EPAC: Disturbance Iselle

[HURAKAN]

[HURAKAN]

Shear is not very favorable according to SHIPS.

Code: Select all

                    *   EAST PACIFIC SHIPS INTENSITY FORECAST   *
                    *        GOES INPUT INCLUDED                *
                    *      INVEST  EP962008  08/13/08  00 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    25    29    33    37    40    46    50    51    51    50    49    46    43
V (KT) LAND       25    29    33    37    40    46    50    51    51    50    49    46    43
V (KT) LGE mod    25    27    29    31    33    36    37    38    37    36    34    31    28

SHEAR (KTS)       18    19    21    19    23    20    25    13    13     8     8    10    11
SHEAR DIR         47    60    63    72    81    99   109   118   109   150   155   209   207
SST (C)         29.8  29.7  29.4  29.3  29.2  28.7  28.1  27.4  26.6  25.7  24.5  23.5  22.9
POT. INT. (KT)   162   162   159   158   157   151   145   138   129   119   107    96    89
200 MB T (C)   -52.9 -53.2 -53.3 -53.4 -53.0 -53.5 -53.1 -53.5 -53.3 -53.3 -53.2 -53.2 -53.3
TH_E DEV (C)      13    11    10    11    11     8     8     5     4     2     1     0     0
700-500 MB RH     72    77    73    72    70    73    68    68    64    63    60    56    49
GFS VTEX (KT)      5     5     5     5     4     3     2  LOST  LOST  LOST  LOST  LOST  LOST
850 MB ENV VOR    28    26     6    -4     2    -5    -3   -15    -6   -16   -11    -6     0
200 MB DIV        17    20    10    13    13     8    24     2    12    -1    -4   -11   -28
LAND (KM)        155   161   191   218   261   387   415   424   485   501   533   605   643
LAT (DEG N)     16.6  16.9  17.2  17.6  17.9  18.5  19.2  19.8  20.6  21.3  22.2  22.9  23.5
LONG(DEG W)    102.9 103.9 104.8 105.9 106.9 108.8 110.6 112.4 114.0 115.4 116.7 118.0 119.3
STM SPEED (KT)     8    10    10    11    10     9     9     9     8     8     7     7     6

  FORECAST TRACK FROM BAMM      INITIAL HEADING/SPEED (DEG/KT):310/  8      CX,CY:  -5/  5
  T-12 MAX WIND:  20            PRESSURE OF STEERING LEVEL (MB):  634  (MEAN=582)
  GOES IR BRIGHTNESS TEMP. STD DEV. 100-300 KM RAD:  21.1 (MEAN=18.0)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD:  72.0 (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          0.   1.   2.   5.  10.  17.  22.  26.  27.  26.  25.  22.
  VERTICAL SHEAR         1.   1.   2.   3.   2.   1.  -1.  -3.  -3.  -3.  -3.  -3.
  PERSISTENCE            1.   2.   2.   3.   3.   3.   3.   3.   2.   2.   2.   2.
  200/250 MB TEMP.       0.   0.   0.  -1.  -1.  -1.  -1.  -1.  -1.   0.   1.   2.
  THETA_E EXCESS         0.   1.   1.   1.   1.   1.   1.   0.  -2.  -3.  -5.  -6.
  700-500 MB RH          0.   1.   1.   2.   3.   4.   5.   5.   5.   4.   4.   3.
  GFS VORTEX TENDENCY    0.   0.   0.  -1.  -2.  -3.  -4.  -4.  -4.  -4.  -3.  -3.
  850 MB ENV VORTICITY   0.   0.   0.   0.   0.   0.  -1.  -1.  -2.  -2.  -3.  -3.
  200 MB DIVERGENCE      0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  ZONAL STORM MOTION     0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.  -1.  -1.  -1.
  STEERING LEVEL PRES    0.   0.   0.   0.   0.   0.   1.   1.   1.   1.   1.   1.
  DAYS FROM CLIM. PEAK   0.   0.   0.   0.   1.   1.   1.   2.   2.   3.   3.   4.
                        ----------------------------------------------------------
  SUB-TOTAL CHANGE       3.   6.   9.  11.  17.  21.  24.  25.  24.  22.  19.  16.

