Effects of Synoptic Surveillance on model forecasts for
13 August 2005 1800 UTC
Irene.


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
AVNN1141301973265566288541030 863
AVNO 80124196318502686914 10341166
%IMP30% 5% 1% 2%10% -9% -7% 0% -35%
GFNONo forecast available
GFDLNo forecast available
%IMPNo forecast available
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-38-43-59-62-63-71 -55-43-37
AVNO-31-38-51-55-55-61-47-33-15
%IMP14%12%14%11%13%14%15%23%59%
GFNONo forecast available
GFDLNo forecast available
%IMPNo forecast available

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 13 August 2005 1800 UTC (Tropical Storm Irene).

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 13 August 2005 1800 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 13 August 2005 1800 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 13 August 2005 1800 UTC.