CPAC: NIALA - Post-Tropical

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Re: CPAC: NIALA - Tropical Storm

#61 Postby Kingarabian » Fri Sep 25, 2015 8:24 pm

AbcdeerHI wrote:
Kingarabian wrote:Why would they go with Dvorak when visible satellite says otherwise? Not a single mention of the intermittent eye.

My guess would be theyre look for consistency raher then jumping the gun in the short term. As i write this the "intermittent eye" has dissipated. Im sure this will be mentioned in the 5pm discussion.

I do wonder if Naiala gets stronger than anticipated will the track shift to the right? If so, does that mean stronger shear and quicker decoupling or possibly traveling farther north then currently predicted and more islands get caught in the remnants?


But that's why it's called an intermittent eye. It's not consistent but it's there, meaning that the storm has intensified to the point where the eye can clear. And when there's an eye, it means that the storm is hurricane.

But I would see them going with 60kts if microwave remains dodgy.

I think the track is dependent on storm intensity. 18z GFS kept it stronger and shifted more right before it got decapitated by the shear. 12z Euro shows it intact under the big island but keeps it moving west. Don't know how that makes sense. Maybe it gets decoupled?
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#62 Postby Kingarabian » Fri Sep 25, 2015 8:53 pm

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#63 Postby Yellow Evan » Sat Sep 26, 2015 1:44 am

WTPA31 PHFO 260606
TCPCP1

BULLETIN
TROPICAL STORM NIALA INTERMEDIATE ADVISORY NUMBER 5A
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP062015
800 PM HST FRI SEP 25 2015

...NIALA CONTINUING TO APPROACH HAWAII FROM THE SOUTHEAST...


SUMMARY OF 800 PM HST...0600 UTC...INFORMATION
----------------------------------------------
LOCATION...16.6N 150.9W
ABOUT 345 MI...555 KM SE OF HILO HAWAII
ABOUT 555 MI...895 KM SE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES


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

NONE.

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 TROPICAL STORM NIALA.

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 800 PM HST...0600 UTC...THE CENTER OF TROPICAL STORM NIALA WAS
LOCATED NEAR LATITUDE 16.6 NORTH...LONGITUDE 150.9 WEST. NIALA IS
MOVING TOWARD THE NORTHWEST NEAR 7 MPH...11 KM/H. THIS MOTION IS
EXPECTED TO CONTINUE THROUGH TONIGHT...FOLLOWED BY A TURN TOWARD
THE WEST AND A SLOWING OF THE FORWARD MOTION SATURDAY AND SUNDAY.
ON THE FORECAST TRACK...THE CENTER OF NIALA WILL PASS 100 TO 150
MILES SOUTH OF THE BIG ISLAND LATER SUNDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS POSSIBLE THROUGH EARLY SATURDAY...
FOLLOWED BY WEAKENING SATURDAY NIGHT AND SUNDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 80 MILES...130 KM
FROM THE CENTER. REMEMBER THAT DAMAGING EFFECTS FROM TROPICAL
CYCLONES CAN EXTEND WELL AWAY FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB...29.50 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...STORM TOTAL RAINFALL OF 6 TO 12 INCHES...WITH
ISOLATED MAXIMUM AMOUNTS TO 16 INCHES...ARE EXPECTED WITHIN THE
WATCH AREA. THESE RAINFALL AMOUNTS COULD CAUSE LIFE-THREATENING
FLASH FLOODS...AS WELL AS ROCKSLIDES AND MUDSLIDES.

SURF...SWELLS ASSOCIATED WITH TROPICAL STORM NIALA WILL PRODUCE
LARGE SURF ALONG SOUTHEAST FACING SHORES OF MAINLY THE BIG ISLAND
THIS WEEKEND AND CONTINUING INTO EARLY NEXT WEEK.

WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE ON THE BIG ISLAND ON
SUNDAY.


