EPAC: Disturbance Iselle

[Chacor]

TD 10E prediction challenge.

Reminder that this is still open for 9 more hours.

[HURAKAN]

TROPICAL STORM ISELLE DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
200 AM PDT THU AUG 14 2008

THE CONVECTIVE PATTERN HAS BECOME SLIGHTLY MORE SYMMETRIC...BUT
MICROWAVE IMAGERY INDICATES THE LOW-LEVEL CENTER IS STILL BENEATH
THE NORTHEASTERN PORTION OF THE DEEP CONVECTION. THE DVORAK
INTENSITY ESTIMATES ARE UNCHANGED FROM THE PREVIOUS CYCLE AT 35-45
KT...BUT MANUAL ANALYSIS OF THE AMBIGUITIES FROM A QUIKSCAT PASS AT
AROUND 01Z SUGGESTS MAXIMUM WINDS OF ABOUT 40 KT...SO THE ADVISORY
INTENSITY IS NUDGED UPWARD TO 40 KT. THE CYCLONE IS STRUGGLING IN
THE FACE OF EASTERLY SHEAR...AND DYNAMICAL MODELS FORECAST THE
SHEAR TO PERSIST THROUGHOUT THE FIVE-DAY FORECAST PERIOD...WITH
PERHAPS EVEN A SLIGHT INCREASE IN SHEAR IN THE SHORT TERM. AS A
RESULT...DESPITE WARM WATERS ALONG THE FORECAST TRACK FOR THE NEXT
TWO TO THREE DAYS...NONE OF THE OBJECTIVE INTENSITY MODELS FORECAST
MUCH STRENGTHENING IF AT ALL. THE OFFICIAL FORECAST CLOSELY
FOLLOWS THE SHIPS AND LGEM GUIDANCE IN CALLING FOR VERY LITTLE
CHANGE IN STRENGTH THROUGH ABOUT 72 HOURS...FOLLOWED BY WEAKENING
OVER COOLER WATERS. GIVEN THE PERSISTENT SHEAR...AND THE
LESS-THAN-IMPRESSIVE DEPICTIONS OF THE CYCLONE IN THE DYNAMICAL
MODEL FIELDS...IT REMAINS POSSIBLE THAT ISELLE WILL NOT LAST THE
ENTIRE FIVE-DAY PERIOD.

THE 01Z QUIKSCAT PASS...AND PASSIVE MICROWAVE IMAGERY FROM SSMIS AND
TRMM AT AROUND THAT SAME TIME...INDICATE THAT THE CENTER OF ISELLE
IS MOVING A TINY BIT SOUTH OF THE PREVIOUS TRACK...AND THE INITIAL
MOTION ESTIMATE IS ABOUT 290/9. ISELLE IS BEING STEERED BY A MID-
TO UPPER-LEVEL RIDGE OVER NORTHERN MEXICO...AND ALL OF THE
DYNAMICAL MODELS FORECAST THE CYCLONE TO CONTINUE MOVING GENERALLY
WEST-NORTHWESTWARD OR NORTHWESTWARD FOR THE NEXT TWO TO THREE DAYS
ALONG THE SOUTHWESTERN PERIPHERY OF THAT RIDGE. THE SPREAD IN THE
TRACK GUIDANCE IS SIGNIFICANT THROUGH 72 HOURS AND BECOMES
PARTICULARLY LARGE BEYOND THAT TIME...SEEMINGLY IN PART BECAUSE THE
MODELS DO NOT AGREE ON THE STRENGTH AND DEPTH OF ISELLE. SOME
MODELS INCLUDING THE GFS AND UKMET FORECAST THE CYCLONE TO HAVE
DISSIPATED BY DAY 3. PRESUMING A WEAKENED ISELLE DOES LAST INTO
THE 3-5 DAY TIME FRAME...IT WILL PROBABLY NOT BE MOVING VERY FAST
SINCE IT WILL LIKELY BE TOO FAR EAST TO GET CAUGHT UP IN THE
LOW-LEVEL EASTERLY TRADES. THE NEW OFFICIAL TRACK FORECAST IS VERY
SIMILAR TO THE PREVIOUS ONE...AND IS CLOSE TO THE CONSENSUS THROUGH
ABOUT 48 HOURS.



