CPAC: ANA - Post-Tropical

[Kingarabian]

WATCHES AND WARNINGS
--------------------
CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR HAWAII COUNTY.

[Yellow Evan]

WTPA35 PHFO 160238
TCPCP5

BULLETIN
TROPICAL STORM ANA ADVISORY NUMBER 10
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP022014
500 PM HST WED OCT 15 2014

...ANA MOVING WESTWARD...TROPICAL STORM WATCH ISSUED...


SUMMARY OF 500 PM HST...0300 UTC...INFORMATION
----------------------------------------------
LOCATION...14.1N 148.4W
ABOUT 590 MI...945 KM SE OF HILO HAWAII
ABOUT 800 MI...1285 KM SE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...998 MB...29.47 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR HAWAII COUNTY.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* HAWAII COUNTY

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

INTERESTS ELSEWHERE IN THE MAIN HAWAIIAN ISLANDS SHOULD MONITOR THE
PROGRESS OF ANA. WATCHES MAY BE REQUIRED FOR ADDITIONAL ISLANDS
LATER TONIGHT OR EARLY THURSDAY.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN
HONOLULU HAWAII.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 PM HST...0300 UTC...THE CENTER OF TROPICAL STORM ANA WAS
LOCATED NEAR LATITUDE 14.1 NORTH...LONGITUDE 148.4 WEST. ANA IS
MOVING TOWARD THE WEST NEAR 9 MPH...15 KM/H. A GRADUAL TURN TOWARD
THE NORTHWEST IS EXPECTED TONIGHT OR EARLY THURSDAY AND MAINTAIN
THIS MOTION THROUGH FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 65 MPH...100 KM/H...WITH HIGHER
GUSTS. ANA IS FORECAST TO GRADUALLY INTENSIFY AND MAY BECOME A
HURRICANE ON THURSDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 65 MILES...100 KM
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 998 MB...29.47 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE ON THE BIG
ISLAND OF HAWAII STARTING LATE FRIDAY.

SURF...LARGE SWELLS PRODUCED BY ANA ARE POSSIBLE OVER THE
EASTERN END OF THE MAIN HAWAIIAN ISLANDS STARTING LATE THURSDAY.
THESE LARGE SWELLS WILL CONTINUE TO SPREAD ACROSS THE ISLAND CHAIN
THROUGH THE WEEKEND. SURF PRODUCED BY THESE SWELLS MAY BE
POTENTIALLY DAMAGING ALONG SOME SHORELINES STARTING ON FRIDAY.

RAINFALL...HEAVY RAINFALL ASSOCIATED WITH ANA MAY REACH THE BIG
ISLAND OF HAWAII LATE FRIDAY. THESE RAINS COULD CAUSE
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...800 PM HST.
NEXT COMPLETE ADVISORY...1100 PM HST.

$$
FORECASTER KODAMA

[Kingarabian]

Weaker and further way from Oahu. But bullseye on Kauai.

[Yellow Evan]

Agree with everything the CPHC says.

WTPA45 PHFO 160306
TCDCP5

TROPICAL STORM ANA DISCUSSION NUMBER 10
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP022014
500 PM HST WED OCT 15 2014

ANA HAS DETERIORATED OVER THE PAST FEW HOURS AND THERE IS
SIGNIFICANT UNCERTAINTY OVER THE POSITION OF THE LOW LEVEL CENTER.
AN AMSU-B PASS FROM 2303 UTC SUGGESTS THAT THE CENTER REMAINS
DISPLACED NORTH OF THE DEEPEST CONVECTION...AND CENTER FIXES FROM
SAB AND JTWC AT 2330 UTC BOTH CAME IN AT 14.3N 148.0W. HOWEVER...LOW
CLOUD LINES IN THE VISIBLE IMAGES INDICATE THAT THE CENTER MAY HAVE
SHIFTED SLIGHTLY SOUTH CLOSER TO THE DEEP CONVECTION WITH PHFO
PLACING THE CENTER AT 13.9N 148.0W. THE INITIAL POSITION USES A
BLEND OF BOTH ESTIMATES...BUT THE CONFIDENCE IS RATHER LOW. IN
ADDITION TO THE CENTER UNCERTAINTIES...ANA/S APPEARANCE
HAS BECOME QUITE RAGGED IN THE LATEST SATELLITE IMAGES AND HAS
BECOME MUCH LESS SYMMETRIC. DVORAK INTENSITY ESTIMATES CAME IN AT 55
KT FROM ALL THREE FIX AGENCIES. AS A RESULT...THE INITIAL INTENSITY
HAS BEEN LOWERED TO 55 KT FOR THIS FORECAST PACKAGE...AND THIS MAY
BE GENEROUS.

