Effects of Synoptic Surveillance on model forecasts for
30 August 2004 0600 UTC
Frances.
Quicktime movie of AVN DLM wind model
forecast
Quicktime movie of DLM wind data
increment
| TRACK (km) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | 61 | 114 | 104 | 24 | 47 | 65 | 126 | 135 | 140 | 86
| AVNO | 24 | 25 | 25 | 62 | 73 | 108 | 136 | 167 | 198 | 118
| %IMP | 61% | 78% | 76% | -158% | -55% | -66% | -8% | -23% | -41% | -37%
|
| GFNO | 24 | 71 | 86 | 106 | 124 | 123 | 132 | 148 | 165 | 266
| GFDL | 21 | 35 | 33 | 35 | 15 | 24 | 39 | 78 | 134 | 235
| %IMP | 12% | 51% | 62% | 67% | 88% | 80% | 70% | 47% | 19% | 12%
|
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -75 | -73 | -84 | -79 | -75 | -79 | -68 | -53 | -43 | -34
| AVNO | -71 | -70 | -79 | -77 | -75 | -81 | -71 | -56 | -48 | -35
| %IMP | 5% | 4% | 6% | 3% | 0% | -3% | -4% | -6% | -12% | -3%
|
| GFNO | 2 | -5 | -6 | -13 | -20 | -27 | -19 | -11 | -11 | 1
| GFDL | -1 | 3 | -4 | -10 | -15 | -31 | -22 | -16 | -9 | 5
| %IMP | 50% | 40% | 33% | 23% | 25% | -15% | -16% | -45% | 18% | -400%
|
| | ||||||||||
| 02/1930 UTC 24.0N 74.5W San Salvador Island, Bahamas 85.5 h into the forecast | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 24.76 | 74.00 | 92.5 | 98.4 | Well offshore San Salvador Island, Bahamas
| AVNO | 24.76 | 73.75 | 92.0 | 113.5 | Well offshore San Salvador Island, Bahamas
| %IMP | 7% | -15%
|
| GFNO | 23.71 | 75.31 | 82.0 | 88.4 | Northern tip of Cat Island, Bahamas
| GFDL | 24.26 | 74.29 | 85.5 | 35.0 | San Salvador Island, Bahamas
| %IMP | 100% | 60%
|
|
03/0530 UTC 24.6N 75.6W Northern end of Cat Island, Bahamas 95.5 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | No landfall forecast
| %IMP
|
| GFNO | 23.95 | 75.67 | 84.5 | 72.6 | Southern tip of Cat Island, Bahamas
| GFDL | 25.06 | 75.23 | 93.5 | 63.3 | Near Northern tip of Cat Island, Bahamas
| %IMP | 82% | -13%
|
|
03/1000 UTC 25.1N 76.1W Eleuthera Island, Bahamas 100.0 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | No landfall forecast
| %IMP | |
|
| GFNO | 24.48 | 76.38 | 90.0 | 74.4 | Southern tip of Eleuthera Island, Bahamas
| GFDL | 25.52 | 75.73 | 97.0 | 59.7 | Near Central Eleuthera Island, Bahama
| %IMP | 70% | 20%
|
|
04/1000 UTC 26.6N 78.2W Grand Bahama Island, Bahamas 124.0 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | No landfall forecast
| %IMP | |
|
| GFNO | 26.50 | 78.60 | 108.0 | 41.3 | Grand Bahama Island, Bahamas
| GFDL | No landfall forecast
| %IMP | |
|
|
05/0430 UTC 27.2N 80.2W South end of Hutchinson Island, FL 142.5 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | No landfall forecast
| %IMP | |
|
| GFNO | No landfall forecast
| GFDL | No landfall forecast
| %IMP | |
|
|
06/1800 UTC 30.1N 84.0W Mouth of Aucilla River, FL 180.0 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | No landfall forecast
| %IMP | |
|
| GFNO | No landfall forecast
| GFDL | No landfall forecast
| %IMP | |
| | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 30 August 2004 0600 UTC (Hurricane Frances).
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 2004 0600 UTC.
Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 30 August 2004 0600 UTC.