FORECAST POSITIONS AND MAX WINDS

INITIAL 14/0900Z 17.6N 108.6W 40 KT
12HR VT 14/1800Z 18.3N 109.8W 45 KT
24HR VT 15/0600Z 19.1N 110.9W 45 KT
36HR VT 15/1800Z 19.9N 112.0W 45 KT
48HR VT 16/0600Z 20.5N 113.1W 45 KT
72HR VT 17/0600Z 21.0N 114.5W 40 KT
96HR VT 18/0600Z 21.5N 116.0W 30 KT
120HR VT 19/0600Z 21.5N 117.5W 25 KT

$$
FORECASTER KNABB

[HURAKAN]

EP, 10, 2008081412, , BEST, 0, 177N, 1091W, 45, 999, TS,

[HURAKAN]

458
WTPZ35 KNHC 141436
TCPEP5
BULLETIN
TROPICAL STORM ISELLE ADVISORY NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 AM PDT THU AUG 14 2008

AT 800 AM PDT...1500 UTC...THE CENTER OF TROPICAL STORM ISELLE WAS
LOCATED NEAR LATITUDE 17.8 NORTH...LONGITUDE 109.4 WEST OR ABOUT 355
MILES...570 KM...SOUTH OF THE SOUTHERN TIP OF BAJA CALIFORNIA.

ISELLE IS MOVING TOWARD THE NORTHWEST NEAR 8 MPH...13 KM/HR...AND
THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS
WITH A GRADUAL TURN TOWARD THE WEST-NORTHWEST POSSIBLE IN SATURDAY.
ON THIS TRACK...ISELLE WILL REMAIN WELL OFFSHORE FROM THE PACIFIC
COAST OF MEXICO AND BAJA CALIFORNIA THROUGH FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/HR...WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 24
HOURS...WITH GRADUAL WEAKENING EXPECTED THEREAFTER.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

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

REPEATING THE 800 AM PDT POSITION...17.8 N...109.4 W. MOVEMENT
TOWARD...NORTHWEST NEAR 8 MPH. MAXIMUM SUSTAINED WINDS...50 MPH.
MINIMUM CENTRAL PRESSURE...999 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
200 PM PDT.

$$
FORECASTER STEWART/BEVEN

[HURAKAN]

556
WTPZ45 KNHC 141433
TCDEP5
TROPICAL STORM ISELLE DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 AM PDT THU AUG 14 2008

ANOTHER IMPRESSIVE NOCTURNAL BURST OF CONVECTION DEVELOPED
WELL-DEFINED MID- AND LOW-LEVEL CIRCULATION CENTERS AS NOTED IN A
14/0921Z TRMM OVERPASS. HOWEVER...SINCE THAT TIME...THE OVERALL
CONVECTIVE PATTERN HAS DETERIORATED SOMEWHAT DUE TO INCREASING
NORTHEASTERLY SHEAR. THE INITIAL INTENSITY WAS INCREASED TO 45 KT
AT 12Z AND FOR THE ADVISORY TIME BASED ON CONSENSUS T3.0 SATELLITE
ESTIMATES FROM TAFB AND SAB. THIS MAY BE A LITTLE GENEROUS AT THIS
TIME...BUT ISELLE HAS HAD A HISTORY OF REDEVELOPING DEEP CONVECTION
IN THE FACE OF OTHERWISE HOSTILE CONDITIONS. THE CENTER LOCATION IS
BASED ON EXTRAPOLATING THE VORTEX TILT TO THE NORTHEAST NOTED IN
TRMM IMAGERY AND USING THE STORM MOTION FROM THE PREVIOUS ADVISORY.

TROPICAL STORM ISELLE IS EXPECTED TO CONTINUE IN A GENERAL
WEST-NORTHWESTWARD MOTION THROUGH 72 HOURS...AND THEN TURN WESTWARD
AFTER THAT AS A WEAKENING TROPICAL CYCLONE OR REMNANT LOW THAT IS
STEERED BY THE LOW-LEVEL EASTERLIES NORTH OF THE SYSTEM. THE
MAJORITY OF THE NHC MODEL GUIDANCE SUPPORTS THIS SCENARIO...EXCEPT
FOR THE GFDL AND A UKMET MODELS WHICH TAKE THE CYCLONE SLOWLY
NORTH-NORTHWESTWARD. THE OFFICIAL FORECAST TRACK LEANS MORE TOWARD
A WESTWARD MOTION LATE IN THE PERIOD AS ISELLE IS EXPECTED TO COME
UNDER THE INFLUENCE OF A LARGER CYCLONIC GYRE CURRENTLY CENTERED
ABOUT 650 NMI TO ITS WEST-SOUTHWEST. THE OFFICIAL FORECAST TRACK IS
A LITTLE SOUTH OF THE PREVIOUS TRACK AND SIMILAR TO THE NHC MODEL
CONSENSUS.

