Effects of Synoptic Surveillance on model forecasts for
11 September 2005 0000 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 35105157217273299256243299513
AVNO 44 9 83136166198213275390584
%IMP-26%91%47%36%39%34%17%-13%-30%-14%
GFNO 11 31 28 67 79 57 58192339556
GFDL 11 15 29 61 74 93147290492869
%IMP 0%52%-4% 9% 6%-63%-153%-51%-45%-56%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-14 5 5 4 6 0 -1 -4 -3 4
AVNO -7 -1 12 -2 6 3 -6-14-13-15
%IMP50%80%-140%50% 0%ud3%-500%-250%-333%-275%
GFNO 3 8 7 9 4 6-13-20-14-14
GFDL 7 7 0 0 5 3 -9-19-15-13
%IMP-133%12%100%100%-25%50%31% 5%-7% 7%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 11 September 2005 0000 UTC (Hurricane 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 11 September 2005 0000 UTC.

Figure 3. NCEP Global Ensemble Prediction System track forecasts for all cyclones in the Atlantic basin initialized from 09 September 2005 0600 UTC to 10 September 2005 0000 UTC, showing the tracks of Hurricane Ophelia.

Figure 4. Ensemble perturbation variance at the nominal sampling time 11 September 2005 0000 UTC from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.

Figure 5. Variance explained within the verification region (large red circle) for observations taken at the sampling time 11 September 2005 0000 UTC from the Ensemble Transform Kalman Filter run from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.

Figure 6. Adjoint-Derived Steering Sensitivity Vector for observations taken at the sampling time 11 September 2005 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 7. NOGAPS Singular Vector for observations taken at the sampling time 11 September 2005 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 8. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 11 September 2005 0000 UTC. The circles represent the dropwindsonde locations.

Figure 9. 24-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 11 September 2005 0000 UTC.