EPAC: HENRIETTE - Post-Tropical

[Kingarabian]

Henriette is an absolute mess. The mid-level low seems dislocated from its low-level circulation, the convection is weak in general and very disorganized, and the center itself seems to be nearly exposed as a result of high northeasterly wind shear. It's a broad tropical cyclone as well, so I wouldn't expect quick intensification, even if conditions become more favorable as forecast. We will need to watch that disturbance east of Henriette as well...might complicate Henriette's intensity forecast.

[img]imagine[/img]

It's getting there. It has 2-3 days to intensify and is a mid-level TS already.

Yup. No one was mentioning any rapid intensification. It's getting there.

[Hurricaneman]

Its a typical large tropical cyclone as in it takes a longer time to wind up

[Yellow Evan]

Its a typical large tropical cyclone as in it takes a longer time to wind up

Yea, but the opposite is true sometimes as well. It takes longer for them to wind down, but Cosme earlier this year was an exception.

[Yellow Evan]

000
WTPZ43 KNHC 050858
TCDEP3

TROPICAL STORM HENRIETTE DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
200 AM PDT MON AUG 05 2013

THERE HAS BEEN LITTLE CHANGE IN THE OVERALL CONVECTIVE PATTERN OF
HENRIETTE SINCE THE PREVIOUS ADVISORY...AND SATELLITE INTENSITY
ESTIMATES ALSO REMAIN UNCHANGED. THE INTENSITY IS BEING HELD AT 45
KT...WHICH IS SUPPORTED BY A 0522Z ASCAT-A OVERPASS THAT SHOWED
40-KT WINDS ON THE SOUTH SIDE OF THE WELL-DEFINED CENTER. THE 34-KT
WIND RADII WERE ADJUSTED BASED ON THE ASCAT WIND DATA.

THERE HAVE BEEN SEVERAL WOBBLES IN THE MOTION OF HENRIETTE DURING
THE PAST 12 HOURS...BUT THE CYCLONE APPEARS TO HAVE SETTLED DOWN ON
A WESTWARD COURSE OF 275/06 BASED ON MICROWAVE SATELLITE FIXES.
HENRIETTE IS EXPECTED TO TURN TOWARD THE WEST-NORTHWEST LATER TODAY
AS IT MOVES TOWARD A WEAKNESS IN THE SUBTROPICAL RIDGE LOCATED
BETWEEN 135W-140W LONGITUDE. AS THE MID-/UPPER-LEVEL TROUGH
INDUCING THIS WEAKNESS LIFTS OUT TO THE NORTHEAST BY 72 HOURS...
THE CYCLONE IS EXPECTED TO TURN BACK TOWARD THE WEST ON DAYS 3-5 AS
THE RIDGE BUILDS BACK IN. THE NHC MODEL GUIDANCE MADE A NOTICEABLE
SHIFT TO THE NORTH ON THIS CYCLE...SO THE OFFICIAL FORECAST TRACK
WAS ALSO SHIFTED NORTHWARD AND LIES IN THE MIDDLE OF THE ENVELOPE.

HENRIETTE APPEARS POISED TO UNDERGO AT LEAST A TYPICAL RATE OF
INTENSIFICATION DURING THE NEXT 48 HOURS. A WEAK DISTURBANCE
LOCATED ABOUT 175 NMI TO THE EAST OF THE CYCLONE HAS BEEN STEADILY
WEAKENING AND MOVING CLOSER TO HENRIETTE OVER THE PAST 12 HOURS.
THAT SYSTEM SHOULD MORPH INTO AN OUTER RAIN BAND IN THE NORTHERN
SEMICIRCLE...ALLOWING THE PREVIOUSLY DIVERTED EQUATORIAL INFLOW TO
BE DRAWN INTO THE CENTER OF HENRIETTE. THIS INFLOW OF WARM UNSTABLE
AIR...COUPLED WITH 28C SSTS...ABUNDANT MID-LEVEL MOISTURE...AND LOW
VERTICAL SHEAR...SHOULD INITIATE THE INTENSIFICATION PROCESS LATER
TODAY. IN FACT...CONDITIONS ARE FAVORABLE FOR RAPID DEVELOPMENT TO
OCCUR AT SOME POINT DURING THE NEXT 2 DAYS. THE INTENSITY FORECAST
WAS INCREASED AND LIES CLOSE TO THE CONSENSUS MODEL ICON...BUT IS
BELOW THE HWRF MODEL...WHICH BRINGS HENRIETTE TO AT LEAST 90 KT IN
48 HOURS.

