Effects of Synoptic Surveillance on model forecasts for
21 September 2005 1800 UTC
Rita.


Quicktime movie of AVN 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
AVNN 42 60 92121163211326503 967
AVNO 20 10 37 771492273626201170
%IMP52%83%60%36% 9%-8%-11%-23%-21%
GFNO 61101123150134193262458 880
GFDL 46 751041401412183365621099
%IMP25%26%15% 7%-5%-13%-28%-23%-25%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-106-76-60-54-32 7 1 -8 -2
AVNO -95-52-44-34-11 26 11 5 2
%IMP10%32%27%37%66%-271%-1000%37% 0%
GFNO-50-14 -5 -7 -3 16 -4 6 1
GFDL-44-20 -4 -8 -8 24 11 2 7
%IMP12%-43%20%-13%-167%-50%-175%33%-600%

Landfall forecasts

24/0730 UTC 29.7N 93.7W between Johnson's Bayou, LA, and Sabine Pass 61.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 29.2694.89 67.5125.0Galveston, TX
AVNO29.4894.57 71.0 87.5Galveston, TX
%IMP -58% 30%
GFNO29.2195.05 62.5141.5Galveston, TX
GFDL29.1695.02 65.0141.1Galveston, TX
%IMP-250% 0%

Figure 1. NCEP 850 - 210 hPa mean wind analysis for 21 September 2005 1800 UTC (Hurricane Rita).

Figure 2. Track forecasts for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the AVN and GFDL models initialized on 21 September 2005 1800 UTC.

Figure 3. Initial condition differences in the 850 - 210 hPa mean wind between the no and all dropwindsonde cases for 21 September 2005 1800 UTC.

Figure 4. 12-h forecast differences in the 850 - 210 hPa mean wind between the no and all dropwindsonde cases for 21 September 2005 1800 UTC.