Effects of Synoptic Surveillance on model forecasts for
13 September 2005 1800 UTC
Ophelia.


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 22 76 86144185236404359357404
AVNO 29 72 78149183202297223334492
%IMP32% 5%-9%-3% 1%14%26%38% 6%-22%
GFNO 52 72 56 45154227308323355411
GFDL 29 43 49 65114143188152176297
%IMP44%40%32%-44%26%27%39%53%50%28%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-19-23-28-24-13-15 -9-11-11-13
AVNO-20-22-21-16-15-13 -1 -1 3 3
%IMP-5% 4%25%33%-15%13%89%91%73%77%
GFNO -8-17-14 -9 3 7 12 4 17 8
GFDL -1 -6 -8 -7 8 11 27 23 15 3
%IMP87%65%43%22%-167%-57%-125%-475%12%62%

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

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 September 2005 1800 UTC.

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

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