VERTICAL SHEAR IS EXPECTED REMAIN BETWEEN 25 TO 30 KT THROUGH 96
HOURS. THESE UNFAVORABLE UPPER-LEVEL CONDITIONS...COUPLED WITH
DECREASING SEA-SURFACE TEMPERATURES...ARE EXPECTED TO INDUCE
GRADUAL WEAKENING BY 24-36 HOURS...OF NOT SOONER. THE OFFICIAL
INTENSITY FORECAST IS SIMILAR TO BUT SLIGHTLY LESS THAN THE SHIPS
INTENSITY MODEL.


FORECAST POSITIONS AND MAX WINDS

INITIAL 14/1500Z 17.8N 109.4W 45 KT
12HR VT 15/0000Z 18.4N 110.5W 45 KT
24HR VT 15/1200Z 19.1N 111.8W 45 KT
36HR VT 16/0000Z 19.7N 112.8W 40 KT
48HR VT 16/1200Z 20.2N 113.9W 40 KT
72HR VT 17/1200Z 20.8N 115.4W 35 KT
96HR VT 18/1200Z 21.0N 116.5W 30 KT
120HR VT 19/1200Z 21.0N 118.0W 25 KT

$$
FORECASTER STEWART/BEVEN

[HURAKAN]

[HURAKAN]

TROPICAL STORM ISELLE ADVISORY NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
200 PM PDT THU AUG 14 2008

AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL STORM ISELLE WAS
LOCATED NEAR LATITUDE 17.8 NORTH...LONGITUDE 110.2 WEST OR ABOUT 355
MILES...570 KM...SOUTH OF THE SOUTHERN TIP OF BAJA CALIFORNIA.

ISELLE IS MOVING TOWARD THE WEST-NORTHWEST NEAR 8 MPH...13 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 48
HOURS. ON THIS TRACK...ISELLE WILL REMAIN WELL OFFSHORE FROM THE
PACIFIC COAST OF MEXICO AND BAJA CALIFORNIA THROUGH FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER
GUSTS. GRADUAL WEAKENING IS FORECAST DURING THE NEXT 48 HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB...29.59 INCHES.

REPEATING THE 200 PM PDT POSITION...17.8 N...110.2 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 8 MPH. MAXIMUM SUSTAINED WINDS...45
MPH. MINIMUM CENTRAL PRESSURE...1002 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
800 PM PDT.

$$
FORECASTER STEWART

[HURAKAN]

TROPICAL STORM ISELLE DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
200 PM PDT THU AUG 14 2008

TROPICAL STORM ISELLE HAS WEAKENED AS NORTHEASTERLY VERTICAL WIND
SHEAR HAS INCREASED ACROSS THE CYCLONE. THE ADVISORY INTENSITY IS
BASED ON A CONSENSUS SATELLITE INTENSITY ESTIMATE OF 40 KT FROM
TAFB AND SAB.

TROPICAL STORM ISELLE HAS MADE A SLIGHT JOG TO THE WEST DURING THE
PAST 6 HOURS...BUT THIS MAY BE A TEMPORARY MOTION DUE TO THE
EARLIER WEAKENING OF THE INNER-CORE CONVECTION. HOWEVER...
CONVECTION IN THE SOUTHWESTERN QUADRANT HAS REDEVELOPED...SO A TURN
TO THE WEST-NORTHWEST IS EXPECTED TO RESUME AND CONTINUE FOR THE
NEXT 48 HOURS OR SO. AFTERWARD...A SHALLOW TROPICAL DEPRESSION OR
REMNANT LOW IS FORECAST TO TURN WESTWARD AS THE CIRCULATION GETS
STEERED BY THE LOW-LEVEL EASTERLIES NORTH OF THE SYSTEM...AND ALSO
POSSIBLY DUE TO INTERACTION WITH A LARGER CYCLONIC GYRE SITUATED TO
THE WEST-SOUTHWEST OF ISELLE. ALL OF THE NHC MODEL GUIDANCE NOW
SUPPORTS THIS SCENARIO AND THERE ARE NO LONGER ANY MODELS THAT TAKE
ISELLE TOWARD SOUTHERN BAJA CALIFORNIA. THE OFFICIAL FORECAST TRACK
IS SOUTH OF THE PREVIOUS TRACK AND IS SIMILAR TO THE NHC MODEL
CONSENSUS.