THE INITIAL MOTION REMAINS UNCHANGED FROM THE PREVIOUS PACKAGE AT
270/8 KT. A DEEP LAYER RIDGE PROVIDING THE STEERING CURRENT IS
EXPECTED TO SHIFT AND PRODUCE A NORTHWESTWARD STEERING FLOW WHICH
WILL TURN ANA TOWARD THE HAWAIIAN ISLANDS. THE LATEST OBJECTIVE AIDS
REMAINS TIGHTLY CLUSTERED BUT HAVE SHIFTED TO THE WEST. AS A
RESULT...THE FORECAST HAS BEEN ADJUSTED SLIGHTLY WEST FROM THE
PREVIOUS FORECAST AND IS PARALLEL TO AND SLIGHTLY TO THE RIGHT OF
THE CONSENSUS. THE TRACK TAKES THE CENTER OF ANA SOUTH AND WEST OF
THE BIG ISLAND THEN NEAR KAUAI LATE THIS WEEKEND. FORWARD MOTION OF
THE CYCLONE IS EXPECTED TO SLOW LATE FRIDAY AND INTO SATURDAY AS
STEERING CURRENTS WEAKEN DUE TO THE PASSAGE OF A LOW PRESSURE
SYSTEM NORTH OF THE HAWAIIAN ISLANDS. THE NOAA GULFSTREAM IV
SAMPLED THE NEAR-STORM ENVIRONMENT EARLIER TODAY. DATA
COLLECTED DURING THE FLIGHT SHOULD HELP IMPROVE THIS EVENING/S
MODEL GUIDANCE.

THE INTENSITY FORECAST IS A CHALLENGE. ON ONE HAND...MORE THAN
ADEQUATE SEA SURFACE TEMPERATURES AND FAVORABLE FORECASTED VERTICAL
SHEAR CONDITIONS WOULD SUPPORT INTENSIFICATION TO A HURRICANE
THROUGH 48 HOURS. HWRF AND GHM ARE CONSISTENT WITH THIS REASONING.
HOWEVER...SHIPS AND LGEM ARE NO LONGER FORECASTING ANA TO BECOME A
HURRICANE. THE CURRENT DETERIORATION OF THE TROPICAL STORM IN THE
SATELLITE IMAGES DOES LEND CREDENCE TO THIS POSSIBILITY. THE
INTENSITY FORECAST FOR THIS PACKAGE LEANS TOWARD THE HWRF/GHM
SOLUTION AND STILL CALLS FOR ANA TO REACH HURRICANE INTENSITY
WITHIN 24 HOURS. HOWEVER...THE PEAK INTENSITY HAS BEEN LOWERED TO 70
KT INSTEAD OF 80 KT IN THE PREVIOUS FORECAST. IF ANA FAILS TO
REORGANIZE SOON...SUBSEQUENT INTENSITY FORECASTS MAY NEED TO BE
NUDGED DOWNWARD FURTHER.

NOTE THAT IT IS IMPORTANT FOR PEOPLE IN THE MAIN HAWAIIAN ISLANDS
NOT TO FOCUS TOO CLOSELY ON THE EXACT FORECAST TRACK OF ANA. WITH
AN AVERAGE 48 HOUR TRACK ERROR OF APPROXIMATELY 80 MILES...IT IS
STILL TOO SOON TO SAY WITH MUCH CERTAINTY WHICH ISLANDS WILL BE
MOST LIKELY TO EXPERIENCE THE WORST WEATHER. EVERYONE SHOULD BE
PREPARED FOR THE POSSIBILITY OF DIRECT IMPACTS FROM ANA. IT IS ALSO
IMPORTANT TO KEEP IN MIND THAT SIGNIFICANT IMPACTS FROM TROPICAL
CYCLONES CAN EXTEND WELL AWAY FROM THE CENTER.


