Hurricane Ioke thread

[bob rulz]

I'm pretty sure that Johnston Island is uninhabited now.

I'm 95% sure it is. I never really saw any reason for them to issue a hurricane warning, but hey, if it gives us forecasts every 3 hours instead of 6, I'm all for it.

[chadtm80]

You are correct. Uninhabitated
But your right bob.. Just means more Forecasts

[wxmann_91]

Eye popping out... outflow enhancement has cancelled out shear effects.

[JonathanBelles]

erc?

[wxmann_91]

That too fact.

[JonathanBelles]

then could it restrengthen?

[WindRunner]

Also, anybody got the SHIPS intensity forecast? Drastically different shear values than previous runs.

In terms of what? Intensity? Not really, still a rapid weakening from the T+0 intensity. The shear, however, is up in the later period, and even thoguh we all know that SHIPS tends to overestimate shear, an increase is still an increase. (unless the overestimation factor isn't linear, but let's not get into that )


And it is nice to see that eye poking back out . . .

[CrazyC83]

I think it just went through an eyewall cycle.

[wxmann_91]

The trend is Ioke's friend.

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 90 82 75 71 70 69 70 71 71 69 66 65 64
V (KT) LAND 90 82 75 71 70 69 70 71 71 69 66 65 64
V (KT) LGE mod 90 82 77 74 72 70 71 73 76 78 77 75 DIS

SHEAR (KTS) 10 9 11 8 6 6 1 1 7 13 14 21 N/A
SHEAR DIR 290 302 307 330 327 349 156 223 281 309 320 318 9999
SST (C) 27.7 27.7 27.7 27.7 27.7 27.7 27.8 27.9 27.9 28.0 28.0 28.1 N/A
POT. INT. (KT) 140 140 140 140 140 140 140 141 141 142 142 143 N/A
200 MB T (C) -52.7 -52.5 -52.6 -52.9 -52.8 -52.9 -52.7 -52.7 -52.5 -52.9 -52.9 -53.4 N/A
TH_E DEV (C) 10 10 10 10 10 10 10 10 9 10 9 9 N/A
500-300 MB RH 40 36 32 33 35 31 34 37 43 45 54 60 N/A
850 MB VORT 0 -2 -7 -11 1 -23 -18 -20 -31 -19 -18 -5 N/A
200 MB DIV 20 -7 -9 -1 26 25 -7 9 21 29 38 35 N/A
LAND (KM) 1234 1254 1278 1308 1341 1423 1517 1619 1704 1796 1889 1993 N/A
LAT (DEG N) 16.3 16.9 17.4 17.8 18.2 19.0 19.7 20.2 20.6 20.7 20.7 20.6 N/A
LONG(DEG W) 169.9 170.5 171.0 171.5 172.0 173.1 174.2 175.3 176.2 177.1 178.0 179.0 N/A
STM SPEED (KT) 8 8 7 6 7 7 6 5 4 4 4 5 N/A
FORECAST TRACK FROM OFCI

Compare: http://www.storm2k.org/phpbb2/viewtopic ... 50#1427550

The GFDL initialized the lowest it had for several runs, yet the result at 120 hr is still the same:

[WindRunner]

Just to keep the archive up-to-date.

WTPA42 PHFO 230245
TCDCP2

HURRICANE IOKE DISCUSSION NUMBER 13
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP012006
500 PM HST TUE AUG 22 2006

SUBJECTIVE DVORAK INTENSITY ESTIMATES INDICATE LITTLE CHANGE IN THE INTENSITY OF IOKE IN THE PAST 6 HOURS. THE EYE...WHICH HAD DISAPPEARED FOR A WHILE...HAS REMAINED DIMLY VISIBLE FOR THE PAST FEW HOURS. AT 02Z...THE NORTHEAST PART OF THE EYEWALL WAS OVER JOHNSTON ISLAND. THE 00Z CIMSS VERTICAL SHEAR PRODUCT SHOWS A SLIGHT DECREASE TO 6M/S SHEAR FROM 241 DEGREES SO WE WILL BE KEEPING THE INITIAL INTENSITY AT T5.0 OR 90 KT.

IOKE CONTINUES TO MOVE NORTHWESTWARD BUT THE FORWARD MOTION HAS SLOWED OVER THE PAST 6 HOURS. MODEL GUIDANCE IS EVEN MORE TIGHTLY CLUSTERED THAN 6 HOURS AGO...SHOWING A CONTINUED NORTHWEST MOVEMENT THROUGH 72 HOURS...THEN SLOWING AND CURVING TOWARDS SLIGHTLY SOUTH OF WEST. WE HAVE MADE NO CHANGES TO THE TRACK THROUGH 48 HOURS... THEN SHIFTED THE FORECAST TRACK FARTHER SOUTH AND SLOWED THE FORWARD MOTION TO STICK CLOSER TO THE MODEL CONSENSUS.

