Effects of Synoptic Surveillance on model forecasts for
14 July 2003 1800 UTC
Claudette.


Quicktime movie of GFS DLM wind model forecast
Quicktime movie of DLM wind data increment


TRACK AND INTENSITY PERFORMANCE

TRACK (km)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
GFSN 94190171294365
GFSO 69170180295446
%IMP27%11%-5% 0%-22%
GFNO 52104 96193281
GFDL 24 69 49133197
%IMP54% 34%49%31%30%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
GFSN-39-47-17-22-15
GFSO-32-42-15-20-13
%IMP18%11%12% 9%13%
GFNO 9 17 16 7 24
GFDL 6 8 12 11 16
%IMP33%53%25%-57%33%
SHNO-10-12 19 26 37
SHIP -9-12 19 25 35
%IMP10% 0% 0% 4% 4%
DSNO-10-12 -1 -4 3
DSHP -9 -12 0 -4 3
%IMP10% 0%100% 0% 0%

Landfall forecasts

15/1530 UTC 28.3N 96.2W Matagorda Island, TX 21.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
GFSN27.1497.4031.0174.8La Parra Landing, TX
GFSO27.1397.4133.0176.2La Parra Landing, TX
%IMP-21% -1%
GFNO27.9496.9928.0 87.1Port Aransas, TX
GFDL28.0196.9025.0 75.8Rockport, TX
%IMP 46% 13%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 14 July 2003 1800 UTC (Tropical Storm Claudette).

Figure 2. Track forecasts for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models initialized on 14 July 2003 1800 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 14 July 2003 1800 UTC.

Figure 4. 14-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 14 July 2003 1800 UTC.