FORECAST POSITIONS AND MAX WINDS

INIT 05/0900Z 12.1N 127.9W 45 KT 50 MPH
12H 05/1800Z 12.5N 128.9W 50 KT 60 MPH
24H 06/0600Z 13.3N 130.4W 60 KT 70 MPH
36H 06/1800Z 14.3N 132.0W 70 KT 80 MPH
48H 07/0600Z 15.1N 133.7W 80 KT 90 MPH
72H 08/0600Z 16.3N 137.3W 75 KT 85 MPH
96H 09/0600Z 17.0N 141.0W 65 KT 75 MPH
120H 10/0600Z 17.5N 145.5W 50 KT 60 MPH

$$
FORECASTER STEWART

[cycloneye]

TROPICAL STORM HENRIETTE DISCUSSION NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
800 AM PDT MON AUG 05 2013

SATELLITE IMAGES INDICATE THAT THE OVERALL ORGANIZATION OF THE
TROPICAL CYCLONE HAS IMPROVED THIS MORNING. A BAND OF DEEP
CONVECTION NOW WRAPS AROUND THE SOUTH AND EAST PORTIONS
OF THE CIRCULATION AND BASED ON THE IMPROVED ORGANIZATION...
THE INITIAL INTENSITY IS RAISED TO 50 KT...A CONSENSUS
OF SUBJECTIVE AND OBJECTIVE DVORAK ESTIMATES.

HENRIETTE IS MOVING SLOWLY WESTWARD OR 270/4 KT. THE RIDGE TO THE
NORTH OF THE CYCLONE IS FORECAST TO CONTINUE WEAKENING IN RESPONSE
TO A MID- TO UPPER-LEVEL TROUGH THAT IS DEEPENING WELL WEST OF THE
COAST OF THE WESTERN UNITED STATES. THIS SHOULD CAUSE HENRIETTE TO
TURN WEST-NORTHWESTWARD LATER TODAY AND REMAIN ON THIS GENERAL
HEADING FOR THE NEXT 2 TO 3 DAYS. THE TRACK GUIDANCE ENVELOPE HAS
SHIFTED NORTHWARD THROUGH 48 HOURS. THE OFFICIAL FORECAST HAS
BEEN ADJUSTED IN THAT DIRECTION AND NOW LIES ON THE SOUTHERN EDGE OF
THE GUIDANCE ENVELOPE. AFTER 72 HOURS...THE TROUGH IS FORECAST
TO LIFT OUT WITH THE RIDGE BUILDING WESTWARD ONCE AGAIN. AS A
RESULT...HENRIETTE SHOULD TURN WESTWARD AND STAY ON THAT GENERAL
HEADING DURING THE 3- TO 5-DAY TIME PERIOD.

THE ENVIRONMENT AHEAD OF HENRIETTE APPEARS FAVORABLE FOR
STRENGTHENING DURING THE NEXT DAY OR SO. MODERATE EASTERLY SHEAR
THAT IS CURRENTLY OVER THE CYCLONE SHOULD DECREASE AS HENRIETTE
MOVES BENEATH AN UPPER-LEVEL RIDGE AXIS. DURING THAT TIME...THE
CYCLONE WILL BE OVER WARM WATERS...SO STEADY STRENGTHENING IS
ANTICIPATED. IN 36 TO 48 HOURS...HENRIETTE IS FORECAST TO CROSS
A TONGUE OF COOLER WATERS...WHICH IS LIKELY TO HALT THE
INTENSIFICATION PROCESS. THE SHEAR IS FORECAST TO REMAIN LIGHT
WHEN THE CYCLONE TURN WESTWARD IN ABOUT 3 DAYS...AND MOVES ALONG
THE 26 DEGREE CELSIUS ISOTHERM. THE COOLER WATERS AND A MORE
STABLE AIRMASS ARE LIKELY TO CAUSE GRADUAL WEAKENING...HOWEVER IF
HENRIETTE MOVES NORTH OF THE FORECAST TRACK IT COULD WEAKEN MUCH
FASTER THAN SHOWN BELOW. CONVERSELY...IF HENRIETTE IS SOUTH OF THE
FORECAST TRACK... THE RATE OF WEAKENING COULD BE SLOWER.



