Effects of Synoptic Surveillance on model forecasts for
11 August 2004 0000 UTC
Bonnie.
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 | 104 | 193 | | | |
| AVNO | 78 | 190 | | | | | |
| %IMP | 25% | 2% | | | | | |
|
| GFNO | 15 | 70 | 136 | 334 | 410 |
| GFDL | 33 | 77 | 136 | 335 | 480 |
| %IMP | -120% | -10% | 0% | 0% | -17% |
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -30 | -37 | | | | | |
| AVNO | -27 | -35 | | | | | |
| %IMP | 10% | 5% | | | | | |
|
| GFNO | -2 | 1 | 28 | 32 | 20 |
| GFDL | -1 | -2 | 40 | 20 | 17 |
| %IMP | 50% | -100% | -43% | 37% | 15% |
| | ||||||||||
| 12/1400 UTC 29.6N 85.1W St. Vincent/St. George Is., FL 38.0 h into the forecast | |||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 29.10 | 89.05 | 27.0 | 386.5 | Port Eads, LA
| %IMP
|
| GFNO | 30.31 | 86.02 | 43.0 | 118.6 | Inlet Beach, FL
| GFDL | 30.25 | 86.12 | 42.5 | 121.9 | Seagrove Beach, FL
| %IMP | 10% | -3%
| | ||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 11 August 2004 0000 UTC (Tropical Storm Bonnie).
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 11 August 2004 0000 UTC.
Figure 3. Ensemble perturbation variance at the nominal sampling time 11 August 2004 0000 UTC from the previous day NCEP ensemble forecast. The circles represent the dropwindsonde locations.
Figure 4. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 11 August 2004 0000 UTC. The circles represent the dropwindsonde locations.