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

$$
FORECASTER R BALLARD
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#64 Postby Kingarabian » Sat Sep 26, 2015 3:06 am

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#65 Postby Kingarabian » Sat Sep 26, 2015 4:13 am

Code: Select all

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

             ----- Current Analysis -----
     Date :  26 SEP 2015    Time :   083000 UTC
      Lat :   16:45:03 N     Lon :  151:09:53 W

     
                CI# /Pressure/ Vmax
                3.8 / 990.0mb/ 61.0kt

     
             Final T#  Adj T#  Raw T#
                3.8     4.0     4.0
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#66 Postby Kingarabian » Sat Sep 26, 2015 4:47 am

WTPA41 PHFO 260916
TCDCP1

TROPICAL STORM NIALA DISCUSSION NUMBER 6
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP062015
1100 PM HST FRI SEP 25 2015

INCREASING WESTERLY SHEAR IS HAVING AN IMPACT ON NIALA. UPPER LEVEL
OUTFLOW IS VIRTUALLY NONEXISTENT TO THE NORTHWEST OF THE CYCLONE...
AND THE LOW LEVEL CIRCULATION CENTER IS BECOMING MORE DIFFICULT TO
LOCATED IN CONVENTIONAL SATELLITE IMAGERY. HOWEVER...A HELPFUL 0403
UTC SSMIS PASS SHOWED THAT DESPITE THE DEGRADED OVERALL
PRESENTATION...THE CENTRAL CORE REMAINS LARGELY INTACT FOR THE TIME
BEING WITH DEEP CONVECTION STILL WRAPPING AROUND THE SUSPECTED LOW
LEVEL CENTER. THE SATELLITE INTENSITY ESTIMATES WERE A UNANIMOUS 3.0
AND SO THE ADVISORY INTENSITY IS BEING KEPT AT 45 KT.

THE INITIAL MOTION IS 325/7. NIALA IS STILL GAINING LATITUDE AS IT
FEELS THE INFLUENCE OF A LARGE MID-TO-UPPER LEVEL TROUGH EXTENDING
FAR TO THE NORTHEAST OF HAWAII. THERE IS ALSO SOME WESTWARD
COMPONENT TO THE MOTION OWING TO STRONG HIGH PRESSURE ROUGHLY
1500 MILES NORTH OF HAWAII. NIALA IS ENCOUNTERING WESTERLY
SHEAR...BETWEEN 20 AND 30 KT ON THE CIMSS DEEP LAYER WIND SHEAR
ANALYSIS...WHICH WILL ONLY INCREASE AS THE STORM PUSHES FARTHER
TOWARD THE NORTHWEST. SOONER OR LATER THE DEEP CONVECTION WILL
SEPARATE FROM THE LOW LEVEL CIRCULATION CENTER...CAUSING NIALA TO
THEN BE STEERED MORE BY THE LOW LEVEL FLOW. IT IS DIFFICULT TO SAY
EXACTLY WHEN THIS WILL HAPPEN...LEADING TO THE UNCERTAINTY IN THE
FORECAST. HOWEVER...THE GUIDANCE IS IN GOOD AGREEMENT THAT IT WILL
OCCUR SOMETIME IN THE NEXT 24 TO 36 HOURS. GIVEN THE UNCERTAINTY...
OUR FORECAST DEPICTS A SOMEWHAT MORE GENTLE TURN THAN WHAT WILL
LIKELY HAPPEN...WHICH COULD BE A RATHER ABRUPT SWITCH IN DIRECTION
INSTEAD. WE REMAIN ON THE NORTH SIDE OF THE GUIDANCE ENVELOPE
THROUGH 48 HOURS...AND RELATIVELY CLOSE TO THE GFS SOLUTION...WITH
THE IDEA THAT NIALA WILL SHOW THE SAME RESISTANCE TO SHEAR THAT
SEVERAL OTHER CENTRAL PACIFIC CYCLONES IN OUR VICINITY HAVE SHOWN
THIS YEAR.

