Effects of Synoptic Surveillance on model forecasts for
18 July 2005 0000 UTC
Emily.


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 80106 70 56 30 23153
AVNO 39 84 70 59153358405
%IMP51%21% 0%-5%-410%-1457%-165%
GFNO 35 49 70 98142290
GFDL 21 23 24 63142283
%IMP40%53%66%36% 0% 2%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-27-39-44-76-76-21-10
AVNO-11-18-16-46-61-27 -8
%IMP59%54%64%39%20%-29%20%
GFNO 23 21 15-11-31 -2
GFDL 25 25 18-11-26 0
%IMP-9%-19%-20% 0%16%100%

Landfall forecasts

18/0630 UTC 20.3N 87.4W Near Tulum, Mexico, 6.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 20.2287.36 4.5 9.8Zamach, Qintana Roo, Mexico
AVNO20.3187.43 5.5 3.3Cozumel, Qintana Roo, Mexico
%IMP 50% 66%
GFNO20.2587.38 5.5 5.9Tulum, Qintana Roo, Mexico
GFDL20.4887.22 5.5 27.4Playa del Carmen, Qintana Roo, Mexico
%IMP 0%-364%
20/1200 UTC 24.8N 97.6W Near San Fernando, Mexico, 60.0 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 24.6997.65 61.5 13.2La Coyota, Tamaulipas, Mexico
AVNO23.6697.79 58.5128.1Morales, Tamaulipas, Mexico
%IMP 0%-870%
GFNO23.8197.75 55.5111.0La Pesca, Tamaulipas, Mexico
GFDL23.9797.78 55.5 94.0Soto la Marina, Tamaulipas, Mexico
%IMP 0% 15%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 18 July 2005 0000 UTC (Hurricane Emily).

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 18 July 2005 0000 UTC.

Figure 3. NCEP Global Ensemble Prediction System track forecasts for all cyclones in the Atlantic basin initialized from 16 July 2005 0600 UTC to 17 July 2005 0000 UTC, showing the tracks of Hurricane Emily.

Figure 4. Ensemble perturbation variance at the nominal sampling time 18 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 18 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 18 July 2005 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 7. NOGAPS Singular Vector for observations taken at the sampling time 18 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 18 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 18 July 2005 0000 UTC.