  SATELLITE ADJUSTMENTS ----------------------------------------------------------
  MEAN ADJUSTMENT        0.   0.  -1.  -1.  -1.  -2.  -2.  -2.  -1.  -1.  -1.  -1.
  GOES IR STD DEV        1.   2.   3.   4.   5.   5.   5.   3.   3.   2.   2.   2.
  GOES IR PIXEL COUNT    0.   0.   0.   0.   0.   0.  -1.   0.   0.   0.   0.   0.
                        ----------------------------------------------------------
  TOTAL ADJUSTMENT       1.   2.   3.   3.   4.   3.   2.   1.   1.   1.   2.   2.
                        ----------------------------------------------------------
  TOTAL CHANGE (KT)      4.   8.  12.  15.  21.  25.  26.  26.  25.  24.  21.  18.

** E. PACIFIC 2008 RI INDEX EP962008     INVEST 08/13/08  00 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:  0.4/  0.6
 850-200 MB SHEAR (KT) :  20.0 Range: 18.5 to   1.6 Scaled/Wgted Val:  0.0/  0.0
 D200 (10**7s-1)       :  14.6 Range:-11.0 to 127.0 Scaled/Wgted Val:  0.2/  0.1
 POT = MPI-VMAX (KT)   : 134.6 Range: 37.1 to 131.4 Scaled/Wgted Val:  1.0/  1.5
 850-700 MB REL HUM (%):  78.4 Range: 63.0 to  88.0 Scaled/Wgted Val:  0.6/  0.4
 % area w/pixels <-30 C:  57.0 Range: 26.0 to 100.0 Scaled/Wgted Val:  0.4/  0.1
 STD DEV OF IR BR TEMP :  18.0 Range: 35.4 to   2.7 Scaled/Wgted Val:  0.5/  0.8
 
 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) EP962008     INVEST 08/13/08  00 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) ##
   ##    NOTE: 1 INSTEAD OF 2 GOES FILES USED   

[HURAKAN]

BEGIN
NHC
invest_ep962008.invest
FSTDA
R
U
040
010
0000
200808130031
NONE
NOTIFY=ATRP
END
INVEST, EP, E, , , , , 96, 2008, DB, O, 2008080812, 9999999999, , , , , , METWATCH, , EP962008
EP, 96, 2008080800, , BEST, 0, 90N, 835W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008080806, , BEST, 0, 94N, 856W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008080812, , BEST, 0, 97N, 877W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1009, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008080818, , BEST, 0, 98N, 896W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1010, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008080900, , BEST, 0, 100N, 913W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008080906, , BEST, 0, 104N, 928W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008080912, , BEST, 0, 110N, 938W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1009, 180, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008080918, , BEST, 0, 120N, 945W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008081000, , BEST, 0, 121N, 951W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008081006, , BEST, 0, 122N, 955W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081012, , BEST, 0, 122N, 960W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081018, , BEST, 0, 126N, 968W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081100, , BEST, 0, 127N, 975W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008081106, , BEST, 0, 127N, 980W, 20, 1008, DB, 0, , 0, 0, 0, 0, 1011, 175, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008081112, , BEST, 0, 132N, 990W, 20, 1008, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081118, , BEST, 0, 139N, 996W, 20, 1009, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081200, , BEST, 0, 144N, 1001W, 20, 1009, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081206, , BEST, 0, 151N, 1009W, 20, 1009, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081212, , BEST, 0, 157N, 1017W, 20, 1007, DB, 0, , 0, 0, 0, 0,
EP, 96, 2008081218, , BEST, 0, 161N, 1026W, 25, 1007, DB, 0, , 0, 0, 0, 0, 1012, 150, 60, 0, 0, E, 0, , 0, 0, INVEST, M,
EP, 96, 2008081300, , BEST, 0, 166N, 1029W, 25, 1007, DB, 34, NEQ, 0, 0, 0, 0, 1010, 150, 60, 0, 0, E, 0, , 0, 0, INVEST, M,

[HURAKAN]

Looking much better.

[HURAKAN]

939
ABPZ20 KNHC 131147
TWOEP
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
500 AM PDT WED AUG 13 2008

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

THUNDERSTORM ACTIVITY ASSOCIATED WITH AN AREA OF LOW PRESSURE
CENTERED ABOUT 200 MILES SOUTH OF MANZANILLO MEXICO HAS INCREASED
IN ORGANIZATION THIS MORNING. ENVIRONMENTAL CONDITIONS APPEAR
SOMEWHAT FAVORABLE FOR TROPICAL CYCLONE FORMATION AND THIS SYSTEM
COULD BECOME A TROPICAL DEPRESSION LATER TODAY OR TONIGHT. RAINS
ALONG THE SOUTHWEST COAST OF MEXICO SHOULD DIMINISH AS THE SYSTEM
MOVES WEST-NORTHWESTWARD AT 10 TO 15 MPH.