HOSTILE VERTICAL WIND SHEAR CONDITIONS OF 25 TO 30 KT THROUGH 96
HOURS ARE FORECAST TO PERSIST...AND THESE UNFAVORABLE UPPER-LEVEL
CONDITIONS...COMBINED WITH STEADILY DECREASING SEA-SURFACE
TEMPERATURES...ARE EXPECTED TO CAUSE GRADUAL WEAKENING OF THE
CYCLONE THROUGHOUT THE FORECAST CYCLE WITH ISELLE POSSIBLY BECOMING
A NON-CONVECTIVE LOW PRESSURE SYSTEM BY 72-96 HOURS. THE OFFICIAL
INTENSITY FORECAST IS SIMILAR TO THE SHIPS INTENSITY MODEL.


FORECAST POSITIONS AND MAX WINDS

INITIAL 14/2100Z 17.8N 110.2W 40 KT
12HR VT 15/0600Z 18.3N 111.2W 40 KT
24HR VT 15/1800Z 18.9N 112.4W 35 KT
36HR VT 16/0600Z 19.5N 113.5W 35 KT
48HR VT 16/1800Z 19.8N 114.5W 30 KT
72HR VT 17/1800Z 20.0N 116.0W 30 KT
96HR VT 18/1800Z 20.0N 117.5W 25 KT
120HR VT 19/1800Z 20.0N 119.0W 20 KT

$$
FORECASTER STEWART/PASCH

[Chacor]

051
WTPZ45 KNHC 150234
TCDEP5
TROPICAL STORM ISELLE DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 PM PDT THU AUG 14 2008

THERE HAS BEEN VERY LITTLE CHANGE IN ISELLE'S CLOUD PATTERN THIS
EVENING. ENHANCED INFRARED IMAGERY AND AN AMSR-E MICROWAVE OVERPASS
DEPICT THAT THE SURFACE CIRCULATION IS BENEATH THE NORTHEASTERN
EDGE OF THE DEEP CONVECTION...DUE TO THE PERSISTENT 20 TO 30 KT OF
EASTERLY SHEAR. ALL OF THE AVAILABLE INTENSITY MODELS SUGGEST THAT
THE AFOREMENTIONED SHEAR ENVIRONMENT WILL CONTINUE TO AFFECT THE
CYCLONE THROUGH THE FORECAST PERIOD IN ADDITION TO GRADUALLY
DECREASING SEA-SURFACE TEMPERATURES. THIS SCENARIO IS REFLECTED IN
THE OFFICIAL INTENSITY FORECAST WHICH CALLS FOR ISELLE TO BECOME A
REMNANT LOW IN 2 DAYS.

INITIAL MOTION IS ESTIMATED AT 270/8...A LITTLE TO THE LEFT OF THE
PREVIOUS ADVISORY. WITH THE EXCEPTION OF NOGAPS...THE GLOBAL
MODELS CONTINUE TO REVEAL A NORTHWEST TRACK BIAS...POSSIBLY DUE TO
SOME BINARY INTERACTION WITH THE RATHER LARGE AREA OF LOW PRESSURE
A FEW HUNDRED MILES TO THE WEST-SOUTHWEST OF ISELLE.
CONSEQUENTLY...THE NHC TRACK FORECAST IS PLACED TO THE LEFT OF THE
MODEL CONSENSUS AND IS NUDGED TOWARD THE NOGAPS WHICH APPEARS TO BE
ACCURATELY DEPICTING THE LOW TO MID LAYER STEERING FLOW PRODUCED BY
A RIDGE EXTENDING WESTWARD FROM CENTRAL MEXICO.