THE WINDOW APPEARS TO BE JUST ABOUT CLOSED NOW FOR ADDITIONAL
STRENGTHENING...AND THUS HAVE ADJUSTED THE INTENSITY FORECAST TO
KEEP NIALA STEADY-STATE THROUGH 36 HOURS...FOLLOWED BY A WEAKENING
TREND. THIS SHOULD OCCUR DESPITE THE CYCLONE STARTING TO MOVE OVER
WARMER SEA SURFACE TEMPERATURES BY THAT TIME. THE INTENSITY FORECAST
INDICATES SLOWER WEAKENING THAN MOST OF THE GUIDANCE...AND CLOSEST
TO THE ECMWF. NEVERTHELESS...NIALA IS STILL EXPECTED TO BE A REMNANT
LOW IN ABOUT 4 DAYS.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0900Z 16.8N 151.2W 45 KT 50 MPH
12H 26/1800Z 17.5N 151.9W 45 KT 50 MPH
24H 27/0600Z 17.7N 152.9W 45 KT 50 MPH
36H 27/1800Z 17.6N 154.0W 45 KT 50 MPH
48H 28/0600Z 17.3N 155.1W 40 KT 45 MPH
72H 29/0600Z 16.9N 156.4W 30 KT 35 MPH
96H 30/0600Z 16.4N 157.6W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 01/0600Z 15.6N 159.6W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
FORECASTER R BALLARD
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#67 Postby Kingarabian » Sat Sep 26, 2015 4:48 am

THE CENTRAL CORE REMAINS LARGELY INTACT FOR THE TIME
BEING WITH DEEP CONVECTION STILL WRAPPING AROUND THE SUSPECTED LOW
LEVEL CENTER. THE SATELLITE INTENSITY ESTIMATES WERE A UNANIMOUS 3.0
AND SO THE ADVISORY INTENSITY IS BEING KEPT AT 45 KT.


Yet there continues to be an evident eye on microwave:

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#68 Postby Extratropical94 » Sat Sep 26, 2015 8:10 am

Only a minor increase in wind speeds unfortunately.

CP, 06, 2015092612, , BEST, 0, 171N, 1515W, 50, 997, TS
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#69 Postby Yellow Evan » Sat Sep 26, 2015 9:48 am

This is getting ridiculous. Stop Dvoraking hugging CPHC! If they is an eye on microwave, chances are it's near hurricane intensity. Latest CIRA AMSU estimate is 64 knots and ADT is also 65 knots. SAB is T3.5 So is the Data T number from CPHC. Based on this, I'd go with 60 knots.
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#70 Postby Yellow Evan » Sat Sep 26, 2015 10:49 am

WTPA41 PHFO 261507 CCA
TCDCP1

TROPICAL STORM NIALA DISCUSSION NUMBER 7...CORRECTED
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP062015
500 AM HST SAT SEP 26 2015

LIKE MANY OF THE TROPICAL CYCLONES IN THE CENTRAL PACIFIC BASIN
THIS SEASON...NIALA IS DOING A PRETTY GOOD JOB OF SHRUGGING OFF 25
TO 35 KNOTS OF DEEP LAYER SHEAR FOR NOW. AN AMSU PASS AT 1245 UTC
AND AN SSMI PASS AT 1307 UTC STILL INDICATED A PARTIAL EYEWALL
FEATURE...BUT THERE ARE INDICATIONS THAT THE CENTER IS BECOMING
INCREASINGLY VERTICALLY TILTED OVER TIME. CONVENTIONAL SATELLITE
IMAGERY HAS SHOWN PERSISTENT VIGOROUS CONVECTION REMAINING NEAR THE
CENTER OVER THE PAST SEVERAL HOURS. SUBJECTIVE SATELLITE INTENSITY
ESTIMATES WERE A STEADY 3.0 FROM PHFO AND JTWC...WITH 3.5 FROM SAB.
THE ADT NUMBERS WERE 3.9 FROM CIMSS AND 3.4 FROM SAB. BASED ON A
CONSENSUS OF THESE DATA...HAVE RAISED THE ADVISORY INTENSITY TO 50
KT...AND THIS MAY BE A BIT CONSERVATIVE.

