ATL: Tropical Depression Fay

[Chris_in_Tampa]

NHC has revised some of their coordinates in the best track database.

Was...

AL, 92, 2008081312, , BEST, 0, 163N, 570W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 60, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081318, , BEST, 0, 165N, 580W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 80, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081400, , BEST, 0, 167N, 590W, 25, 1009, DB, 34, NEQ, 0, 0, 0, 0, 1012, 150, 80, 0, 0, L, 0, , 0, 0, INVEST, M,

Now....

AL, 92, 2008081312, , BEST, 0, 165N, 565W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 60, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081318, , BEST, 0, 169N, 573W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 80, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081400, , BEST, 0, 172N, 581W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 150, 80, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081406, , BEST, 0, 175N, 590W, 30, 1007, DB, 0, , 0, 0, 0, 0,

[KWT]

Yeah they were probably too far west trying to focus on that weak little low that was present to the west of the deep convection yesterday. Anyway now it does look like its finally getting better organised, just a matter of time before it develops a LLC I'd have thought.

[blp]

6:15UTC

[kurtpage]

14/0545 UTC 16.7N 61.3W T1.0/1.0 92L -- Atlantic Ocean

[KWT]

Nice deep convection there blp, just a waiting game now to see if anything comes of it really.

[blp]

14/0545 UTC 16.7N 61.3W T1.0/1.0 92L -- Atlantic Ocean

Interesting they think it is that far West. I was thinking 59 or 59.5. Did they get that from recon or was that a sat estimate?

[kurtpage]

14/0545 UTC 16.7N 61.3W T1.0/1.0 92L -- Atlantic Ocean

Interesting they think it is that far West. I was thinking 59 or 59.5. Did they get that from recon or was that a sat estimate?

Sat Estimate....

[KWT]

They must still be tracking that little weak low area that we had yesterday displaced well to the west still, we shall see when the vis comes up whether anything is actually that far west, got a feeling a new LLC will form very soon and become dominant under that convection.

[Chris_in_Tampa]

Those dvorak position estimates are wrong and way off. They are at least 1.0 lower on the T number than it should be and the coords are way off. The NHC has been adjusting the coordinates. They have made two revisions in the past 30 minutes to the coords for the past 24 hours.

AL, 92, 2008081306, , BEST, 0, 161N, 553W, 25, 1009, DB, 0, , 0, 0, 0, 0,
AL, 92, 2008081312, , BEST, 0, 164N, 563W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 60, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081318, , BEST, 0, 167N, 573W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 220, 80, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081400, , BEST, 0, 170N, 583W, 25, 1009, DB, 0, , 0, 0, 0, 0, 1012, 150, 80, 0, 0, L, 0, , 0, 0, INVEST, M,
AL, 92, 2008081406, , BEST, 0, 173N, 593W, 30, 1007, DB, 34, NEQ, 0, 0, 0, 0, 1012, 150, 60, 0, 0, L, 0, , 0, 0, INVEST, M,

[RL3AO]

Code: Select all

                    *   ATLANTIC SHIPS INTENSITY FORECAST       *
                    *        GOES/OHC INPUT INCLUDED            *
                    *      INVEST  AL922008  08/14/08  06 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    30    33    37    40    44    50    58    66    72    78    78    80    78
V (KT) LAND       30    33    37    40    44    50    58    66    72    78    78    80    78
V (KT) LGE mod    30    33    36    40    43    51    58    65    73    81    86    87    86

SHEAR (KTS)        0     2     6     4    10    13     4     4     4     9    17    12    13
SHEAR DIR        169   235   306   352     4    25   350    46   237   206   238   234   272
SST (C)         28.4  28.4  28.4  28.5  28.6  28.8  28.8  28.8  28.8  29.0  29.3  29.7  29.8
POT. INT. (KT)   143   143   143   145   146   149   149   148   148   151   155   161   162
ADJ. POT. INT.   137   137   138   140   141   142   140   137   135   136   138   140   138
200 MB T (C)   -54.0 -53.9 -53.8 -53.7 -53.5 -53.7 -53.6 -53.4 -53.6 -53.6 -53.7 -53.8 -53.7
TH_E DEV (C)      12    12    12    13    12    12    12    12    12    11    11    10    11
700-500 MB RH     50    48    46    45    48    48    53    51    48    51    49    50    44
GFS VTEX (KT)      8     7     7     7     7     6     6     7     6     7     5     6     5
850 MB ENV VOR     0    -1   -10   -11   -15   -16   -22   -33   -37   -23   -29   -19   -23
200 MB DIV        -9    -4    -4   -17   -19   -13     2    29    18    49     9    -3   -23
LAND (KM)        686   554   423   279   141    88    56    66   133   160   237   296   322
LAT (DEG N)     17.3  17.7  18.0  18.3  18.6  19.3  19.9  20.4  21.1  22.1  23.2  24.2  24.7
LONG(DEG W)     59.3  60.5  61.7  63.1  64.4  67.0  69.4  71.5  73.2  74.6  75.6  76.3  76.7
STM SPEED (KT)    11    12    13    13    13    12    11     9     8     8     6     5     3
HEAT CONTENT      62    63    62    53    59    71    61    59    68    61    66    73    73