FORECAST POSITIONS AND MAX WINDS

INITIAL 15/0300Z 17.7N 111.1W 40 KT
12HR VT 15/1200Z 18.0N 112.0W 40 KT
24HR VT 16/0000Z 18.4N 113.2W 35 KT
36HR VT 16/1200Z 18.8N 114.3W 30 KT
48HR VT 17/0000Z 19.1N 115.2W 25 KT...REMNANT LOW
72HR VT 18/0000Z 19.4N 116.5W 25 KT...REMNANT LOW
96HR VT 19/0000Z 19.5N 118.0W 20 KT...REMNANT LOW
120HR VT 20/0000Z 19.5N 119.5W 20 KT...REMNANT LOW

$$
FORECASTER ROBERTS/AVILA

[HURAKAN]

Poor Iselle. She's going to be sheared to death!

Code: Select all

                    *   EAST PACIFIC SHIPS INTENSITY FORECAST   *
                    *        GOES INPUT INCLUDED                *
                    *      ISELLE  EP102008  08/15/08  06 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    35    35    34    34    33    30    27    21    16   DIS   DIS   DIS   DIS
V (KT) LAND       35    35    34    34    33    30    27    21    16   DIS   DIS   DIS   DIS
V (KT) LGE mod    35    33    32    30    29    26    23    20    17    15   DIS   DIS   DIS

SHEAR (KTS)       24    30    31    30    33    29    27    30    35    29    29    28    26
SHEAR DIR         81    88   106   111   117   127   130   115   124   124   125   103   107
SST (C)         27.8  27.7  27.5  27.4  27.2  26.8  26.5  26.2  26.0  25.8  25.5  25.4  25.3
POT. INT. (KT)   141   139   137   136   134   129   126   122   120   118   115   114   113
200 MB T (C)   -53.0 -53.1 -53.1 -53.0 -53.1 -53.5 -53.2 -53.1 -53.0 -53.2 -52.8 -52.7 -52.7
TH_E DEV (C)       6     6     6     6     5     5     4     4     3     3     3     3     3
700-500 MB RH     74    74    74    70    68    64    62    55    57    52    51    45    43
GFS VTEX (KT)      6     5     5     5     5     4     4     3     3     2     3     2     4
850 MB ENV VOR    21    14    21    23    17    17    29    15    26    18    25    21    31
200 MB DIV        41    20    14    -7     2    -8    14     5     2    -6     3     0    -3
LAND (KM)        606   609   618   626   639   682   723   750   775   821   876   944   984
LAT (DEG N)     17.6  17.8  17.9  18.1  18.3  18.7  18.9  19.1  19.2  19.2  19.3  19.2  19.3
LONG(DEG W)    111.4 112.0 112.6 113.2 113.7 114.8 115.5 116.2 116.8 117.5 118.4 119.2 119.8
STM SPEED (KT)     6     6     6     6     6     5     3     3     3     4     4     3     3

  FORECAST TRACK FROM OFCI      INITIAL HEADING/SPEED (DEG/KT):275/  7      CX,CY:  -6/  1
  T-12 MAX WIND:  40            PRESSURE OF STEERING LEVEL (MB):  557  (MEAN=582)
  GOES IR BRIGHTNESS TEMP. STD DEV. 100-300 KM RAD:  21.5 (MEAN=18.0)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD:  66.0 (MEAN=65.7)

                        INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
                         6   12   18   24   36   48   60   72   84   96  108  120
                        ----------------------------------------------------------
  SAMPLE MEAN CHANGE     0.   0.   0.   1.   1.   1.   0.   0.  -1.  -1.  -2.  -2.
  SST POTENTIAL          1.   1.   2.   4.   6.   8.   9.  10.  11.  11.  10.   9.
  VERTICAL SHEAR         0.   0.  -1.  -2.  -4.  -8. -12. -17. -20. -22. -23. -24.
  PERSISTENCE           -1.  -2.  -3.  -4.  -5.  -5.  -5.  -5.  -4.  -4.  -3.  -2.
  200/250 MB TEMP.       0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.   0.   0.
  THETA_E EXCESS         0.  -1.  -1.  -2.  -3.  -4.  -5.  -6.  -7.  -8.  -9.  -9.
  700-500 MB RH          0.   1.   1.   2.   3.   3.   3.   3.   3.   3.   2.   2.
  GFS VORTEX TENDENCY    0.   0.  -1.  -1.  -2.  -2.  -4.  -3.  -4.  -4.  -4.  -2.
  850 MB ENV VORTICITY   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  200 MB DIVERGENCE      0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.   0.   0.   0.
  ZONAL STORM MOTION     0.   0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.  -1.
  STEERING LEVEL PRES    0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  DAYS FROM CLIM. PEAK   0.   0.   0.   0.   1.   1.   1.   2.   3.   3.   4.   4.
                        ----------------------------------------------------------
  SUB-TOTAL CHANGE      -1.  -1.  -2.  -3.  -5.  -8. -13. -18. -23. -26. -27. -26.

