Effects of Synoptic Surveillance on model forecasts for
08 July 2005 0000 UTC
Dennis.


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
AVNN118 78 98 74 81 66 47127 76 138
AVNO133129 98111107 95 84130105 127
%IMP-13%-65% 0%-50%-32%-44%-79%-2%-38% 8%
GFNO 15 31 72 92131170222296434 517
GFDL 80 80 59102128101110 42 54 14
%IMP-433%-158%18%-11% 2%41%50%86%88% 98%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-85-63-40-70-76 -8 0 -5 -1 -1
AVNO-75-50-26-50-55 -7 -5 -6 -2 0
%IMP12%21%35%29%28%13%und%-20%-100%100%
GFNO -4 8 30 -4-16 19 -2 2 2 2
GFDL-26-10 28 -6-25 -5 -5 2 0 2
%imp-550%-25% 7%-50%56%84%-150% 0%100% 0%

Landfall forecasts

08/0245 UTC 19.9N 77.6W Punta del Ingles, Cuba, 2.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 19.7777.72 2.0 19.1Near Niquero, Granma, Cuba
AVNO20.0977.52 3.5 22.7Niquero, Granma, Cuba
%IMP 0% -19%
GFNO19.7877.82 3.0 26.6Near Niquero, Granma, Cuba
GFDL19.8777.46 2.5 15.0Niquero, Granma, Cuba
%IMP 0% 44%
08/1845 UTC 22.1N 80.7W just west of Punta Mangles Altos, Cuba, 18.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 21.6879.61 10.5121.7Banao, Sancti Spiritus, Cuba
AVNO21.6178.64 10.0219.3Ciego Corojo, Ciego de Avila, Cuba
%IMP -6% -80%
GFNO22.1381.14 20.0 45.4Aguada de Pasajeros, Cienfuegos, Cuba
GFDL21.5179.19 11.5169.0Near Ciego de Avila, Ciego de Avila, Cuba
%IMP-480%-272%
10/1930 UTC 30.4N 87.1W Santa Rosa Island, FL, 67.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 30.6288.06 69.5 95.1Mobile, AL
AVNO30.4586.14 67.5 92.1Santa Rosa Beach, FL
%IMP 100% 3%
GFNO30.1888.53 66.0139.3Pascagoula, MS
GFDL30.3987.13 63.5 3.1Pensacola, FL
%IMP-167% 98%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 08 July 2005 0000 UTC (Hurricane Dennis).

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 08 July 2005 0000 UTC.

Figure 3. NCEP Global Ensemble Prediction System track forecasts for all cyclones in the Atlantic basin initialized from 06 July 2005 0600 UTC to 07 July 2005 0000 UTC, showing the tracks of Hurricane Dennis.

Figure 4. Ensemble perturbation variance at the nominal sampling time 08 July 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 08 July 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 08 July 2005 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 7. NOGAPS Singular Vector for observations taken at the sampling time 08 July 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 08 July 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 08 July 2005 0000 UTC.