Effects of Synoptic Surveillance on model forecasts for
24 August 2000 0000 UTC
DEBBY.


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
AVNN178.
AVAL281.
%IMP-58
GFNOno verification
GFALno verification
%IMP
VBNO137.
VBAL129.
%IMP6%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-4.
AVAL-3.
%IMP25
GFNOno verification
GFALno verification
%IMP
SHNO1.
SHAL1.
%IMP0%
DSNO0.
DSAL0.
%IMP0%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 24 September 2000 0000 UTC (Tropical Storm Debby).

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 24 September 2000 0000 UTC. The best track is shown in black.

Figure 3. Ensemble perturbation variance at the nominal sampling time 24 September 2000 0000 UTC from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.

Figure 4. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 24 September 2000 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 5. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 24 September 2000 0000 UTC.