  SATELLITE ADJUSTMENTS ----------------------------------------------------------
  MEAN ADJUSTMENT        0.   0.  -1.  -1.  -1.  -2.  -2.  -2.  -1.  -1.  -1.  -1.
  GOES IR STD DEV        0.   1.   2.   2.   3.   3.   2.   2.   1.   1.   1.   1.
  GOES IR PIXEL COUNT    0.   0.   0.   0.  -1.  -1.  -1.  -1.   0.   0.   0.   0.
                        ----------------------------------------------------------
  TOTAL ADJUSTMENT       0.   1.   1.   1.   1.   0.   0.  -1.   0.   0.   0.   1.
                        ----------------------------------------------------------
  TOTAL CHANGE (KT)      0.  -1.  -1.  -2.  -5.  -8. -14. -19. -23. -25. -27. -25.

** E. PACIFIC 2008 RI INDEX EP102008     ISELLE 08/15/08  06 UTC **
           ( 25 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)
 
 12 HR PERSISTENCE (KT):  -5.0 Range:-20.0 to  45.0 Scaled/Wgted Val:  0.2/  0.3
 850-200 MB SHEAR (KT) :  29.6 Range: 18.5 to   1.6 Scaled/Wgted Val:  0.0/  0.0
 D200 (10**7s-1)       :  14.0 Range:-11.0 to 127.0 Scaled/Wgted Val:  0.2/  0.1
 POT = MPI-VMAX (KT)   : 102.5 Range: 37.1 to 131.4 Scaled/Wgted Val:  0.7/  1.0
 850-700 MB REL HUM (%):  74.0 Range: 63.0 to  88.0 Scaled/Wgted Val:  0.4/  0.3
 % area w/pixels <-30 C:  56.0 Range: 26.0 to 100.0 Scaled/Wgted Val:  0.4/  0.1
 STD DEV OF IR BR TEMP :  16.4 Range: 35.4 to   2.7 Scaled/Wgted Val:  0.6/  0.9
 
 Prob of RI for 25 kt RI threshold=     4% is   0.3 times the sample mean(12.5%)
 Prob of RI for 30 kt RI threshold=     2% is   0.3 times the sample mean( 8.3%)
 Prob of RI for 35 kt RI threshold=     2% is   0.3 times the sample mean( 5.8%)

   ##         ANNULAR HURRICANE INDEX (AHI) EP102008     ISELLE 08/15/08  06 UTC         ##
   ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=3 NFAIL=4                          ##
   ## AHI=  0   (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##
   ##     ANNULAR INDEX RAN NORMALLY             

[HURAKAN]

640
WTPZ25 KNHC 151431
TCMEP5
TROPICAL STORM ISELLE FORECAST/ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
1500 UTC FRI AUG 15 2008

TROPICAL STORM CENTER LOCATED NEAR 17.7N 112.4W AT 15/1500Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 4 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1004 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 40NE 40SE 40SW 40NW.
12 FT SEAS.. 40NE 40SE 40SW 40NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 17.7N 112.4W AT 15/1500Z
AT 15/1200Z CENTER WAS LOCATED NEAR 17.6N 111.2W

FORECAST VALID 16/0000Z 18.0N 112.4W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 40NE 40SE 40SW 40NW.

FORECAST VALID 16/1200Z 18.3N 113.5W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 17/0000Z 18.4N 114.4W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 17/1200Z 18.4N 115.3W...REMNANT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 18/1200Z 18.5N 117.0W...REMNANT LOW
MAX WIND 20 KT...GUSTS 25 KT.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 200 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 19/1200Z 18.5N 118.5W...REMNANT LOW
MAX WIND 20 KT...GUSTS 25 KT.