FORECAST POSITIONS AND MAX WINDS

INIT 05/1500Z 12.1N 128.2W 50 KT 60 MPH
12H 06/0000Z 12.6N 129.2W 60 KT 70 MPH
24H 06/1200Z 13.6N 130.7W 65 KT 75 MPH
36H 07/0000Z 14.7N 132.4W 75 KT 85 MPH
48H 07/1200Z 15.6N 134.1W 70 KT 80 MPH
72H 08/1200Z 16.9N 137.7W 65 KT 75 MPH
96H 09/1200Z 17.0N 141.5W 60 KT 70 MPH
120H 10/1200Z 17.0N 146.0W 50 KT 60 MPH

$$
FORECASTER BROWN

[RL3AO]

Looks good on microwave. Signs of a midlevel eyewall.

[cycloneye]

18z Best Track up to 55kts.

EP, 08, 2013080518, , BEST, 0, 124N, 1285W, 55, 996, TS

[Cyclenall]

A WEAK DISTURBANCE
LOCATED ABOUT 175 NMI TO THE EAST OF THE CYCLONE HAS BEEN STEADILY
WEAKENING AND MOVING CLOSER TO HENRIETTE OVER THE PAST 12 HOURS.
THAT SYSTEM SHOULD MORPH INTO AN OUTER RAIN BAND IN THE NORTHERN
SEMICIRCLE...ALLOWING THE PREVIOUSLY DIVERTED EQUATORIAL INFLOW TO
BE DRAWN INTO THE CENTER OF HENRIETTE.

I've never heard this before. A disturbance becoming an outer band in another TC? A loop of that process would be awesome.

Last I last checked of Henriette when it first formed, the NHC forecast it to only get to 35 knots, now 75-80 knots?!?!? What? Reminds me of Kirk in the Atlantic, a weak TS forecast became a major hurricane.

[RL3AO]

Unless it pulls a Gil, it should easily become the strongest storm of the season so far. I think it will peak around 85 to 95kts.

[TropicalAnalystwx13]

Henriette looks so much better this afternoon. Some slight northeasterly shear is still evident, but the system has developed a central dense overcast and banding is decent in all nearly every quadrant. In addition, a 1414z microwave pass indicated a large eye associated with the system. It's well on its way to hurricane intensity, and should attain such late tonight or in the morning if it continues to intensify. Rapid intensification still looks unlikely, but I definitely agree with the above. Henriette may become the strongest system of the season...but small changes in the environment could hurt it (a.k.a Gil).

http://www.ssd.noaa.gov/PS/TROP/floater ... 0-lalo.jpg

[cycloneye]

TROPICAL STORM HENRIETTE DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
200 PM PDT MON AUG 05 2013

THE SMALL TROPICAL CYCLONE CONTINUES TO STRENGTHEN THIS AFTERNOON.
VISIBLE SATELLITE IMAGES SHOW A CENTRAL DENSE OVERCAST FEATURE...
WITH RECENT HINTS OF AN EYE. AN EARLIER 1414 UTC SSMIS MICROWAVE
IMAGE REVEALED A MID-LEVEL EYE WITH A FAIRLY WELL-DEFINED LOW-LEVEL
RING. DVORAK INTENSITY ESTIMATES FROM BOTH TAFB AND SAB SUPPORT AN
INITIAL INTENSITY OF 55 KT. LOW SHEAR AND WARM WATERS AHEAD OF
HENRIETTE DURING THE NEXT DAY OR SO SHOULD ALLOW FOR CONTINUED
INTENSIFICATION...AND THE TROPICAL CYCLONE IS FORECAST TO BECOME A
HURRICANE TONIGHT OR EARLY TUESDAY. IN 24 TO 36 HOURS...HENRIETTE
WILL BE CROSSING A TONGUE OF COOLER SSTS THAT WILL LIKELY SLOW OR
HALT THE STRENGTHENING. LATER IN THE PERIOD... COOLER WATERS AND A
MORE STABLE AIR MASS ARE EXPECTED TO CAUSE GRADUAL WEAKENING. IF
HENRIETTE MOVES NORTH OF THE CURRENT FORECAST TRACK IT WOULD
ENCOUNTER MUCH COOLER SSTS AND LIKELY WEAKEN FASTER THAN INDICATED
BELOW.

