EPAC: HENRIETTE - Post-Tropical

[TropicalAnalystwx13]

Hurricane Henriette

EP, 08, 2013080606, , BEST, 0, 135N, 1305W, 65, 991, HU, 64, NEQ, 15, 15, 15, 15, 1010, 170, 15, 0, 0, E, 0, , 0, 0, HENRIETTE, D,

[Kingarabian]

Can't wait to see visibles. Looks nice despite the nice being down.

[Kingarabian]

000
WTPZ43 KNHC 060840
TCDEP3

HURRICANE HENRIETTE DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
200 AM PDT TUE AUG 06 2013

AFTER A BRIEF CONVECTIVE RESPITE...A PRONOUNCED CDO FEATURE WITH
CLOUD TOPS OF -75C TO -80C HAS DEVELOPED OVER THE CENTER DURING THE
PAST 4 HOURS. VARIOUS MICROWAVE DATA DURING THE PAST 6 HOURS
INDICATE THAT A WELL-DEFINED AND VERTICALLY ALIGNED EYE HAS
DEVELOPED THROUGH A DEEP LAYER OF THE TROPICAL CYCLONE...AND WAS
EVEN BRIEFLY EVIDENT IN NIGHT TIME VISIBLE IMAGERY AROUND 0500 UTC.
SATELLITE INTENSITY ESTIMATES ARE T4.4/75 KT FROM UW-CIMSS ADT...
AND T4.0.65 KT FROM BOTH TAFB AND SAB. THEREFORE...HENRIETTE IS
UPGRADED TO A 65-KT HURRICANE...WHICH COULD BE CONSERVATIVE.

MICROWAVE SATELLITE IMAGERY INDICATES HENRIETTE HAS WOBBLED TOWARD
THE WEST-NORTHWEST DURING THE PAST 6 HOURS. HOWEVER...THIS IS
BELIEVED TO BE A TEMPORARY MOTION DUE TO RE-ORGANIZATION OF THE
INNER CORE AND DEVELOPMENT OF THE EYE....AND HENRIETTE IS EXPECTED
TO RESUME A NORTHWESTWARD MOTION LATER TODAY AS IT MOVES TOWARD A
WEAKNESS IN THE MID-PACIFIC SUBTROPICAL RIDGE LOCATED ALONG
136-137W LONGITUDE. BY 48-72 HOURS...THE RIDGE IS FORECAST TO BUILD
BACK WESTWARD AS THE UPPER-LEVEL TROUGH INDUCING THE WEAKNESS LIFTS
OUT TO THE NORTHEAST. AS THE RIDGE BUILDS WESTWARD...HENRIETTE IS
EXPECTED TO TURN WESTWARD OR EVEN WEST-SOUTHWESTWARD ON DAYS 4/5.
THE FORECAST TRACK IS CLOSE TO BOTH THE PREVIOUS ADVISORY TRACK AND
IS SIMILAR TO THE CONSENSUS MODEL TVCE.

ENVIRONMENTAL CONDITIONS ARE FAVORABLE FOR ADDITIONAL STRENGTHENING
TO OCCUR FOR AT LEAST THE NEXT 24 HOURS OR SO...ESPECIALLY GIVEN
THE VERY LOW VERTICAL WIND SHEAR CONDITIONS AND IMPRESSIVE OUTFLOW
PATTERN. HOWEVER...NONE OF THE RELIABLE MODEL GUIDANCE BRINGS
HENRIETTE MUCH ABOVE 75 KT...INCLUDING THE SHIPS AND LGEM MODELS.
THESE LOWER INTENSITY VALUES MAY BE THE RESULT OF THOSE MODELS
USING SST VALUES THAT ARE ABOUT 0.5C LOWER THAN WHAT IS NOTED IN
THE MOST RECENT SST ANALYSES. GIVEN THE 20-25 NMI DIAMETER EYE
NOTED IN A RECENT 0555Z AMSU MICROWAVE OVERPASS...THE INTENSITY IS
FORECAST TO INCREASE FOR THE NEXT 12-24 HOURS. BY 36 HOURS...
GRADUAL WEAKENING IS EXPECTED TO BEGIN AS HENRIETTE MOVES OVER OR
NEAR SUB-26C SSTS AND INTO A SLIGHTLY MORE STABLE AIRMASS.
HOWEVER...THE WEAKENING MIGHT NOT OCCUR AS QUICKLY OR AS MUCH AS
FORECAST DUE TO THE VERY LOW SHEAR CONDITIONS THAT ARE EXPECTED TO
EXIST THROUGHOUT THE ENTIRE FORECAST PERIOD. THE OFFICIAL FORECAST
IS SIMILAR TO THE PREVIOUS ONE...AND CLOSELY FOLLOWS THE SHIPS AND
LGEM MODELS.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0900Z 13.8N 130.9W 65 KT 75 MPH
12H 06/1800Z 14.7N 132.1W 75 KT 85 MPH
24H 07/0600Z 15.8N 133.7W 75 KT 85 MPH
36H 07/1800Z 16.7N 135.3W 70 KT 80 MPH
48H 08/0600Z 17.3N 137.0W 65 KT 75 MPH
72H 09/0600Z 17.8N 141.1W 55 KT 65 MPH
96H 10/0600Z 17.0N 145.3W 40 KT 45 MPH
120H 11/0600Z 16.8N 150.3W 30 KT 35 MPH

$$
FORECASTER STEWART

[Kingarabian]

Really nice AMSUB pass showing an increasingly organized core.

