
THE NEXT 36 HOURS OR SO. AFTER THAT...PHILLIPE IS EXPECTED TO
EXPERIENCE INCREASING SOUTHWESTERLY SHEAR OF 20-25 KT AND BE MOVING
OVER SUB-27C SSTS AND INTO A SLIGHTLY DRIER AIRMASS. THE OFFICIAL
FORECAST CALLS FOR STRENGTHENING DURING THE NEXT 48 HOURS...WITH
GRADUAL WEAKENING EXPECTED AFTER THAT. THE OFFICIAL FORECAST TRACK
REMAINS ABOVE THE SHIPS AND LGEM GUIDANCE...BUT BELOW THE MORE
ROBUST GFDL AND HWRF MODELS...WHICH STILL INSIST THAT PHILLIPE WILL
BE NEAR CATEGORY 2 STRENGTH BY THE DAY 4-5 PERIOD.

FORECAST POSITIONS AND MAX WINDS

INIT 25/1500Z 12.5N 30.7W 40 KT 45 MPH
12H 26/0000Z 13.3N 32.1W 45 KT 50 MPH
24H 26/1200Z 14.4N 33.7W 55 KT 65 MPH
36H 27/0000Z 15.5N 34.9W 60 KT 70 MPH
48H 27/1200Z 16.7N 35.9W 65 KT 75 MPH
72H 28/1200Z 19.3N 37.6W 60 KT 70 MPH
96H 29/1200Z 22.5N 38.5W 60 KT 70 MPH
120H 30/1200Z 26.0N 38.5W 55 KT 65 MPH

$$
FORECASTER STEWART

[cycloneye]

Up to 60 mph

BULLETIN
TROPICAL STORM PHILIPPE ADVISORY NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 PM AST SUN SEP 25 2011

...PHILIPPE STRENGHTHENS OVER THE FAR EASTERN ATLANTIC...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...13.2N 31.7W
ABOUT 500 MI...805 KM WSW OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 305 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...997 MB...29.44 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 PM AST...2100 UTC...THE CENTER OF TROPICAL STORM PHILIPPE WAS
LOCATED NEAR LATITUDE 13.2 NORTH...LONGITUDE 31.7 WEST. PHILIPPE IS
MOVING TOWARD THE NORTHWEST NEAR 12 MPH...19 KM/H. A GRADUAL TURN
TOWARD THE NORTH-NORTHWEST WITH A SLIGHT DECREASE IN FORWARD SPEED
IS EXPECTED DURING THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 60 MPH...95 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...
AND PHILIPPE IS EXPECTED TO APPROACH HURRICANE STRENGTH BY LATE
MONDAY.

TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB...29.44 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 PM AST.

$$
FORECASTER ZELINSKY/STEWART

NNNN


TROPICAL STORM PHILIPPE DISCUSSION NUMBER 7
NWS NATIONAL HURRICANE CENTER MIAMI FL AL172011
500 PM AST SUN SEP 25 2011

THE APPEARANCE OF PHILIPPE ON VISIBLE IMAGERY HAS IMPROVED OVER THE
PAST FEW HOURS. CONVECTION HAS PERSISTED ALONG A CURVED BAND
LOCATED TO THE WEST AND SOUTH OF THE MAIN CENTER OF CIRCULATION...
AND A CDO-LIKE CENTRAL CONVECTIVE FEATURE HAS ALSO DEVELOPED.
DVORAK ESTIMATES OF INTENSITY HAVE INCREASED SINCE THE LAST
ADVISORY...AND A BLEND OF THESE ESTIMATES YIELDS AN INITIAL
INTENSITY OF 50 KT.