THUNDERSTORM ACTIVITY ASSOCIATED WITH AN AREA OF LOW PRESSURE
LOCATED ABOUT 800 MILES SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA MEXICO REMAINS DISORGANIZED. UPPER-LEVEL WINDS ARE
EXPECTED TO REMAIN UNFAVORABLE FOR TROPICAL CYCLONE FORMATION OVER
THE NEXT COUPLE OF DAYS AS THE LOW MOVES SLOWLY WESTWARD.

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

$$
FORECASTER PASCH/BROW

[HURAKAN]

[HURAKAN]

664
WHXX01 KMIA 131259
CHGE77
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1259 UTC WED AUG 13 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

TROPICAL CYCLONE TEN (EP102008) 20080813 1200 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
080813 1200 080814 0000 080814 1200 080815 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 16.2N 105.3W 16.9N 106.4W 17.4N 107.3W 18.1N 108.1W
BAMD 16.2N 105.3W 16.6N 107.7W 17.2N 110.0W 18.0N 112.4W
BAMM 16.2N 105.3W 16.9N 107.0W 17.5N 108.7W 18.3N 110.3W
LBAR 16.2N 105.3W 16.7N 107.4W 17.4N 109.6W 18.2N 111.9W
SHIP 30KTS 36KTS 42KTS 46KTS
DSHP 30KTS 36KTS 42KTS 46KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
080815 1200 080816 1200 080817 1200 080818 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 18.5N 108.9W 19.6N 110.6W 20.5N 112.4W 21.3N 114.6W
BAMD 18.9N 114.9W 20.9N 119.6W 22.6N 123.7W 23.9N 127.1W
BAMM 18.9N 111.9W 20.1N 115.1W 21.4N 118.5W 22.2N 122.4W
LBAR 19.0N 114.2W 20.5N 118.4W 22.4N 122.3W 24.9N 125.0W
SHIP 47KTS 43KTS 37KTS 31KTS
DSHP 47KTS 43KTS 37KTS 31KTS

...INITIAL CONDITIONS...
LATCUR = 16.2N LONCUR = 105.3W DIRCUR = 275DEG SPDCUR = 9KT
LATM12 = 16.2N LONM12 = 103.6W DIRM12 = 273DEG SPDM12 = 9KT
LATM24 = 15.7N LONM24 = 101.7W
WNDCUR = 30KT RMAXWD = 30NM WNDM12 = 25KT
CENPRS = 1005MB OUTPRS = 1008MB OUTRAD = 150NM SDEPTH = D
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$
NNNN

[Chacor]

444
WTPZ45 KNHC 131435
TCDEP5
TROPICAL DEPRESSION TEN-E DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 AM PDT WED AUG 13 2008

NIGHTTIME VISIBLE AND INFRARED SATELLITE IMAGERY...PLUS A 13/1017Z
TRMM MICROWAVE OVERPASS...INDICATE THE TROPICAL DISTURBANCE
LOCATED ABOUT 185 NMI SOUTH-SOUTHWEST OF MANZANILLO MEXICO HAS
BECOME MUCH BETTER ORGANIZED AND HAS DEVELOPED INTO TROPICAL
DEPRESSION TEN-E. CURVED BANDING NOTED IN THE TRMM OVERPASS
SUGGESTS THIS SYSTEM MAY ALREADY BE NEAR TROPICAL STORM
STRENGTH...BUT THE RAPID CONVECTIVE ORGANIZATION MAY NOT HAVE
TRANSLATED INTO AN INCREASE IN THE SURFACE WINDS.

THE INITIAL MOTION ESTIMATE IS 280/09 KT. TROPICAL DEPRESSION 10-E
IS EXPECTED TO MOVE IN A GENERAL WEST OR WEST-NORTHWESTWARD
DIRECTION AS THE CYCLONE IS STEERED BY A DEEP-LAYERED RIDGE
SITUATED TO THE NORTH OF THE SYSTEM. THE LAST GFDL MODEL RUN
APPEARS TO BE AN OUTLIER BACK TAKING THE DEPRESSION NORTHWARD
TOWARD SOUTHERN BAJA CALIFORNIA. THE REST OF THE NHC MODEL SUITE
TAKES THE SYSTEM SLOWLY WEST-NORTHWESTWARD. THE OFFICIAL FORECAST
TRACK IS ALONG THE EXTREME SOUTHERN PORTION OF THE GUIDANCE
ENVELOPE IN ANTICIPATION OF INCREASING VERTICAL WIND SHEAR POSSIBLY
WEAKENING THE CYCLONE IN THE LATER PERIODS...WHICH WOULD CAUSE THE
SYSTEM TO BE STEERED MORE WESTWARD BY THE LOW-LEVEL EASTERLIES.

