Effects of Synoptic Surveillance on model forecasts for
10 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
AVNN 91101116126247308351262251
AVNO 67119129175230253334203207
%IMP26%-18%-11%-39% 7%18% 5%23%18%
GFNO 69130209328466534648713806876
GFDL 491372143394715546687758811002
%IMP29%-5%-2%-3%-1%-4%-3%-9%-9%-14%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-75 -3 -5 -3 -2 -4 -5 -2 -3
AVNO-64 -7 -3 -3 0 -3 -3 0 -2
%IMP15%-133%40% 0%100%25%40%100%33%
GFNO -6 36 0 2 0 4 3 19 9 16
GFDL 0 41 -1 3 0 6 7 18 9 16
%imp100%-14%und%-50% 0%-50%-133% 5% 0% 0%

Landfall forecasts

10/1930 UTC 30.4N 87.1W Santa Rosa Island, FL, 19.5 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 30.3388.20 21.5105.7Dauphin Island, AL
AVNO30.2488.14 19.0101.3Dauphin Island, AL
%IMP 75% 4%
GFNO30.2388.31 21.0117.6Dauphin Island, AL
GFDL30.3088.44 22.0129.0Pascagoula, MS
%IMP -67% -10%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 10 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 10 July 2005 0000 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 10 July 2005 0000 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 10 July 2005 0000 UTC.