Effects of Synoptic Surveillance on model forecasts for
14 August 2005 0000 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
AVNN100124201
AVNO 56 93182
%IMP44%25% 9%
GFNO 14 29 21 57111178295442526
GFDL 22 38 33 24101193288402451
%IMP-57%-31%-57%58% 9% -8% 2% 9%14%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-38-51-59
AVNO-32-49-54
%IMP16% 4% 8%
GFNO -6-24-21 -6 1 2 9 15 9
GFDL 6-15 -6 4 5 8 17 12 2
%IMP 0%38%71%33%-400%-300%-89%20%78%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 14 August 2005 0000 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 14 August 2005 0000 UTC.

Figure 3. NCEP Global Ensemble Prediction System track forecasts for all cyclones in the Atlantic basin initialized from 12 August 2005 0600 UTC to 13 August 2005 0000 UTC, showing the tracks of Tropical Storm Irene.

Figure 4. Ensemble perturbation variance at the nominal sampling time 14 August 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 14 August 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 14 August 2005 0000 UTC. The green circles represent the dropwindsonde locations. [Not available]

Figure 7. NOGAPS Singular Vector for observations taken at the sampling time 14 August 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 14 August 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 14 August 2005 0000 UTC.