THE FORECAST TRACK TAKES IOKE OVER 28 DEGREE C WATER THROUGH 120 HOURS. THE MODEST SOUTHWEST SHEAR IS FORECAST TO DECREASE SLIGHTLY AND REMAIN LOW THROUGH 72 HOURS. WE HAVE KEPT THE INTENSITY UNCHANGED THROUGH 96 HOURS...THEN STARTED A GRADUAL WEAKENING AS SHEAR INCREASES FROM THE NORTHWEST.

FORECAST POSITIONS AND MAX WINDS

INITIAL 23/0300Z 16.6N 170.2W 90 KT
12HR VT 23/1200Z 17.4N 171.0W 90 KT
24HR VT 24/0000Z 18.3N 172.1W 90 KT
36HR VT 24/1200Z 19.0N 173.2W 90 KT
48HR VT 25/0000Z 19.7N 174.2W 90 KT
72HR VT 26/0000Z 20.5N 176.0W 90 KT
96HR VT 27/0000Z 20.6N 177.3W 90 KT
120HR VT 28/0000Z 20.4N 178.5W 85 KT


$$
FORECASTER DONALDSON

[WindRunner]

Now forecast to become a typhoon with a good WSW component coming in around 72hrs . . . i.e. good chance of continuing south and being able to restrengthen in the WPAC.

WTPA42 PHFO 230904
TCDCP2

HURRICANE IOKE DISCUSSION NUMBER 14
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP012006
1100 PM HST TUE AUG 22 2006

INTENSITY ESTIMATES FROM THE VARIOUS AGENCIES INDICATE THAT IOKE HAS MAINTAINED STRENGTH OVER THE PAST SIX HOURS. ALTHOUGH THE EYE HAS BECOME LESS DEFINED IN SATELLITE IMAGERY ONCE AGAIN...THERE WAS A RENEWED BURST OF DEEP CONVECTION AROUND THE CENTER AS THE HURRICANE MADE ITS CLOSEST APPROACH TO JOHNSTON ISLAND EARLIER THIS EVENING. THE 0507Z SSMI PASS SHOWED THAT JOHNSTON ISLAND WAS SQUARELY IN THE EASTERN EYEWALL OF IOKE.

THE INITIAL MOTION IS 315/8. IOKE IS CURRENTLY HEADING NORTHWEST TOWARD A WEAKNESS IN THE SUBTROPICAL RIDGE AND AN EXTRATROPICAL LOW NEAR 28N 178E. MODEL GUIDANCE REMAINS IN EXCELLENT AGREEMENT THAT THE EXTRATROPICAL LOW WILL RETROGRADE WESTWARD AND WEAK LOW LEVEL RIDGING TO THE NORTH WILL ALLOW IOKE TO CONTINUE ON A NORTHWEST TRACK THROUGH THE NEXT 72 HOURS. THEREAFTER...STRONGER RIDGING TO THE NORTH AND NORTHWEST OF IOKE IS EXPECTED TO TURN THE HURRICANE ON A WEST-SOUTHWESTERLY COURSE.

SATELLITE DERIVED HIGH LEVEL WIND ANALYSES INDICATE THAT IOKE IS SKIRTING THE WESTERN PERIPHERY OF AN UPPER LEVEL JET STREAK TO THE NORTHEAST OF THE CYCLONE. THERE IS STRONG SHEAR JUST TO THE NORTHEAST OF IOKE...BUT THE CORE OF THE HURRICANE REMAINS UNDER RELATIVELY WEAK SHEAR. MODEL GUIDANCE SUGGESTS THAT STRENGTHENING UPPER LEVEL RIDGING OVER IOKE WILL ACTUALLY REDUCE SHEAR THROUGH THE NEXT 72 HOURS. IN THE LONGER TERM...IOKE WILL LIKELY BEGIN TO FEEL THE INFLUENCE OF A RATHER STRONG DIGGING TROUGH BETWEEN 160W AND 170W...WITH INCREASING NORTHERLY SHEAR INDUCING SHEARING.

FORECAST POSITIONS AND MAX WINDS

INITIAL 23/0900Z 17.2N 170.5W 90 KT
12HR VT 23/1800Z 17.9N 171.3W 90 KT
24HR VT 24/0600Z 18.7N 172.4W 90 KT
36HR VT 24/1800Z 19.4N 173.4W 90 KT
48HR VT 25/0600Z 20.2N 174.7W 90 KT
72HR VT 26/0600Z 20.9N 176.9W 90 KT
96HR VT 27/0600Z 20.3N 179.0W 85 KT
120HR VT 28/0600Z 19.5N 179.3E 80 KT


$$
FORECASTER R BALLARD/HOUSTON

[HURAKAN]

23/0600 UTC 16.9N 170.3W T5.5/5.5 IOKE -- Central Pacific Ocean

Fighting back!!!

[senorpepr]

Sort of off-topic here, but I keep hearing OCMs pronounce Ioke as ee-OH-kee instead of ee-OH-keh (like ee-Okay). In Hawaiian, the letter e is a soft sound--not a hard EE sound.