ALTHOUGH THE OVERNIGHT BURST OF CONVECTION WAS IMPRESSIVE AND
HELPED TO QUICKLY SPIN UP THE WIND FIELD...THIS DEVELOPMENT PROCESS
MAY BE SHORT-LIVED. THE CONVECTIVE BURST MAY HAVE BEEN IN RESPONSE
TO THE DIVERGENT REGION OF AN APPROACHING UPPER-LEVEL JET MAXIMUM
MOVING ACROSS SOUTH-CENTRAL MEXICO. HOWEVER...WATER VAPOR IMAGERY
AND DERIVED WIND FIELDS ALSO INDICATE THAT THE NOSE OF THE 40-50 KT
UPPER-LEVEL JET SHOULD BE ENCROACHING ON THE CYCLONE FROM THE
NORTHEAST DURING THE NEXT 24 HOURS...WHICH SHOULD SIGNIFICANTLY
INCREASE THE VERTICAL WIND SHEAR ACROSS THE SYSTEM. FOR THIS
REASON...ONLY MODEST INTENSIFICATION IS FORECAST THROUGH DAY 2 WITH
GRADUAL WEAKENING EXPECTED AFTERWARD AS THE CYCLONE MOVES OVER
COOLER WATER.


FORECAST POSITIONS AND MAX WINDS

INITIAL 13/1500Z 16.3N 105.8W 30 KT
12HR VT 14/0000Z 16.7N 107.2W 35 KT
24HR VT 14/1200Z 17.3N 109.0W 40 KT
36HR VT 15/0000Z 17.7N 110.4W 45 KT
48HR VT 15/1200Z 18.0N 111.9W 45 KT
72HR VT 16/1200Z 18.4N 114.0W 45 KT
96HR VT 17/1200Z 19.0N 116.0W 40 KT
120HR VT 18/1200Z 19.0N 118.0W 35 KT

$$
FORECASTER STEWART/BROWN

[Chacor]

TD 10E prediction challenge.

[Cyclenall]

The 3rd paragraph of the discussion had very intresting wording. As Derek said, is this from the old 96E that never got going last week? It took ages to finally spin up.

[HURAKAN]

Looking great.

[HURAKAN]

EP, 10, 2008081318, , BEST, 0, 165N, 1063W, 35, 1003, TS,

Hello Iselle.

[KWT]

Not all that surprising given the decent convection over the center.

[HURAKAN]

729
WTPZ45 KNHC 132051
TCDEP5
TROPICAL STORM ISELLE DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
200 PM PDT WED AUG 13 2008

VISIBLE AND INFRARED SATELLITE IMAGERY INDICATES THAT THE DEPRESSION
HAS ACQUIRED ENOUGH CONVECTIVE BANDING FEATURES... PRIMARILY IN THE
SOUTHERN SEMICIRCLE...FOR THE SYSTEM TO BE UPGRADED TO TROPICAL
STORM ISELLE. THIS INTENSITY IS SUPPORTED BY A DVORAK INTENSITY
ESTIMATE OF T2.5/35 KT FROM TAFB.

THE INITIAL MOTION ESTIMATE IS 285/09 KT. THERE IS NO SIGNIFICANT
CHANGE TO THE PREVIOUS FORECAST TRACK OR REASONING. TROPICAL STORM
ISELLE IS EXPECTED TO MOVE IN A GENERAL WEST-NORTHWESTWARD
DIRECTION THROUGH 72 HOURS...AND THEN TURN MORE WESTWARD AFTER THAT
AS THE CYCLONE WEAKENS AND IS STEERED MORE BY THE LOW-LEVEL
EASTERLIES. THE LATEST GFDL AND GFS MODEL RUNS TAKE A VERY WEAK
SYSTEM NORTHWARD TOWARD SOUTHERN BAJA CALIFORNIA AFTER 72
HOURS...WHEREAS THE REMAINDER OF THE NHC MODELS TAKE THE SYSTEM
SLOWLY WEST-NORTHWESTWARD THEN WESTWARD. THE OFFICIAL FORECAST
TRACK REMAINS ALONG THE EXTREME SOUTHERN PORTION OF THE GUIDANCE
ENVELOPE.

