Effects of Synoptic Surveillance on model forecasts for
30 August 2006 0600 UTC
Ernesto.


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 32 40 85127135213382310122169
AVNO 30 45 72 91 99145143 71 71134
%IMP 6%-13%15%28%27%32%63%77%42%21%
GFNO 24 33 86141249499658627479412
GFDL 10 22 72157270546717713557402
%IMP58%33%16%-11%-8%-9%-9%-14%-16% 2%
AVNN -4-12-25-15 -6-20-21-10 -8-15
AVNO -1-12-26-16 -1-16-19 -4 -9-13
%IMP75% 0%-4%-7%83%20%10%40%-13%13%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
GFNO 15 5 -5 -6-12 9 -4 2 -6 -8
GFDL 15 13 13 -4-11 15 2 9 1 -7
%IMP 0%-160%-160%33% 8%-67%50%-350%83%13%

Landfall forecasts

01/0340 UTC 33.9N 78.1W Oak Island, NC, 45.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 32.7979.80 40.5200.3Isle of Palms, SC
AVNO 33.0579.52 40.0162.0Bull Bay, SC
%IMP -10% 19%
GFNO 32.9679.52 37.5168.1Bull Bay, SC
GFDL 32.7979.71 38.0193.7Isle of Palms, SC
%IMP6% -15%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 30 August 2006 0600 UTC (Tropical Storm Ernesto).

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 30 August 2006 0600 UTC.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 30 August 2006 0600 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 30 August 2006 0600 UTC.