THE INITIAL MOTION ESTIMATE IS 315/6. NIALA IS STILL GAINING
LATITUDE AS IT FEELS THE INFLUENCE OF A LARGE MID-TO-UPPER LEVEL
TROUGH EXTENDING FAR TO THE NORTHEAST OF HAWAII. THERE IS ALSO SOME
WESTWARD COMPONENT TO THE MOTION OWING TO STRONG HIGH PRESSURE
ROUGHLY 1500 MILES NORTH OF HAWAII. THE FARTHER NORTH THAT NIALA
GETS...THE STRONGER THE SHEAR WILL BECOME...AND SOONER OR LATER THE
DEEP CONVECTION WILL COMPLETELY SEPERATE FROM THE LOW LEVEL
CIRCULATION CENTER. THIS WILL CAUSE NIALA TO RATHER ABRUPTLY BECOME
STEERED TOWARD THE WEST-SOUTHWEST BY THE LOW LEVEL FLOW. IT IS
DIFFICULT TO SAY EXACTLY WHEN THIS WILL HAPPEN...LEADING TO A FAIR
AMOUNT OF UNCERTAINTY IN THE FORECAST AND THE PRIMARY REASON FOR
MAINTAINING THE TROPICAL STORM WATCH FOR THE BIG ISLAND. OUR
FORECAST DEPICTS A MORE GENTLE TURN OVER THE NEXT 36-48 HOURS THAN
DEPICTED BY MOST OF THE GUIDANCE WHICH IS LIKELY TOO QUICK TO
DECOUPLE NIALA. AFTER 48 HOURS...THE FORECAST TRACK MORE CLOSELY
FALLS IN LINE WITH THE CONSENSUS TRACKS. IT SHOULD BE NOTED THERE IS
CONSIDERABLE SPREAD IN THE GUIDANCE REGARDING THE SPEED OF THE
SYSTEM IN THE 72-120 HOUR TIME FRAME.

IT SEEMS UNLIKELY THAT NIALA WOULD STRENGTHEN MUCH MORE GIVEN THE
INCREASINGLY HOSTILE CONDITIONS THE CYCLONE WILL ENCOUNTER. HAVE
INDICATED A GRADUAL WEAKENING THROUGH THE FIRST 48 HOURS...WITH MORE
RAPID WEAKENING TO REMNANT LOW BY 96 HOURS IN THE FACE OF RELENTLESS
SHEAR. THIS WEAKENING TREND IS A LITTLE SLOWER WHAT MOST OF THE
GUIDANCE INDICATES...AND IS MORE IN LINE WITH THE ECMWF FOR THE
FIRST 48 HOURS...THEN WEAKENS MORE QUICKLY IN THE DAYS 3-5
TIMEFRAME.


FORECAST POSITIONS AND MAX WINDS

INIT 26/1500Z 17.3N 151.7W 50 KT 60 MPH
12H 27/0000Z 17.7N 152.5W 45 KT 50 MPH
24H 27/1200Z 17.8N 153.5W 45 KT 50 MPH
36H 28/0000Z 17.6N 154.6W 45 KT 50 MPH
48H 28/1200Z 17.3N 155.6W 40 KT 45 MPH
72H 29/1200Z 16.6N 157.4W 30 KT 35 MPH
96H 30/1200Z 15.9N 159.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 01/1200Z 15.2N 161.5W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
FORECASTER R BALLARD
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#71 Postby Kingarabian » Sat Sep 26, 2015 11:07 am

I guess the CPHC has different definitions on what is a hurricane and what is not.

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AMSR2 SSMIS and AMSU all show an eye on microwave. Microwave imagery is as sure as it gets when it comes to reliability, coming in 3rd after Recon and ASCAT.
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#72 Postby Alyono » Sat Sep 26, 2015 12:21 pm

its not a cane. CPHC is correct on that. I also have this at 50 kts
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Re:

#73 Postby Yellow Evan » Sat Sep 26, 2015 12:25 pm

Alyono wrote:its not a cane. CPHC is correct on that. I also have this at 50 kts


Would you expect a 50 knot TS to have a ragged eye on microwave?

It's not a cane now, but it likely peaked at around 60 knts and is around 55-60 knots now.
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Re: Re:

#74 Postby Alyono » Sat Sep 26, 2015 12:30 pm

Yellow Evan wrote:
Alyono wrote:its not a cane. CPHC is correct on that. I also have this at 50 kts


Would you expect a 50 knot TS to have a ragged eye on microwave?