HENRIETTE HAS MADE ITS MUCH ANTICIPATED WEST-NORTHWESTWARD TURN. IT
HAS ALSO GAINED SOME FORWARD SPEED WITH AN INITIAL MOTION OF 290/8
KT. HENRIETTE SHOULD MOVE WEST-NORTHWESTWARD TO NORTHWESTWARD
TOWARD A BREAK IN THE SUBTROPICAL RIDGE DURING THE NEXT COUPLE OF
DAYS. THE TRACK GUIDANCE HAS COME INTO MUCH BETTER AGREEMENT ON
THIS CYCLE...AND THE NHC TRACK HAS BEEN ADJUSTED NORTHWARD ONCE
AGAIN TO BE NEAR THE MIDDLE OF THE GUIDANCE ENVELOPE. AFTER 48
HOURS...THE MID-LATITUDE TROUGH THAT IS PRODUCING THE WEAKNESS IN
THE RIDGE IS EXPECTED TO LIFT OUT WITH THE RIDGE BUILDING WESTWARD
ONCE AGAIN. THIS SHOULD CAUSE HENRIETTE TO TURN BACK TOWARD THE
WEST DURING THE 3- TO 5-DAY TIME PERIOD. AS HENRIETTE WEAKENS AND
BECOMES A SHALLOW CYCLONE...IT IS LIKELY TO MOVE MORE QUICKLY
WESTWARD IN THE BRISK LOW-LEVEL EASTERLY TRADES OVER THE CENTRAL
PACIFIC.

FORECAST POSITIONS AND MAX WINDS

INIT 05/2100Z 12.8N 129.0W 55 KT 65 MPH
12H 06/0600Z 13.6N 130.0W 65 KT 75 MPH
24H 06/1800Z 14.8N 131.5W 70 KT 80 MPH
36H 07/0600Z 15.8N 133.1W 75 KT 85 MPH
48H 07/1800Z 16.7N 134.8W 70 KT 80 MPH
72H 08/1800Z 17.5N 138.5W 60 KT 70 MPH
96H 09/1800Z 17.3N 142.5W 50 KT 60 MPH
120H 10/1800Z 17.0N 147.0W 40 KT 45 MPH

$$
FORECASTER BROWN

[WeatherGuesser]

AND THE NHC TRACK HAS BEEN ADJUSTED NORTHWARD ONCE
AGAIN TO BE NEAR THE MIDDLE OF THE GUIDANCE ENVELOPE. AFTER 48
HOURS...THE MID-LATITUDE TROUGH THAT IS PRODUCING THE WEAKNESS IN
THE RIDGE IS EXPECTED TO LIFT OUT WITH THE RIDGE BUILDING WESTWARD
ONCE AGAIN. THIS SHOULD CAUSE HENRIETTE TO TURN BACK TOWARD THE
WEST DURING THE 3- TO 5-DAY TIME PERIOD.

Are we thinking Hawaii again? Or will it die before then?

[RL3AO]

The CPac is very unfavorable. Hard for anything more than a sheared depression to make it to Hawaii.

[Yellow Evan]

AND THE NHC TRACK HAS BEEN ADJUSTED NORTHWARD ONCE
AGAIN TO BE NEAR THE MIDDLE OF THE GUIDANCE ENVELOPE. AFTER 48
HOURS...THE MID-LATITUDE TROUGH THAT IS PRODUCING THE WEAKNESS IN
THE RIDGE IS EXPECTED TO LIFT OUT WITH THE RIDGE BUILDING WESTWARD
ONCE AGAIN. THIS SHOULD CAUSE HENRIETTE TO TURN BACK TOWARD THE
WEST DURING THE 3- TO 5-DAY TIME PERIOD.

Are we thinking Hawaii again? Or will it die before then?

It will likely be long go IMO. Henriette is moving slowly.

[cycloneye]

00z Best Track up to 60kts.