AN APPROACHING UPPER-LEVEL JET MAXIMUM TO THE NORTHEAST OF ISELLE IS
ALREADY BEGINNING TO INCREASE THE VERTICAL WIND SHEAR ACROSS THE
CYCLONE. THE SHIPS INTENSITY MODEL MAINTAINS 20-25 KT OF SHEAR
ACROSS ISELLE THROUGHOUT THE PERIOD...SO ONLY MODEST STRENGTHENING
IS FORECAST. BY 96 HOURS...ISELLE WILL BE MOVING OVER COOLER WATERS
THAT ARE EXPECTED TO INDUCE GRADUAL WEAKENING. THE OFFICIAL
INTENSITY FORECAST IS SLIGHTLY LOWER THAN THE SHIPS MODEL.


FORECAST POSITIONS AND MAX WINDS

INITIAL 13/2100Z 16.6N 106.7W 35 KT
12HR VT 14/0600Z 17.1N 108.1W 40 KT
24HR VT 14/1800Z 17.5N 109.7W 45 KT
36HR VT 15/0600Z 17.9N 111.2W 45 KT
48HR VT 15/1800Z 18.2N 112.5W 45 KT
72HR VT 16/1800Z 18.6N 114.5W 45 KT
96HR VT 17/1800Z 19.0N 116.5W 40 KT
120HR VT 18/1800Z 19.0N 118.5W 35 KT

$$
FORECASTER STEWART/FRANKLIN

[HURAKAN]

941
WTPZ35 KNHC 132053
TCPEP5
BULLETIN
TROPICAL STORM ISELLE ADVISORY NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
200 PM PDT WED AUG 13 2008

...TROPICAL DEPRESSION STRENGTHENS INTO TROPICAL STORM ISELLE...

AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL STORM ISELLE WAS
LOCATED NEAR LATITUDE 16.6 NORTH...LONGITUDE 106.7 WEST OR ABOUT 230
MILES...370 KM...SOUTHWEST OF MANZANILLO MEXICO.

ISELLE IS MOVING TOWARD THE WEST-NORTHWEST NEAR 10 MPH...17 KM/HR...
AND A MOTION TO THE WEST-NORTHWEST AWAY FROM MEXICO IS EXPECTED
DURING THE NEXT 48 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. SOME SLOW STRENGTHENING IS FORECAST DURING THE NEXT 24 TO 48
HOURS.

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

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB...29.62 INCHES.

REPEATING THE 200 PM PDT POSITION...16.6 N...106.7 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 10 MPH. MAXIMUM SUSTAINED WINDS...40
MPH. MINIMUM CENTRAL PRESSURE...1003 MB.

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

$$
FORECASTER STEWART/FRANKLIN

[Ad Novoxium]

Wow, they upgraded it so fast that some pages still have the T. D. Ten moniker, even the Iselle discussions.

[HURAKAN]

[HURAKAN]

Iselle may be meeting Mr. Shear.

[HURAKAN]

142
WTPZ35 KNHC 140251
TCPEP5
BULLETIN
TROPICAL STORM ISELLE ADVISORY NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 PM PDT WED AUG 13 2008

AT 800 PM PDT...0300 UTC...THE CENTER OF TROPICAL STORM ISELLE WAS
LOCATED NEAR LATITUDE 17.4 NORTH...LONGITUDE 107.7 WEST OR ABOUT 250
MILES...400 KM...WEST-SOUTHWEST OF MANZANILLO MEXICO AND ABOUT 405
MILES...655 KM...SOUTH-SOUTHEAST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

ISELLE IS MOVING TOWARD THE WEST-NORTHWEST NEAR 12 MPH...19 KM/HR...
AND THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS...WITH
A REDUCTION IN FORWARD SPEED EXPECTED ON FRIDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 24
HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 35 MILES...55 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB...29.62 INCHES.

REPEATING THE 800 PM PDT POSITION...17.4 N...107.7 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...40
MPH. MINIMUM CENTRAL PRESSURE...1003 MB.

