Effects of Synoptic Surveillance on model forecasts for
29 August 2005 1200 UTC
Katrina.

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

TRACK AND INTENSITY PERFORMANCE
TRACK (km)
MODEL	12 h	24 h	36 h	48 h	60 h	72 h	84 h	96 h	108 h	120 h

AVNN	48	14	62
AVNO	28	24	14
%IMP	42%	-71%	77%

GFNO	73	35	34
GFDL	38	24	21
%IMP	48%	31%	38%
INTENSITY (kt)
MODEL	12 h	24 h	36 h	48 h	60 h	72 h	84 h	96 h	108 h	120 h

AVNN	-14	-10	-15
AVNO	-14	-9	-14
%IMP	0%	10%	7%

GFNO	1	-5	-4
GFDL	0	-6	-7
%IMP	100%	-20%	-75%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 29 August 2005 1200 UTC (Hurricane Katrina).

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 29 August 2005 1200 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 29 August 2005 1200 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 29 August 2005 1200 UTC.