[WindRunner]

WTPA42 PHFO 231503
TCDCP2

HURRICANE IOKE DISCUSSION NUMBER 15
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP012006
500 AM HST WED AUG 23 2006

ALTHOUGH THERE HAS BEEN AN INTERMITTENT RAGGED EYE FEATURE APPARENT IN THE INFRARED IMAGERY OVER THE PAST FEW HOURS...FOR THE MOST PART THE EYE REMAINS CLOUD-FILLED. SUBJECTIVE DVORAK INTENSITY ESTIMATES HAVE REMAINED CONSTANT FROM ALL THE AGENCIES OVER THE PAST 12 HOURS...AND WE WILL MAINTAIN A CURRENT INTENSITY OF 90 KT.

THE INITIAL MOTION IS 320/6. THERE IS LITTLE CHANGE TO THE FORECAST PHILOSOPHY. MODEL GUIDANCE REMAINS TIGHTLY CLUSTERED...ESPECIALLY IN THE NEAR TERM. THROUGH THE NEXT 36 TO 48 HOURS...IOKE WILL CONTINUE TO BE DRAWN SLOWLY NORTHWESTWARD ALONG THE PERIPHERY OF THE SUBTROPICAL RIDGE AND TOWARD A NEARLY STATIONARY EXTRATROPICAL LOW JUST WEST OF THE DATELINE NEAR 28N. AFTERWARD...THE EXTRATROPICAL LOW IS EXPECTED TO LIFT BACK INTO THE NORTH PACIFIC WESTERLIES...AND STRONG DEEP LAYER RIDGING BUILDS TO THE NORTH AND WEST OF IOKE WHICH WILL FORCE THE CYCLONE BACK TOWARD THE WEST- SOUTHWEST.

THE MODEST WESTERLY SHEAR APPEARS TO BE RELAXING AS SATELLITE IMAGERY INDICATES IMPROVING OUTFLOW OVER IOKE. MODELS AGREE THAT THE SHEAR WILL CONTINUE TO RELAX THROUGH 36 HOURS AS IOKE MOVES UNDERNEATH AN UPPER LEVEL RIDGE AXIS. THE SSTS ARE WARM AND SO CONDITIONS APPEAR TO BE FAVORABLE FOR MODEST STRENGTHENING. IN THE LONGER TERM...THE UPPER RIDGE AXIS WILL SHIFT MORE QUICKLY WESTWARD AND IOKE WILL LIKELY BEGIN TO FEEL THE INFLUENCE OF A RATHER STRONG DIGGING TROUGH BETWEEN ABOUT 160W AND 170W...WITH INCREASING NORTHERLY SHEAR INDUCING WEAKENING.

FORECAST POSITIONS AND MAX WINDS

INITIAL 23/1500Z 17.6N 170.7W 90 KT
12HR VT 24/0000Z 18.3N 171.5W 90 KT
24HR VT 24/1200Z 19.0N 172.7W 95 KT
36HR VT 25/0000Z 19.7N 173.9W 95 KT
48HR VT 25/1200Z 20.3N 175.0W 90 KT
72HR VT 26/1200Z 20.5N 177.6W 85 KT
96HR VT 27/1200Z 19.5N 179.8W 75 KT
120HR VT 28/1200Z 18.5N 178.3E 65 KT


$$
FORECASTER R BALLARD/HOUSTON



Restrengthening forecast as outflow improves. Almost SWly component to the motion by the end of the track.

[wxmann_91]

GFDL goes bonkers intensifying this to a high-end Cat 4 while making Ioke nearly go south, down to 15 degrees N. Good entertainment. Meanwhile the SHIPS induce 36 kt of shear over Ioke at the same time. Hmmmm...

[clfenwi]

Somehow an Air Force (?!) research vessel got caught in the area and the crew took refuge in a bunker on Johnston Island:

http://starbulletin.com/2006/08/23/news/story01.html

[CrazyC83]

GFDL goes bonkers intensifying this to a high-end Cat 4 while making Ioke nearly go south, down to 15 degrees N. Good entertainment. Meanwhile the SHIPS induce 36 kt of shear over Ioke at the same time. Hmmmm...

Knowing how GFDL has done the last couple years, I wouldn't be surprised to see such happen.

[Matt-hurricanewatcher]

It would be something if this turned southeastward in then turned back to the northeast to the islands.

[WindRunner]

GFDL goes bonkers intensifying this to a high-end Cat 4 while making Ioke nearly go south, down to 15 degrees N. Good entertainment. Meanwhile the SHIPS induce 36 kt of shear over Ioke at the same time. Hmmmm...

I believe either someone here or the CPHC said that the GFDL has been nailing Ioke so far . . . of course, that was before this "weakening" . . . granted it did weaken, by I don't quite think 90kts is still accurate for Ioke. The GFDL might be a touch high, but it's all about the trends - i.e. south and strong . . .

[Cyclenall]

I believe either someone here or the CPHC said that the GFDL has been nailing Ioke so far . . . of course, that was before this "weakening" . . . granted it did weaken, by I don't quite think 90kts is still accurate for Ioke. The GFDL might be a touch high, but it's all about the trends - i.e. south and strong . . .

The GFDL has nailed this system so far in many ways. It was really impressive so don't doubt the GFDL on this system since it's been excellent in forecasting Ioke.