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

$$
FORECASTER FRANKLIN

[HURAKAN]

490
WTPZ45 KNHC 140251
TCDEP5
TROPICAL STORM ISELLE DISCUSSION NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP102008
800 PM PDT WED AUG 13 2008

AN ASCAT PASS AT 1630Z THIS AFTERNOON PLACED THE CENTER OF ISELLE ON
THE NORTHEASTERN EDGE OF A SMALL BLOB OF CONVECTION...FARTHER NORTH
THAN PREVIOUSLY ESTIMATED...AND LACKING ANY EVIDENCE TO THE
CONTRARY I'M ASSUMING THAT RELATIVE LOCATION STILL HOLDS. THIS
REQUIRES A NORTHWARD ADJUSTMENT OF THE PREVIOUS TRACK WITH AN
INITIAL MOTION ESTIMATE OF 295/10. ISELLE IS CURRENTLY LOCATED TO
THE SOUTH OF MID- TO UPPER-LEVEL HIGH PRESSURE OVER NORTH-CENTRAL
MEXICO...BUT THE TRACK FORECAST IS UNUSUALLY DIFFICULT...AS ISELLE
IS IN A HIGH-SHEAR ENVIRONMENT AND THE GUIDANCE IS HIGHLY DIVERGENT.
MOST OF THE GUIDANCE CALLS FOR A CONTINUED TRACK TO THE
WEST-NORTHWEST OR NORTHWEST FOR AT LEAST THE NEXT COUPLE OF DAYS AS
ISELLE APPROACHES THE WESTERN PERIPHERY OF THE AFOREMENTIONED HIGH
PRESSURE. THE GFDL...HOWEVER...CALLS FOR ISELLE TO SUCCUMB TO THE
SHEAR WITHIN A DAY OR SO...TAKING ITS MID-LEVEL VORTICITY WESTWARD
AND ITS LOW-LEVEL REMNANTS NORTHWARD TOWARD THE BAJA PENINSULA.
THE LATTER TRACK SCENARIO IS BEING DISCOUNTED FOR NOW...NOT SO MUCH
BECAUSE IT IS UNLIKELY...BUT BECAUSE IF SUCH A TRACK DOES
MATERIALIZE THERE SHOULD BE VERY LITTLE OF ISELLE LEFT. IF ISELLE
IS STILL A TROPICAL CYCLONE IN 48-72 HOURS...IT WILL HAVE HAD TO
FOLLOW A DEEPER LAYER FLOW AND THAT IS THE ASSUMPTION REFLECTED IN
THE TRACK GIVEN BELOW. THE OFFICIAL FORECAST HAS BEEN SHIFTED
NORTHWARD OF THE PREVIOUS ADVISORY TRACK AND IS IN BEST AGREEMENT
WITH THE GFS AND MEDIUM BAM THROUGH 48 HOURS...AND SHOWS RELATIVELY
LITTLE MOTION AFTER THAT IN DEFERENCE TO THE MODEL SPREAD. IT
SHOULD BE NOTED THAT THE MODEL CONSENSUS LIES EVEN FARTHER TO THE
NORTH AND EAST OF THE OFFICIAL FORECAST.

THE INITIAL INTENSITY REMAINS 35 KT...WITH DVORAK INTENSITY
ESTIMATES OF 35 AND 45 KT FROM SAB AND TAFB...RESPECTIVELY.
NORTHEASTERLY OR EASTERLY SHEAR IS FORECAST BY THE GLOBAL MODELS TO
CONTINUE FOR MOST OF THE FIVE-DAY FORECAST PERIOD...AND NONE OF THE
AVAILABLE INTENSITY GUIDANCE SUGGESTS MUCH STRENGTHENING. THE
OFFICIAL FORECAST CALLS FOR VERY LITTLE CHANGE IN STRENGTH UNTIL
AFTER 72 HOURS WHEN ISELLE IS EXPECTED TO CROSS THE 26C SST
ISOTHERM. AS NOTED ABOVE...IT IS QUITE POSSIBLE THAT ISELLE WILL
NOT LAST THAT LONG.


FORECAST POSITIONS AND MAX WINDS

INITIAL 14/0300Z 17.4N 107.7W 35 KT
12HR VT 14/1200Z 17.9N 108.9W 40 KT
24HR VT 15/0000Z 18.4N 110.3W 40 KT
36HR VT 15/1200Z 19.0N 111.3W 40 KT
48HR VT 16/0000Z 19.8N 112.5W 40 KT
72HR VT 17/0000Z 20.5N 114.0W 40 KT
96HR VT 18/0000Z 21.0N 115.5W 35 KT
120HR VT 19/0000Z 21.0N 117.0W 30 KT

$$
FORECASTER FRANKLIN