  FORECAST TRACK FROM BAMM      INITIAL HEADING/SPEED (DEG/KT):290/ 10      CX,CY:  -8/  3
  T-12 MAX WIND:  25            PRESSURE OF STEERING LEVEL (MB):  513  (MEAN=625)
  GOES IR BRIGHTNESS TEMP. STD DEV. 100-300 KM RAD:  29.9 (MEAN=20.0)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD:  41.0 (MEAN=68.6)

                        INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
                         6   12   18   24   36   48   60   72   84   96  108  120
                        ----------------------------------------------------------
  SAMPLE MEAN CHANGE     1.   2.   3.   4.   6.   8.   9.  10.  11.  12.  12.  13.
  SST POTENTIAL          0.   1.   1.   2.   6.  11.  17.  21.  25.  28.  30.  32.
  VERTICAL SHEAR         1.   3.   5.   6.   8.  11.  13.  14.  15.  13.  13.  12.
  PERSISTENCE            1.   2.   2.   3.   3.   3.   2.   2.   2.   1.   1.   0.
  200/250 MB TEMP.       0.   0.   0.   0.   0.   0.   0.   0.   0.   1.   1.   1.
  THETA_E EXCESS         0.   0.   0.   1.   1.   1.   1.   1.   1.   1.   1.   1.
  700-500 MB RH          0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  GFS VORTEX TENDENCY    0.   0.  -1.  -1.  -2.  -2.  -2.  -3.  -2.  -4.  -3.  -4.
  850 MB ENV VORTICITY   0.   0.  -1.  -1.  -1.  -2.  -3.  -3.  -4.  -4.  -5.  -5.
  200 MB DIVERGENCE      0.  -1.  -1.  -2.  -2.  -3.  -3.  -3.  -3.  -3.  -3.  -3.
  ZONAL STORM MOTION     0.   0.   0.   1.   1.   1.   1.   2.   2.   2.   2.   2.
  STEERING LEVEL PRES    0.   0.   1.   1.   1.   2.   2.   2.   3.   2.   2.   2.
  DAYS FROM CLIM. PEAK   0.   0.   0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.
                        ----------------------------------------------------------
  SUB-TOTAL CHANGE       4.   7.  11.  15.  21.  29.  37.  43.  49.  49.  51.  50.

  SATELLITE ADJUSTMENTS ----------------------------------------------------------
  MEAN ADJUSTMENT        0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.  -1.  -1.  -2.
  GOES IR STD DEV        0.   1.   1.   1.   1.   1.   1.   0.   0.   0.   0.   0.
  GOES IR PIXEL COUNT    0.  -1.  -1.  -1.  -1.  -1.   0.   1.   1.   1.   1.   0.
  OCEAN HEAT CONTENT     0.   0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.   0.
                        ----------------------------------------------------------
  TOTAL ADJUSTMENT       0.   0.   0.  -1.  -1.  -1.  -1.  -1.  -1.  -1.  -1.  -2.
                        ----------------------------------------------------------
  TOTAL CHANGE (KT)      3.   7.  10.  14.  20.  28.  36.  42.  48.  48.  50.  48.

   ** 2008 ATLANTIC RI INDEX AL922008     INVEST 08/14/08  06 UTC **
           ( 25 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)
 
 12 HR PERSISTENCE (KT):   5.0 Range:-45.0 to  30.0 Scaled/Wgted Val:  0.7/  1.2
 850-200 MB SHEAR (KT) :   4.3 Range: 35.1 to   3.2 Scaled/Wgted Val:  1.0/  1.5
 D200 (10**7s-1)       : -10.6 Range:-20.0 to 149.0 Scaled/Wgted Val:  0.1/  0.1
 POT = MPI-VMAX (KT)   : 108.7 Range: 25.1 to 130.7 Scaled/Wgted Val:  0.8/  0.9
 850-700 MB REL HUM (%):  64.8 Range: 56.0 to  88.0 Scaled/Wgted Val:  0.3/  0.1
 % area w/pixels <-30 C:  37.0 Range: 17.0 to 100.0 Scaled/Wgted Val:  0.2/  0.1
 STD DEV OF IR BR TEMP :  22.8 Range: 35.1 to   3.2 Scaled/Wgted Val:  0.4/  0.5
 Heat content (KJ/cm2) :  59.8 Range:  0.0 to 132.0 Scaled/Wgted Val:  0.5/  0.0
 
