Effects of Synoptic Surveillance on model forecasts for
19 October 1999 1800 UTC
JOSE.


QuickTime movie of DLM wind model forecasts
QuickTime movie of DLM wind data increments


TRACK AND INTENSITY PERFORMANCE

TRACK (km)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN112.85.57.67.140.235.334.583.
AVAL101.77.25.84.144.216.283.496.
%IMP10%9%56%-25%-3%8%15%15%
GFNO101.46.11.135.300.571.858.1414.1977.2063.
GFAL69.39.78.256.425.702.1021.1591.2051.2076.
%IMP32%15%-609%-90%-42%-23%-19%-13%-4%-1%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN-51.-51.-41.-29.-23.-22.-20.-21.
AVAL-46.-48.-36.-25.-18.-18.-14.-14.
%IMP10%6%12%14%22%18%30%33%
GFNO6.15.28.47.56.56.57.44.13.-10.
GFAL7.13.42.52.61.54.50.44.17.-3.
%IMP-17%13%50%-11%-9%4%12%0%-31%70%
SHNO-8.-2.17.31.38.38.40.36.33.28.
SHAL-8.-2.17.30.37.36.37.34.30.25.
%IMP0%0%0%3%3%5%8%6%9%11%
DSNO-8.-2.17.31.38.38.40.36.33.28.
DSAL-8.-2.17.30.37.36.37.34.30.25.
%IMP0%0%0%3%3%5%8%6%9%11%

Landfall forecasts

20/1600 UTC 17.1N 61.7W Antigua 22 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN16.7862.1519.059.6 Plymouth, Montserrat
AVAL17.1561.7017.05.6 Saint John's, Antigua
%IMP-67%91%
GFNO15.9961.2216.0133.5 Saint-Louis, Marie-Galante, Guadeloupe
GFAL16.9961.8420.519.2 Old Road, Antigua
%IMP75%86%
21/1105 UTC 18.4N 64.6W Tortola 41.08 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN18.3964.6740.07.5 Road Town, Tortola, British Virgin Islands
AVAL18.7064.2740.548.2 Anegada, British Virgin Islands
%IMP-49%-543%
GFNO18.6564.4339.533.0 Anegada, British Virgin Islands
GFAL18.0763.1230.5160.4 Marigot, St. Martin
%IMP-570%-386%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 19 October 1999 1800 UTC (Hurricane Jose).

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 19 October 1999 1800 UTC. The best track is shown in black.

Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 19 October 1999 1800 UTC.

Figure 4. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 19 October 1999 1800 UTC.