Effects of Synoptic Surveillance on model forecasts for
11 June 2005 0600 UTC
Arlene.



TRACK AND INTENSITY PERFORMANCE

TRACK (km)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN 49183303448
AVNO 40 35167160
%IMP18%81%45%65%
GFNO 82207421519372560
GFDL 53182401487345477
%IMP35%12% 5% 6% 7%15%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-28 -7 -9-11
AVNO-17 -7 -6 -8
%IMP39% 0%33%27%
GFNO 6 13 1 4 14 24
GFDL 7 15 3 -6 14 29
%IMP-17% -15%-200%-50% 0%-21%

Landfall forecasts

11/1900 UTC 30.3N 87.5W Near and just west of Pensacola 13.0 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 30.2588.15 15.5 62.6Dauphin Island, AL
AVNO30.3787.21 14.0 28.9Pensacola, FL
%IMP 60% 54%
GFNO30.3888.57 18.5103.0Pascagoula, MS
GFDL30.3488.18 17.0 65.4Dauphin Island, AL
%IMP 27% 37%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 11 June 2005 0600 UTC (Tropical Storm Arlene).[Not Available]

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 11 June 2005 0600 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 11 June 2005 0600 UTC. [Not Available]

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 11 June 2005 0600 UTC. [Not Available]