Effects of Synoptic Surveillance on model forecasts for
19 September 2005 0600 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 15 62112144195124127150167246
AVNO 10 56132193217195183160155189
%IMP33%10%-19%-34%-11%-57%-44%-7% 7%23%
GFNO 52114144183200133101 70 96149
GFDL 62149181207243183147131148173
%IMP-19%-31%-26%-13%-22%-38%-46%-87%-34%-16%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-33-32-59-83-117-126-93-81-77-62
AVNO-34-31-58-82-115-123-90-79-72-60
%IMP-3% 3% 2% 1% 2% 2% 3% 3% 6% 3%
GFNO 18 50 38 7-30-50-27-16-27-33
GFDL 13 48 43 4-34-51-24-19-21-36
%IMP28% 4%-13%43%-13%-2%11%-19%22%-9%

Landfall forecasts

24/0730 UTC 29.7N 93.7W between Johnson's Bayou, LA, and Sabine Pass 121.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNNNo landfall forecast
AVNONo landfall forecast
%IMP
GFNO29.5792.33114.5133.1Pecan Island, LA
GFDL29.6491.94113.0170.0Cheniere Au Tigre, LA
%IMP -21% -28%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 19 September 2005 0600 UTC (Tropical Storm 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 19 September 2005 0600 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 19 September 2005 0600 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 19 September 2005 0600 UTC.