PHILIPPE IS MOVING TO THE NORTHWEST TOWARD A WEAKNESS IN THE
SUBTROPICAL RIDGE. THIS MOTION IS EXPECTED TO CONTINUE FOR THE
NEXT COUPLE OF DAYS...AND THERE IS GOOD AGREEMENT AMONG THE MODELS
THROUGH 48 HOURS. BEYOND THAT TIME...THE UNCERTAINTY INCREASES AS
SOME MODELS RECURVE THE TROPICAL CYCLONE TOWARDS THE NORTHEAST...
WHILE OTHERS ALLOW THE RIDGE TO REBUILD...RESULTING IN A MORE
WESTWARD TRACK. THIS DISCREPANCY IS LIKELY RELATED TO THE INTENSITY
OF PHILIPPE...AS A DEEPER AND STRONGER SYSTEM WILL LIKELY MOVE
FARTHER NORTH...WHILE A WEAKER SYSTEM WILL BE STEERED TO THE WEST
BY LOWER LEVEL EASTERLIES. OVERALL...THE GUIDANCE ENVELOPE HAS
SHIFTED WESTWARD...AND THE TRACK HAS BEEN NUDGED IN THAT DIRECTION
ACCORDINGLY.

THE ENVIRONMENT AROUND PHILIPPE CONTINUES TO BE CONDUCIVE FOR
INTENSIFICATION. THIS FAVORABLE ENVIRONMENT IS EXPECTED TO PERSIST
FOR THE NEXT 24 TO 36 HOURS. AFTER THAT...PHILIPPE WILL BEGIN
INTERACTING WITH AN UPPER-LEVEL TROUGH...WHICH SHOULD RESULT IN A
SUBSTANTIAL INCREASE IN THE VERTICAL WIND SHEAR. ADDITIONALLY...
THE CYCLONE WILL BEGIN MOVING OVER COOLER SSTS AND INTO A MORE
STABLE ENVIRONMENT. THE OFFICIAL INTENSITY FORECAST HAS NOT CHANGED
SUBSTANTIALLY...AND THE FORECAST STILL CALLS FOR PHILIPPE TO
APPROACH HURRICANE INTENSITY WITHIN THE NEXT COUPLE OF DAYS.

FORECAST POSITIONS AND MAX WINDS

INIT 25/2100Z 13.2N 31.7W 50 KT 60 MPH
12H 26/0600Z 14.0N 33.1W 55 KT 65 MPH
24H 26/1800Z 15.1N 34.7W 60 KT 70 MPH
36H 27/0600Z 16.1N 35.9W 65 KT 75 MPH
48H 27/1800Z 17.3N 36.9W 60 KT 70 MPH
72H 28/1800Z 20.0N 38.7W 55 KT 65 MPH
96H 29/1800Z 22.5N 39.5W 55 KT 65 MPH
120H 30/1800Z 25.0N 39.5W 50 KT 60 MPH

$$
FORECASTER ZELINSKY/STEWART

[Florida1118]

Already posted, I messed up

So, I will put a nice image of him instead.

[tolakram]

viewtopic.php?f=59&t=111968&p=2197325#p2197325

Posted as the advisory came out. Not sure what the commentary is all about but how about we don't do it.

[brunota2003]

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

I do not see any hints toward RI (>30 knots in 24 hours) possibly occurring within the next 12 to 24 hours...in fact, I don't see anything pointing toward significant strengthening (in this case >20 knots) in the next 24 hours. I put RI at 3% and significant strengthening at 10%. 5 pm EDT tomorrow (Sunday, 25 Sept), I'll go with 45 or 50 knots.

However, this is always subject to change...as intensity forecasts always are.

Well, my forecast held on perfectly. Between 5 pm 9/24 and 5 pm 9/25, Philippe only strengthened 15 knots (35 knots to 50 knots), below both significant and rapid strengthening. Of course, this is hardly surprising...and for now through 5 pm tomorrow, I feel chances of RI is less than 1%, and chances of significant strengthening is about 3%. I think Philippe will be at 60 knots at 5 pm tomorrow (increase in 10 knots). I don't really see Philippe getting much, if any, stronger than 60 knots.