Ex Invest 99L Model Runs

[Aric Dunn]

00z GFS loop ... Keeps a strong ridge north of the system and brings it close to the islands

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[blp]

Looks like a weakness around 60W caused by the large trough exiting off the east coast.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... v_168l.gif

[RL3AO]

GFS doesn't stregthen it quickly like it did with Bertha therefore it doesn't show the early recurve.

[Aric Dunn]

GFS doesn't stregthen it quickly like it did with Bertha therefore it doesn't show the early recurve.

that and bertha had a weakness to pass by...

the ridge is much more extensive a recurve that early is unlikely with this system no matter the stregnth before 55 west.

[Ed Mahmoud]

In a semi-odd twist, Canadian keeps this as a healthy, but undeveloped wave, all the way to the islands.

Don't see TC specific SHIPS/BAM/GFDL guidance yet.


And the world above says "No Active Storms".

[Blown Away]

SFWMD Model Plot:
http://my.sfwmd.gov/portal/page?_pageid ... ema=PORTAL

[SouthFloridawx]

Aren't they running models on this Invest?

http://asp1.sbs.ohio-state.edu/tropical/atlantic/model/

[Mecklenburg]

some models are predicting it to move WSW right?

[SouthFloridawx]

716
WHXX01 KWBC 301209
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1209 UTC WED JUL 30 2008

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

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL982008) 20080730 0600 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
080730 0600 080730 1800 080731 0600 080731 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 14.6N 18.9W 15.8N 21.8W 16.9N 25.0W 18.0N 28.5W
BAMD 14.6N 18.9W 16.4N 21.6W 18.1N 24.4W 19.9N 27.6W
BAMM 14.6N 18.9W 16.2N 22.0W 17.6N 25.3W 18.9N 29.0W
LBAR 14.6N 18.9W 15.9N 21.1W 17.5N 23.5W 19.1N 26.5W
SHIP 20KTS 23KTS 27KTS 29KTS
DSHP 20KTS 23KTS 27KTS 29KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
080801 0600 080802 0600 080803 0600 080804 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 19.0N 32.2W 20.7N 39.2W 22.8N 45.6W 25.6N 50.8W
BAMD 21.8N 30.6W 25.6N 34.0W 26.9N 33.0W 24.4N 31.7W
BAMM 20.1N 32.7W 22.2N 39.2W 24.4N 44.6W 26.7N 48.1W
LBAR 20.6N 29.5W 23.2N 34.7W 25.7N 38.5W 27.7N 39.4W
SHIP 32KTS 37KTS 34KTS 33KTS
DSHP 32KTS 37KTS 34KTS 33KTS

...INITIAL CONDITIONS...
LATCUR = 14.6N LONCUR = 18.9W DIRCUR = 300DEG SPDCUR = 9KT
LATM12 = 13.7N LONM12 = 17.2W DIRM12 = 307DEG SPDM12 = 9KT
LATM24 = 12.8N LONM24 = 15.5W
WNDCUR = 20KT RMAXWD = 0NM WNDM12 = 20KT
CENPRS = 1007MB OUTPRS = 1009MB OUTRAD = 150NM SDEPTH = D
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$
NNNN

[Chacor]

And 12Z SHIPS...

Code: Select all

                    *   ATLANTIC SHIPS INTENSITY FORECAST       *
                    *     GOES AND/OR OHC INPUT MISSING         *
                    *      INVEST  AL982008  07/30/08  12 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    25    27    30    31    32    35    36    36    36    32    29    25    23
V (KT) LAND       25    27    30    31    32    35    36    36    36    32    29    25    23
V (KT) LGE mod    25    27    29    30    30    31    32    32    32    31    29    28    27