[Yellow Evan]

Will it become Cat 2 or 3? Or will it stop here like Gil.

[RL3AO]

Easily 75kts IMO.

[RL3AO]

Looking better and better. Think the NHC went too low with 70kts.

[Kingarabian]

Looking better and better. [/img]

You know what happened the last time we said that about Gil .

[Kingarabian]

06/1730 UTC 14.5N 131.9W T4.5/4.5 HENRIETTE

Code: Select all

 CI# /Pressure/ Vmax
                4.8 / 974.2mb/ 84.8kt

     
             Final T#  Adj T#  Raw T#
                4.8     4.8     3.9

[Kingarabian]

Another microwave pass:


Gil looked nicer in visible satellite imagery, but its core never came close to this.

[cycloneye]

Finnally a decent hurricane in EPAC.


HURRICANE HENRIETTE DISCUSSION NUMBER 14
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
200 PM PDT TUE AUG 06 2013

RECENT VISIBLE SATELLITE IMAGES SUGGEST THAT THE ORGANIZATION
OF THE SMALL HURRICANE HAS CONTINUED TO IMPROVE WITH A SMALL
EYE BECOMING EVIDENT. A SERIES OF MICROWAVE IMAGES DURING THE
PAST 12 HOURS OR SO HAVE CLEARLY SHOWN A CONTRACTING EYE.
THE INITIAL INTENSITY HAS BEEN INCREASED TO 80 KT...WHICH IS BETWEEN
THE SUBJECTIVE AND OBJECTIVE DVORAK ESTIMATES OF 77 KT
AND 85 KT...RESPECTIVELY. HENRIETTE IS EXPECTED TO REMAIN IN
AN ENVIRONMENT FAVORABLE FOR SOME ADDITIONAL INTENSIFICATION
DURING THE NEXT 12 TO 18 HOURS. AFTER THAT TIME...SLIGHTLY
COOLER SSTS AND A DRIER AND MORE STABLE AIR MASS SHOULD CAUSE A
GRADUAL WEAKENING TREND TO BEGIN. THE NHC INTENSITY FORECAST
IS A LITTLE ABOVE THE GUIDANCE DURING THE FIRST 12 TO 24 HOURS...
THEN LIES BETWEEN THE INTENSITY CONSENSUS AND THE SHIPS MODEL
THERAFTER.

HENRIETTE HAS BEEN MOVING ON A STEADY NORTHWESTWARD HEADING AT
ABOUT 9 KT TODAY. THE TRACK FORECAST REASONING REMAINS UNCHANGED
FROM THE PREVIOUS ADVISORY. HENRIETTE IS EXPECTED TO CONTINUE
NORTHWESTWARD FOR ANOTHER DAY OR SO...THEN TURN WESTWARD AS A
RIDGE RE-BUILDS TO THE NORTH OF THE CYCLONE. THE TRACK GUIDANCE IS
AGAIN IN FAIRLY GOOD AGREEMENT THROUGH 48 TO 72 HOURS...EXCEPT FOR
SOME FORWARD SPEED DIFFERENCES. THE NHC TRACK DURING THIS TIME
SPLITS THE DIFFERENCE BETWEEN THE SLOWER GFS AND THE FASTER ECMWF
AND LIES NEAR THE MODEL CONSENSUS. AS HENRIETTE WEAKENS AND
BECOMES A MORE SHALLOW CYCLONE LATER IN THE FORECAST PERIOD...IT IS
LIKELY TO TURN WEST-SOUTHWESTWARD IN THE LOW-LEVEL TRADEWIND FLOW.
THE TRACK GUIDANCE AT DAYS 4 AND 5 SHIFTED SOUTHWARD THIS CYCLE AND
THE OFFICIAL FORECAST HAS BEEN ADJUSTED IN THAT DIRECTION...BUT IT
REMAINS ALONG THE NORTHERN EDGE OF THE GUIDANCE ENVELOPE AT THOSE
TIMES.

FORECAST POSITIONS AND MAX WINDS

INIT 06/2100Z 14.7N 132.3W 80 KT 90 MPH
12H 07/0600Z 15.5N 133.6W 85 KT 100 MPH
24H 07/1800Z 16.4N 135.3W 80 KT 90 MPH
36H 08/0600Z 17.0N 137.1W 70 KT 80 MPH
48H 08/1800Z 17.3N 139.0W 60 KT 70 MPH
72H 09/1800Z 16.8N 143.0W 50 KT 60 MPH
96H 10/1800Z 16.0N 147.5W 35 KT 40 MPH
120H 11/1800Z 15.5N 152.5W 30 KT 35 MPH...POST-TROP/REMNT LOW

$$
FORECASTER BROWN

[Yellow Evan]

[Hurricane_Luis]

Hurricane Henriette

[Kingarabian]

[CrazyC83]

Now forecasting a Category 2 storm.

[vrif]

Here is the OSCAT 0806 2033Z pass.

[Kingarabian]

Here is the OSCAT 0806 2033Z pass.

Wow it appears to have a nice developing LLC!

[Yellow Evan]

First storm with a clear eye this year. About time.

[cycloneye]

00z Best Track at 80kts.

EP, 08, 2013080700, , BEST, 0, 149N, 1327W, 80, 981, HU

[CrazyC83]

07/0000 UTC 14.9N 132.7W T4.5/4.5 HENRIETTE -- East Pacific

No change.