OUTLOOK VALID 20/1200Z 18.5N 120.0W...REMNANT LOW
MAX WIND 20 KT...GUSTS 25 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.7N 112.4W

NEXT ADVISORY AT 15/2100Z

$$
FORECASTER STEWART/BEVEN

[HURAKAN]

309
WTPZ35 KNHC 151435
TCPEP5
BULLETIN
TROPICAL STORM ISELLE ADVISORY NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 AM PDT FRI AUG 15 2008

AT 800 AM PDT...1500 UTC...THE CENTER OF TROPICAL STORM ISELLE WAS
LOCATED NEAR LATITUDE 17.7 NORTH...LONGITUDE 112.4 WEST OR ABOUT 395
MILES...635 KM...SOUTH-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

ISELLE IS NOW MOVING TOWARD THE WEST-NORTHWEST NEAR 5 MPH...7
KM/HR...AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE
NEXT 48 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. GRADUAL WEAKENING IS EXPECTED DURING THE NEXT 48 HOURS AND
ISELLE COULD BECOME A TROPICAL DEPRESSION LATER TODAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB...29.65 INCHES.

REPEATING THE 800 AM PDT POSITION...17.7 N...112.4 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 5 MPH. MAXIMUM SUSTAINED WINDS...40
MPH. MINIMUM CENTRAL PRESSURE...1004 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
200 PM PDT.

$$
FORECASTER STEWART/BEVEN

[cycloneye]

The last advisory:

WTPZ45 KNHC 170230
TCDEP5
TROPICAL DEPRESSION ISELLE DISCUSSION NUMBER 15
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 PM PDT SAT AUG 16 2008

ALL THAT REMAINS OF ISELLE IS AN EXPOSED SWIRL OF CLOUDS WELL
DISPLACED FROM A RAPIDLY DIMINISHING SMALL AREA OF THUNDERSTORMS TO
THE WEST. CONSEQUENTLY...THE SYSTEM NO LONGER MEETS THE CRITERIA
OF A TROPICAL CYCLONE. HOWEVER...THERE MAY BE INTERMITTENT PERIODS
OF CONVECTIVE BURSTS DURING THE NEXT FEW DAYS...BUT IT IS BELIEVED
THAT THESE BRIEF EPISODES WILL NOT BE SIGNIFICANT ENOUGH TO
RE-DEVELOP THE REMNANTS OF ISELLE.

THE SYSTEM HAS BEEN DRIFTING NORTHWESTWARD THIS EVENING...HOWEVER
THE DYNAMICAL MODELS SUGGEST THAT A GRADUAL WEST-NORTHWESTWARD
MOTION SHOULD COMMENCE WITHIN THE NEXT 12 TO 24 HOURS.
AFTERWARD...THIS GENERAL MOTION SHOULD CONTINUE UNTIL THE
CIRCULATION DISSIPATES IN AROUND 4 DAYS...IF NOT SOONER.

THIS IS THE LAST ADVISORY ON ISELLE ISSUED BY THE NATIONAL HURRICANE
CENTER. FUTURE INFORMATION ON THE REMNANTS OF ISELLE CAN BE FOUND
IN HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER
SERVICE...UNDER AWIPS HEADER NFDHSFEPI AND WMO HEADER FZPN02 KWBC.

FORECAST POSITIONS AND MAX WINDS

INITIAL 17/0300Z 18.6N 112.7W 30 KT...REMNANT LOW
12HR VT 17/1200Z 18.7N 113.2W 25 KT...REMNANT LOW
24HR VT 18/0000Z 18.9N 114.1W 25 KT...REMNANT LOW
36HR VT 18/1200Z 19.0N 115.0W 25 KT...REMNANT LOW
48HR VT 19/0000Z 19.0N 115.8W 20 KT...REMNANT LOW
72HR VT 20/0000Z 19.0N 117.0W 20 KT...REMNANT LOW
96HR VT 21/0000Z...DISSIPATED

$$
FORECASTER ROBERTS/AVILA

[HURAKAN]