SHEAR (KTS)        8    11    14    15    16    18    15    23    26    27    24    20    14
SHEAR DIR        235   202   223   235   232   246   252   243   262   282   301    15    36
SST (C)         25.7  24.5  24.0  24.2  24.2  24.5  25.2  25.7  26.0  26.4  26.6  26.6  26.7
POT. INT. (KT)   113   104   101   102   102   104   109   112   115   118   119   116   116
ADJ. POT. INT.   109   101    97    99    99   100   103   104   105   106   103    97    96
200 MB T (C)   -53.5 -52.7 -53.3 -53.6 -53.6 -53.2 -53.7 -53.8 -54.2 -54.4 -54.7 -54.8 -54.7
TH_E DEV (C)       4     4     2     3     3     3     4     6     6     7     7     8     8
700-500 MB RH     73    68    68    63    63    56    50    46    45    40    40    41    40
GFS VTEX (KT)     12    11    14    12    11    11     9     9     9     7     7     6     5
850 MB ENV VOR    24    26    26    20    25    27     2   -22   -45   -88  -130  -163  -179
200 MB DIV        49    83    64    42    21    42     4   -17    -2     2    -3   -34   -11
LAND (KM)        265   451   640   841  1015  1355  1709  2003  2272  2502  2390  2278  2296
LAT (DEG N)     15.4  16.4  17.3  18.0  18.7  20.2  21.6  22.9  24.2  25.6  26.9  27.8  27.6
LONG(DEG W)     19.9  21.4  22.9  24.7  26.4  30.0  33.5  36.4  39.0  41.2  42.6  43.1  43.2
STM SPEED (KT)    14    17    18    18    18    18    16    14    13    11     7     2     1
HEAT CONTENT       0     0     0     0     0     0     0     0     0     4     6     5     6

  FORECAST TRACK FROM BAMM      INITIAL HEADING/SPEED (DEG/KT):305/ 10      CX,CY:  -7/  6
  T-12 MAX WIND:  20            PRESSURE OF STEERING LEVEL (MB):  588  (MEAN=625)
  GOES IR BRIGHTNESS TEMP. STD DEV. 100-300 KM RAD: -99.0 (MEAN=20.0)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD: -99.0 (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.  -1.  -1.   2.   7.  11.  15.  17.  18.  20.
  VERTICAL SHEAR         1.   2.   3.   4.   5.   5.   3.   0.  -3.  -5.  -5.  -6.
  PERSISTENCE            1.   2.   2.   3.   3.   3.   3.   2.   2.   2.   1.   0.
  200/250 MB TEMP.       0.   0.   0.   0.   0.   0.   0.   0.   0.   1.   2.   3.
  THETA_E EXCESS         0.  -1.  -2.  -3.  -4.  -5.  -7.  -9. -10. -12. -12. -13.
  700-500 MB RH          0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  GFS VORTEX TENDENCY    0.   0.   0.  -1.  -1.  -3.  -3.  -3.  -5.  -5.  -7.  -7.
  850 MB ENV VORTICITY   0.   0.   0.   0.   0.   0.  -1.  -1.  -3.  -4.  -6.  -8.
  200 MB DIVERGENCE      0.   1.   1.   1.   2.   2.   1.   1.   0.   0.  -1.  -2.
  ZONAL STORM MOTION     0.   0.   0.   0.   1.   1.   1.   1.   1.   1.   1.   1.
  STEERING LEVEL PRES    0.   0.   0.   0.   0.   1.   0.   1.   1.   1.   0.   0.
  DAYS FROM CLIM. PEAK   0.   0.   0.  -1.  -1.  -1.  -2.  -2.  -2.  -2.  -2.  -3.
                        ----------------------------------------------------------
  SUB-TOTAL CHANGE       2.   5.   6.   7.  10.  11.  11.  11.   7.   4.   0.  -2.

  SATELLITE ADJUSTMENTS ----------------------------------------------------------
  MEAN ADJUSTMENT        0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  GOES IR STD DEV        0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  GOES IR PIXEL COUNT    0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
  OCEAN HEAT CONTENT     0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
                        ----------------------------------------------------------
  TOTAL ADJUSTMENT       0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.   0.
                        ----------------------------------------------------------
  TOTAL CHANGE (KT)      2.   5.   6.   7.  10.  11.  11.  11.   7.   4.   0.  -2.