It's not a cane now, but it likely peaked at around 60 knts and is around 55-60 knots now.


yes, I've seen eyes on microwave and from recon for 50 kt tropical storms
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Re: Re:

#75 Postby Yellow Evan » Sat Sep 26, 2015 12:49 pm

Alyono wrote:
Yellow Evan wrote:
Alyono wrote:its not a cane. CPHC is correct on that. I also have this at 50 kts


Would you expect a 50 knot TS to have a ragged eye on microwave?

It's not a cane now, but it likely peaked at around 60 knts and is around 55-60 knots now.


yes, I've seen eyes on microwave and from recon for 50 kt tropical storms


I have too, but there are plenty of storms that don't. Allison 95 didn't have any microwave eye IIRC and it was a hurricane.
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#76 Postby Kingarabian » Sat Sep 26, 2015 2:26 pm

Well. Looks like it's weakening now.
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#77 Postby Yellow Evan » Sat Sep 26, 2015 2:31 pm

CPHC begs to differ

Code: Select all

CP, 06, 2015092618,   , BEST,   0, 171N, 1518W,  55,  992, TS,  34, NEQ,   80,   70,   30,   50, 1009,  160,  20,   0,   0,   C,   0,    ,   0,   0,      NIALA, D,


This was 55 knts at 6-12z. Not now.
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Re: CPAC: NIALA - Tropical Storm

#78 Postby supercane » Sat Sep 26, 2015 4:02 pm

WTPA41 PHFO 262050
TCDCP1

TROPICAL STORM NIALA DISCUSSION NUMBER 8
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP062015
1100 AM HST SAT SEP 26 2015

SSMIS PASSES AT 1640 UTC AND 1714 UTC...COMBINED WITH A SHORT
VISIBLE SATELLITE LOOP...CONFIRM THAT NIALA HAS MADE ITS EXPECTED
TURN TOWARD THE WEST...AND MAY HAVE BEGUN TO MAKE THIS TURN BEFORE
THE 1200 UTC SATELLITE ANALYSIS CYCLE. WHAT APPEARS TO BE THE
WESTERN EDGE OF THE LOW LEVEL CIRCULATION CENTER..LLCC...IS PEEKING
OUT FROM UNDER DEEP CONVECTION. WINDS AT NEARBY BUOY ONE HAVE BEGUN
TO BACK...POSSIBLY INDICATING THAT NIALA IS ON TRACK TO PASS SOUTH
OF IT. OVERALL SATELLITE PRESENTATION IS OF A SYSTEM UNDERGOING
HIGH AMOUNTS OF WEST SOUTHWESTERLY SHEAR...VARYING FROM 25
KT...ACCORDING TO SHIPS...TO 35 KT...ACCORDING TO UW-CIMSS. THE
SOLE OUTFLOW CHANNEL IS TO THE NORTHEAST. SUBJECTIVE SATELLITE
INTENSITY ESTIMATES RANGE FROM 3.5...55 KT...FROM PHFO AND SAB...TO
3.0...45 KT...FROM JTWC. UW-CIMSS ADT REPRESENTS THE HIGH END AT
4.0...65 KT. REANALYSIS OF SATELLITE AND MICROWAVE DATA SHOWS THAT
NIALA WAS LIKELY STRONGER THAN ASSIGNED 24 HOURS AGO...POSSIBLY
FLIRTING WITH HURRICANE STRENGTH THEN. OUR 55 KT INITIAL INTENSITY
FOR THIS FORECAST CYCLE REPRESENTS A WEAKENING FROM THAT PEAK
INTENSITY 24 HOURS AGO...AND IS NOT MEANT TO REPRESENT STRENGTHENING
OVER THE PAST 6 TO 12 HOURS. NIALA IS ON A WEAKENING TREND AND HAS
BEEN SINCE LATE FRIDAY.