EP, 08, 2013080600, , BEST, 0, 132N, 1296W, 60, 995, TS

[RL3AO]

[cycloneye]

TROPICAL STORM HENRIETTE DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082013
800 PM PDT MON AUG 05 2013

HENRIETTE IS APPROACHING HURRICANE STRENGTH THIS EVENING WITH A
CENTRAL DENSE OVERCAST FEATURE GROWING NEAR THE CENTER. MICROWAVE
DATA SHOW THAT THE CENTRAL FEATURES CONTINUE TO BECOME BETTER
DEFINED...WITH WHAT RESEMBLES AN EYEWALL PRESENT ON THE LATEST
PASSES. DUE TO THE INCREASE IN INNER-CORE ORGANIZATION...THE
INITIAL WIND SPEED IS SET TO 60 KT. FURTHER STRENGTHENING SEEMS
LIKELY WITH LIGHT SHEAR AND WARM WATER IN THE PATH OF THE STORM FOR
THE NEXT DAY OR SO. THEREAFTER...ALTHOUGH THE SHEAR REMAINS LOW...
HENRIETTE WILL BE HEADING INTO MORE STABLE AIR AND ACROSS COOLER
WATERS...WHICH SHOULD START A WEAKENING TREND. THE OFFICIAL
FORECAST IS CLOSE TO THE PREVIOUS ONE...RELYING ON A BLEND OF THE
TREND OF THE PREVIOUS FORECAST AND THE INTENSITY CONSENSUS.

THE LATEST MICROWAVE FIXES SHOW THAT HENRIETTE IS MOVING FASTER AND
HAS TURNED TOWARD THE NORTHWEST...305/10. THIS GENERAL TRACK IS
FORECAST FOR THE NEXT DAY OR SO WHILE THE CYCLONE MOVES AROUND THE
SOUTHWESTERN PORTION OF A MID-LEVEL RIDGE. THIS RIDGE IS EXPECTED
TO BUILD TO THE NORTHWEST OF HENRIETTE AFTER THAT TIME...CAUSING
THE STORM TO TURN TOWARD THE WEST WITHIN A FEW DAYS. THIS SCENARIO
IS WELL SUPPORTED BY THE TRACK GUIDANCE AND VERY LITTLE CHANGE WAS
MADE TO THE PREVIOUS FORECAST. THE LATEST NHC FORECAST LIES CLOSE
TO THE MULTI-MODEL CONSENSUS AND THE FLORIDA STATE SUPERENSEMBLE.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0300Z 13.5N 130.0W 60 KT 70 MPH
12H 06/1200Z 14.4N 131.3W 70 KT 80 MPH
24H 07/0000Z 15.6N 132.9W 75 KT 85 MPH
36H 07/1200Z 16.6N 134.5W 70 KT 80 MPH
48H 08/0000Z 17.3N 136.2W 65 KT 75 MPH
72H 09/0000Z 17.9N 139.9W 55 KT 65 MPH
96H 10/0000Z 17.1N 144.1W 40 KT 45 MPH
120H 11/0000Z 17.0N 149.0W 30 KT 35 MPH

$$
FORECASTER BLAKE

[Yellow Evan]

FURTHER STRENGTHENING SEEMS
LIKELY WITH LIGHT SHEAR AND WARM WATER IN THE PATH OF THE STORM FOR
THE NEXT DAY OR SO. THEREAFTER...ALTHOUGH THE SHEAR REMAINS LOW...
HENRIETTE WILL BE HEADING INTO MORE STABLE AIR AND ACROSS COOLER
WATERS...WHICH SHOULD START A WEAKENING TREND.

If shear is low, could it pull a Daniel 12 and continue intensifying or at least hold it's intensity. I don't think so.

[Kingarabian]

Code: Select all

CI# /Pressure/ Vmax
                4.3 / 983.8mb/ 72.2kt

     
             Final T#  Adj T#  Raw T#
                4.3     4.3     3.2

 Center Temp : -53.4C    Cloud Region Temp : -60.1C

 Scene Type : UNIFORM CDO CLOUD REGION w/ MW EYE

[Yellow Evan]

Code: Select all

CI# /Pressure/ Vmax
                4.3 / 983.8mb/ 72.2kt

     
             Final T#  Adj T#  Raw T#
                4.3     4.3     3.2

 Center Temp : -53.4C    Cloud Region Temp : -60.1C

 Scene Type : UNIFORM CDO CLOUD REGION w/ MW EYE

I'm not 100% convinced this is a cane though.