   ** 2008 ATLANTIC RI INDEX AL982008     INVEST 07/30/08  12 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) :  12.7 Range: 35.1 to   3.2 Scaled/Wgted Val:  0.7/  1.1
 D200 (10**7s-1)       :  51.8 Range:-20.0 to 149.0 Scaled/Wgted Val:  0.4/  0.6
 POT = MPI-VMAX (KT)   :  76.0 Range: 25.1 to 130.7 Scaled/Wgted Val:  0.5/  0.6
 850-700 MB REL HUM (%):  71.0 Range: 56.0 to  88.0 Scaled/Wgted Val:  0.5/  0.2
 % area w/pixels <-30 C:9999.0 Range: 17.0 to 100.0 Scaled/Wgted Val:999.0/999.0
 STD DEV OF IR BR TEMP : 999.9 Range: 35.1 to   3.2 Scaled/Wgted Val:999.0/999.0
 Heat content (KJ/cm2) :   0.0 Range:  0.0 to 132.0 Scaled/Wgted Val:  0.0/  0.0
 
 Prob of RI for 25 kt RI threshold=   999% is 999.0 times the sample mean(12.3%)
 Prob of RI for 30 kt RI threshold=   999% is 999.0 times the sample mean( 7.8%)
 Prob of RI for 35 kt RI threshold=   999% is 999.0 times the sample mean( 4.5%)


Ignore the RI index, it does not have OHC input and hence is not working right.

[O Town]

LINK And click on storm 98

[njweather]

The 06Z GFS strengthens it for the next 24 hours, and moves it WNW for 72 hours, then moves it almost due W straight into the Leeward islands.

Perhaps it's detecting some kind of steering mechanism that would prevent a recurve.

[gatorcane]

TAFB estimate showing a more westerly track, ableit a weaker 98L:

[Blown Away]

Interesting 98L is at about 16N/42W, that would be almost due W from where it is now.

[Meso]

Here is where the GFS has the system (weak) in a few days

[wxman57]

The 06Z GFS strengthens it for the next 24 hours, and moves it WNW for 72 hours, then moves it almost due W straight into the Leeward islands.

Perhaps it's detecting some kind of steering mechanism that would prevent a recurve.

You need to track the 850mb vorticity on the 06Z GFS. That run keeps the vorticity center well NE of the Caribbean, crossing 20N near 55W then turning NW-N and out to sea. The reason for the west movement is the position of the high center to its north centered along 35W. It can't turn north into the high, has to move past the high then turn north. That turn comes after 50W. But it probably won't last that long.

12Z GFS moves the vorticity center north of 20N between 40W-45W then turns it off to the north and out to sea.

[Blown Away]

GFS goes W until @50W then goes NW out to sea.

http://www.wunderground.com/tropical/tr ... model.html

[Aric Dunn]

[gatorcane]

GFS shows the wave axis long 98L currently impacting the Leewards in 96 hours. You can see the "bump in the isobars near the Leewards." Although the GFS does not develop 98L (yet) I do think we need to closely watch it and given that 98L is going to stay weak for at least the next 3-4 days, should allow it to get very close or go through Leeward islands (and did I mention its August tomorrow?)

Unlike 97L which traversed a similar lattitude but recurved out to see before 50W, this invest is going to have strong subtropical ridging to the north (provided by an Azores High that is building west in tandem with 98Ls movement) and will keep it from recurving anytime soon.

[Ed Mahmoud]

Until a well developed system organizes, I like 850 mb vorticity. Isobars in the tropics harder to see. IMHO.


850 vort max moves WNW, passing safely North of the islands, and loses intensity.

(Same FSU web site, different menu item).