INITIAL MOTION IS 270/06 KT...ALTHOUGH 12 HOUR MOTION STILL SHOWS A
CONSIDERABLE...AND NOW POSSIBLY UNREPRESENTATIVE...NORTHERLY
COMPONENT. A STRONG HIGH PRESSURE CENTER FAR NORTH OF HAWAII APPEARS
TO BE GAINING INFLUENCE OVER NIALA AT THE EXPENSE OF MID AND UPPER
TROUGHING EXTENDING FAR TO THE NORTHEAST OF HAWAII. THIS IS TO BE
EXPECTED AS DEEP CONVECTION IS INCREASINGLY SHEARED AWAY. TO ACCOUNT
FOR INITIAL MOTION...THE 12...24 AND 36 HOUR FORECAST POINTS WERE
ADJUSTED NOTICEABLY TO THE LEFT OF THE PREVIOUS FORECAST...WITH THE
REST OF THE TRACK CLOSELY ALIGNING WITH THE PREVIOUS ONE. THIS KEEPS
THE FINAL FORECAST TRACK WITHIN THE TIGHT CONSENSUS TRACK GUIDANCE
ENVELOPE...AND TAKES NIALA 120 TO 150 MILES SOUTH OF THE BIG ISLAND
BETWEEN 24 AND 48 HOURS. THE SHORT-TERM FORECAST TRACK SHIFT TO THE
LEFT NEGATED ANY EFFECT THE HIGHER INITIAL INTENSITY HAD ON 34 KT
WIND PROBABILITIES...SO THE TROPICAL STORM WATCH FOR THE BIG ISLAND
WILL CONTINUE UNCHANGED. IT IS VERY LATE IN THE FORECAST CYCLE
NOW...AND 2000 UTC GOES VISIBLE IMAGERY SHOWS OUR ALTERED INITIAL
POSITION MAY STILL BE A TENTH OF A DEGREE TOO FAR NORTH.

AGAIN...TROPICAL STORM NIALA LIKELY PEAKED NEAR HURRICANE STRENGTH
ABOUT 24 HOURS AGO AND HAS BEEN WEAKENING EVER SINCE. THIS TREND
WILL CONTINUE THROUGH THE NEXT FIVE DAYS IN THE FACE OF INCREASING
SHEAR...IN SPITE OF CONTINUED WARM SSTS. MOST INTENSITY GUIDANCE
WEAKENS NIALA VERY QUICKLY...WITH SHIPS ESSENTIALLY DISSIPATING THIS
SYSTEM BY 120 HOURS. THIS SEASON HAS HAD ITS SHARE OF RESILIENT
TROPICAL SYSTEMS...SO OUR FORECAST WEAKENING TREND IS NOT AS QUICK
AS MOST GUIDANCE. AFTER SLOWLY WEAKENING THROUGH 48 HOURS...WE
FORECAST NIALA WILL DEGRADE TO A POST-TROPICAL REMNANT LOW...BUT NOT
DISSIPATE...ON DAY FOUR.


FORECAST POSITIONS AND MAX WINDS

INIT 26/2100Z 17.1N 152.1W 55 KT 65 MPH
12H 27/0600Z 17.1N 152.8W 50 KT 60 MPH
24H 27/1800Z 17.1N 153.8W 45 KT 50 MPH
36H 28/0600Z 16.9N 154.9W 45 KT 50 MPH
48H 28/1800Z 16.7N 155.9W 40 KT 45 MPH
72H 29/1800Z 16.1N 157.7W 30 KT 35 MPH
96H 30/1800Z 15.5N 159.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 01/1800Z 14.8N 161.8W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
FORECASTER POWELL
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#79 Postby Kingarabian » Sat Sep 26, 2015 4:08 pm

Of course it was likely stronger than assigned 24 hours ago. Making it strong now does not justify not upgrading it to hurricane status when it was a hurricane despite having the chance to do so twice. Hopefully they upgrade in post season analysis.
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#80 Postby TropicalAnalystwx13 » Sat Sep 26, 2015 4:09 pm

At least the Central Pacific Hurricane Center acknowledges their mistake. The peak intensity will be raised to either 60kt or 65kt in post-season analysis.
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