Effects of Synoptic Surveillance on model forecasts for
07 July 2005 1200 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
AVNN 31126100 70 51 83173114 212 269
AVNO 69224150167170213200214 270 380
%IMP-123%-78%-50%-139%-233%-157%-16%-88% -27% -41%
GFNO 24 67 56 59 89 89 38 58 81 148
GFDL 74146144200243301282352407 442
%IMP-208%-118%-157%-239%-173%-238%-642%-507%-402%-199%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-79-77-60-36-69-70 4 -1 -3 -3
AVNO-80-77-52-31-60-66-21-10 -9 -4
%IMP-1% 0%13%14%13% 6%-425%-900%-200%-33%
GFNO-19-31 -7 13-11-25 7 -5 1 -1
GFDL-21-41 -9 19-20-46-10 -6 0 2
%imp-11%-32%-29%-46%-81%-76%-43%-20%100%-100%

Landfall forecasts

08/0245 UTC 19.9N 77.6W Punta del Ingles, Cuba, 14.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 19.8077.68 14.5 13.9Near Niquero, Granma, Cuba
AVNO20.0477.60 12.5 15.6Niquero, Granma, Cuba
%IMP-800% -12%
GFNO19.8477.69 14.0 11.5Near Niquero, Granma, Cuba
GFDL19.9077.30 11.5 31.3Niquero, Granma, Cuba
%IMP-333%-172%
08/1845 UTC 22.1N 80.7W just west of Punta Mangles Altos, Cuba, 30.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 21.6078.84 22.0199.7Colorado, Ciego de Avila, Cuba
AVNO21.5778.65 18.0219.5Ciego Corojo, Ciego de Avila, Cuba
%IMP -46% -10%
GFNO21.7379.23 22.0157.0Near Sancti Spiritus, Sancti Spiritus, Cuba
GFDL21.6179.07 20.5176.7Near Ciego de Avila, Ciego de Avila, Cuba
%IMP -17% -13%
10/1930 UTC 30.4N 87.1W Santa Rosa Island, FL, 79.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 30.3487.43 85.5 32.3Pensacola, FL
AVNO29.7984.77 71.5234.0Apalachicola, FL
%IMP -33%-624%
GFNO30.5487.08 78.0 15.8Pensacola, FL
GFDL29.7084.74 66.5239.9Apalachicola, FL
%IMP-833%-1418%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 07 July 2005 1200 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 07 July 2005 1200 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 07 July 2005 1200 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 07 July 2005 1200 UTC.