Effects of Synoptic Surveillance on model forecasts for
15 September 2004 0600 UTC
Ivan.
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 | 20 | 44 | 59 | 154 | 274 | 458 | 676 | 763 | 781 | 1090
| AVNO | 24 | 68 | 76 | 150 | 302 | 504 | 701 | 763 | 819 | 1088
| %IMP | -20% | -55% | -29% | 3% | -10% | -10% | -4% | 0% | -5% | 0%
|
| GFNO | 20 | 51 | 60 | 201 | 339 | 525 | 668 | 921 | 986 | 1226
| GFDL | 23 | 53 | 36 | 178 | 322 | 529 | 722 | 916 | 1014 | 1224
| %IMP | -15% | -4% | 40% | 11% | 5% | -1% | -8% | 1% | -3% | 0%
|
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -37 | -26 | -6 | -2 | -3 | 4 | -8 | -24 | -22 | -26
| AVNO | -36 | -23 | -2 | -2 | -2 | 5 | -9 | -25 | -22 | -26
| %IMP | 3% | 12% | 67% | 0% | 33% | -25% | -13% | -5% | 0% | 0%
|
| GFNO | -4 | 6 | 12 | 7 | 14 | 28 | 17 | 5 | -3 | -1
| GFDL | -2 | 2 | 11 | 7 | 14 | 27 | 17 | 2 | 1 | -7
| %IMP | 50% | 67% | 8% | 0% | 0% | 4% | 0% | 60% | 67% | -500%
|
| | ||||||||||
| 16/0650 UTC 30.2N 87.9W Near Pine Beach, AL 25.0 h into the forecast | |||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 30.25 | 87.72 | 26.0 | 18.2 | Gulf Shores, AL
| AVNO | 30.24 | 88.14 | 26.5 | 23.5 | Dauphin Island, AL
| %IMP | -50% | -29%
|
| GFNO | 30.39 | 88.18 | 26.0 | 34.2 | Dauphin Island, AL
| GFDL | 30.20 | 88.06 | 25.5 | 15.4 | Dauphin Island, AL
| %IMP | 50% | 55%
| | ||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 15 September 2004 0600 UTC (Hurricane Ivan).
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 15 September 2004 0600 UTC.
Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 15 September 2004 0600 UTC.
