Effects of Synoptic Surveillance on model forecasts for
16 September 2000 0600 UTC
GORDON.


QuickTime movie of DLM wind model forecasts
QuickTime movie of DLM wind data increments


TRACK AND INTENSITY PERFORMANCE

TRACK (km)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN52.134.217.294.400.571.639.535.9999.9999.
AVAL74.171.226.333.478.705.851.815.9999.9999.
%IMP-42%-28%-4%-13%-20%-30%-33%-52%
GFNOdissipated
GFAL
%IMP
VBNO83.122.102.39.160.331.568.786.851.894.
VBAL94.132.126.44.124.264.480.702.784.859.
%IMP-13%-8%-24%-13%23%20%15%11%8%4%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-15.-30.-21.6.8.-7.-11.1.9999.9999.
AVAL-23.-32.-22.-1.7.-1.-12.-9.9999.9999.
%IMP-53%-7%-5%83%13%86%-9%-800%
GFNOdissipated
GFAL
%IMP
SHNO1.-5.1.25.38.41.32.28.19.17.
SHAL1.-5.1.25.38.40.31.27.18.16.
%IMP0%0%0%0%0%2%3%4%5%6%
DSNO1.-5.1.25.38.41.32.28.19.17.
DSAL1.-5.1.25.38.40.31.27.18.16.
%IMP0%0%0%0%0%2%3%4%5%6%

Landfall forecasts

18/0300 UTC 29.3N 83.2W near Cedar Key, FL 45 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN30.2585.6056.0254.4 Lynn Haven, FL
AVAL30.2085.9060.0279.0 Panama City Beach, FL
%IMP-36%-10%
GFNOdissipated
GFAL
%IMP
VBNO29.2383.0245.519.1 Cedar Key, FL
VBAL29.1682.9546.528.8 Cedar Key, FL
%IMP-200%-51%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 16 September 2000 0600 UTC (Tropical Storm Gordon).

Figure 2. Track forecasts for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the AVN, GFDL, and VBAR models initialized on 16 September 2000 0600 UTC. The best track is shown in black.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 16 September 2000 0600 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 16 September 2000 0600 UTC.