135
WHXX01 KMIA 221338
CHGE77
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1338 UTC FRI AUG 22 2008

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

EAST PACIFIC OBJECTIVE AIDS FOR

DISTURBANCE ISELLE (EP102008) 20080822 1200 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
080822 1200 080823 0000 080823 1200 080824 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 13.3N 125.3W 13.8N 125.8W 13.8N 126.3W 14.0N 127.2W
BAMD 13.3N 125.3W 13.3N 127.5W 13.0N 129.8W 12.6N 132.1W
BAMM 13.3N 125.3W 13.4N 126.2W 13.4N 127.3W 13.4N 128.5W
LBAR 13.3N 125.3W 13.0N 126.9W 13.0N 128.8W 13.3N 130.7W
SHIP 25KTS 28KTS 34KTS 34KTS
DSHP 25KTS 28KTS 34KTS 34KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
080824 1200 080825 1200 080826 1200 080827 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 14.3N 128.4W 15.1N 131.4W 15.5N 134.3W 15.3N 136.9W
BAMD 12.2N 134.3W 11.9N 137.8W 12.6N 140.9W 13.3N 142.6W
BAMM 13.5N 130.0W 14.3N 133.0W 15.1N 136.3W 15.2N 139.3W
LBAR 13.6N 132.9W 14.4N 137.5W 16.0N 141.8W 17.6N 144.8W
SHIP 38KTS 39KTS 44KTS 46KTS
DSHP 38KTS 39KTS 44KTS 46KTS

...INITIAL CONDITIONS...
LATCUR = 13.3N LONCUR = 125.3W DIRCUR = 250DEG SPDCUR = 5KT
LATM12 = 13.6N LONM12 = 124.2W DIRM12 = 248DEG SPDM12 = 5KT
LATM24 = 14.1N LONM24 = 123.0W
WNDCUR = 25KT RMAXWD = 35NM WNDM12 = 20KT
CENPRS = 1010MB OUTPRS = 1012MB OUTRAD = 120NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$
NNNN

Guess who's back?

[CrazyC83]

Wow, the first system this season in the western hemisphere to revive itself.

[HURAKAN]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1100 AM PDT FRI AUG 22 2008

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

A BROAD AREA OF LOW PRESSURE LOCATED A COUPLE HUNDRED MILES SOUTH OF
MANZANILLO MEXICO HAS BECOME A LITTLE BETTER ORGANIZED TODAY.
UPPER-LEVEL WINDS ARE FORECAST TO BECOME MORE FAVORABLE FOR
DEVELOPMENT...AND THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL
DEPRESSION AS IT MOVES TOWARD THE NORTHWEST AT 10 TO 15 MPH.
LOCALLY HEAVY RAINS AND GUSTY WINDS ARE POSSIBLE ALONG THE COAST
OF SOUTHWESTERN MEXICO AS THE SYSTEM PASSES OFFSHORE.

DISORGANIZED SHOWER AND THUNDERSTORM ACTIVITY CONTINUES NEAR THE
REMNANTS OF ISELLE...LOCATED ABOUT 1275 MILES SOUTHWEST OF CABO SAN
LUCAS MEXICO. REDEVELOPMENT OF THIS SYSTEM IS NOT EXPECTED DUE TO
STRONG UPPER-LEVEL WINDS. THIS SYSTEM IS FORECAST TO MOVE SLOWLY
WESTWARD DURING THE NEXT DAY OR TWO.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER BLAKE

[HURAKAN]

457
WHXX04 KWBC 221726
CHGQLM
ATTENTION...NATIONAL HURRICANE CENTER

NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR

TROPICAL DEPRESSION ISELLE 10E

INITIAL TIME 12Z AUG 22

DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT
REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD
NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC
OFFICIAL FORECAST.


FORECAST STORM POSITION

HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)

0 13.4 125.5 250./ 5.0
6 13.5 126.1 282./ 6.3
12 13.9 125.7 46./ 5.8
18 14.0 126.5 272./ 8.1
24 13.9 127.3 264./ 8.0
30 13.8 127.8 254./ 4.2
36 13.6 128.2 251./ 4.5
42 13.6 128.5 262./ 2.8
48 13.5 129.1 260./ 6.2
54 13.7 129.8 288./ 6.6
60 13.6 130.2 259./ 4.7
66 13.8 130.9 283./ 6.8
72 13.5 131.6 251./ 7.0
78 13.8 132.4 291./ 8.8
84 13.7 133.1 261./ 6.5
90 13.8 133.9 273./ 7.3
96 13.6 134.4 256./ 5.8
102 13.5 135.2 263./ 7.2
108 13.6 135.5 272./ 3.3
114 13.3 136.1 250./ 6.6
120 13.0 136.6 239./ 5.6
126 12.9 137.1 256./ 4.5