 Prob of RI for 25 kt RI threshold=    21% is   1.7 times the sample mean(12.3%)
 Prob of RI for 30 kt RI threshold=    13% is   1.6 times the sample mean( 7.8%)
 Prob of RI for 35 kt RI threshold=     1% is   0.3 times the sample mean( 4.5%)

   ##         ANNULAR HURRICANE INDEX (AHI) AL922008     INVEST 08/14/08  06 UTC         ##
   ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=4 NFAIL=3                          ##
   ## AHI=  0   (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##
   ##     ANNULAR INDEX RAN NORMALLY             

Shear remains low and the RI prob shot up.

[Matt-hurricanewatcher]

If current trends hold up there is no question unless I'm going blind that this will be a depression later today or within the next 12-24 hours. Nice inflow developing with very well organized convection. Nice system!!!

I would say currently this system is 80 percent closed. All it needs is a west wind...

If the environment becomes more favorable and this stays north of Hati this could be a system of interest.

[Honeyko]

It's clearly in runaway intensification mode now.

TD, if you please, before it's a TS, would be lovely.

[wzrgirl1]

me thinks this could be upgraded by 5 am

[RL3AO]

me thinks this could be upgraded by 5 am

Could be upgraded at 5am Friday.

[wxmann_91]

While not in a "runaway intensification mode", some pretty decent outflow channels are going to develop in the next 24-36 hr, you can see the classic shape on the 36 hr GFS 700mb map (gotta look at 200mb to see the ULL's that will provide the channels). I think TD later today.

[Matt-hurricanewatcher]

This post is unoffical and has no meaning what so ever. If you read it you may go blind for doing so at least to some people that don't care to read anything I say.


I believe this will be a depression by 5pm est today. We just have to get a LLC to form! Once that is done the upper level environment should be favorable enough to allow it to start strengthing, in which case I expect tropical storm Fay by 5am Friday morning. If the Gfs and other models are right on developing outflow models; with the Gfdl showing a environment favorable enough to support cat4 strength, I would watch this very carefully. This if it stays north of Hati and a east trough don't come down in hell the helll out of it this could be possibly our second Major hurricane of 2008. As for track a west to west-northwest track on the buttom side of the high during the next 48-72 hours is very reasonable. Afterwards we will have to watch for weaknesses or troughs to pick this up...In which case if it gets inside of 70 west the east coast has to watch this carefully.


I will "forecast"
80% Depression
50% Tropical storm
30% Hurricane
20% Major hurricane
.01 Cat5

Depression that 80 percent is for any chance that it fades like it likes to do over night tonight. Remember things can change fast over the tropics.

It would not suprize me if this thing bombed or faded.

[wzrgirl1]

oh my I have to get up in 1 and 1/2 hours should I bother even sleeping? Looks as if it's getting it's act together this morning for sure. I expect a td some time today maybe 5:00 a.m. was a little premature. Going to get shut eye for a little...see ya'all later

[Texashawk]

me thinks this could be upgraded by 5 am

Could be upgraded at 5am Friday.

You serious? Why do you think it'll take that long??

[RL3AO]

me thinks this could be upgraded by 5 am

Could be upgraded at 5am Friday.

You serious? Why do you think it'll take that long??

It has to completely develop and close a low level circulation. It can now start to do it because of the increased thunderstorms.

[Honeyko]

While not in a "runaway intensification mode"...

Er, how much more impressive does an Invest have to be over the course of six hours to meet that criteria?

some pretty decent outflow channels are going to develop in the next 24-36 hr, you can see the classic shape on the 36 hr GFS 700mb map (gotta look at 200mb to see the ULL's that will provide the channels). I think TD later today.

80c tops are going to exhaust over the head of everything.

Whereas in previous days, 92 was being smothered by exhaust from SE coastal trough and Central American convection, now it's turn-table time. You just watch her anticyclone explode in all directions, and kill convective activity at its periphery.

(My preliminary hunch is that soon-to-be Fay will run right over PR and then beat her brains out on DR/Haiti; possible Gulf menace if whatever is left can manage to spin up south of Cuba rather than grind up the whole length of that island. E.g., Hurricane Frederick track.)