FORECAST POSITIONS AND MAX WINDS

INIT 16/0300Z 14.1N 148.4W 55 KT 65 MPH
12H 16/1200Z 14.5N 149.8W 60 KT 70 MPH
24H 17/0000Z 15.3N 151.6W 65 KT 75 MPH
36H 17/1200Z 16.1N 153.4W 70 KT 80 MPH
48H 18/0000Z 17.2N 155.2W 70 KT 80 MPH
72H 19/0000Z 19.8N 157.1W 60 KT 70 MPH
96H 20/0000Z 21.0N 158.5W 55 KT 65 MPH
120H 21/0000Z 22.5N 160.5W 50 KT 60 MPH

$$
FORECASTER KODAMA

[Kingarabian]

Such a tough storm to forecast...

We'll see what the GFS says within an hour or so.

[Yellow Evan]

BTW, I think the CPHC has been doing a good job with this system all in all.

[Kingarabian]

BTW, I think the CPHC has been doing a good job with this system all in all.

Yes. A very good job.

Happy we Recon tomorrow.

[Kingarabian]

Despite all its troubles, it looks 10x better than Iselle did before it made landfall. Pretty scary how close it's going to get to the islands when you consider its size... Any wobble can change a lot of things.

[Yellow Evan]

It's starting to look better a little yes. And going a little more N. Given the angle of trajectories are different, I'd try not to compare this to Iselle.

[Kingarabian]

LLC a little bit more tucked in.

[AbcdeerHI]

Its probably my eyes playing tricks on me, but in the last few frames of visible imagery it looks like the convection has a curved signature. If i use the estimated center from CPHC 13.9N 148W. It would be the SE quadrant. Depending on how the next few hours play out, maybe this is the new llc.

[Kingarabian]

00z GFS is similar to the 18z GFS but it's closer to the Hawaiian Islands (more in-line with the CPHC track) and stronger than the 18zGFS, as it has a solid Cat.1 as it comes around the Big Island.

[Kingarabian]

Its probably my eyes playing tricks on me, but in the last few frames of visible imagery it looks like the convection has a curved signature. If i use the estimated center from CPHC 13.9N 148W. It would be the SE quadrant. Depending on how the next few hours play out, maybe this is the new llc.

Could be right as the LLC no longer looks to be north of the convection anymore. I wish Aric Dunn was here to explain things for us. He's exceptionally well in pin-pointing LLC's.

[Yellow Evan]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 16 OCT 2014 Time : 030000 UTC
Lat : 14:06:00 N Lon : 148:23:59 W


CI# /Pressure/ Vmax
3.6 / 995.9mb/ 57.0kt


Final T# Adj T# Raw T#
2.9 3.0 3.0

Center Temp : -60.9C Cloud Region Temp : -57.3C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : EAST PACIFIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : ON
Rapid Dissipation Flag : FLAG

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 50km
- Environmental MSLP : 1013mb

Satellite Name : GOES15
Satellite Viewing Angle : 22.7 degrees

Raw/Adjust ADT are higher than they were an hour or two ago.

[Alyono]

the CCC pattern seems to be transitioning to a curved band pattern

[Kingarabian]

the CCC pattern seems to be transitioning to a curved band pattern

What does a curved band pattern allude to?

And what do you think of the outflow to the South/SouthEast?

[Alyono]

the curved band if it fully transitions, would allow for intensification

[Kingarabian]

the curved band if it fully transitions, would allow for intensification

Thank you for the information.

[South Texas Storms]

the curved band if it fully transitions, would allow for intensification

Thank you for the information.

Yeah it's looking better this evening. It still has a decent chance of becoming a hurricane tomorrow.

[Kingarabian]

HWRF at 00z:



GFS at 00z: