Effects of Synoptic Surveillance on model forecasts for
07 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 | Lost center at 6 h
| AVNO | Lost center at 6 h
| %IMP |
|
| GFNO | 71 | 79 | 62 | 15 | 54 | 131 | 182 | 224 | 301 | 370
| GFDL | 55 | 78 | 102 | 46 | 87 | 151 | 220 | 263 | 293 | 337
| %IMP | 23% | 1% | -71% | -207% | -61% | -15% | -27% | -15% | 3% | 9%
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | Lost center at 6 h
| AVNO | Lost center at 6 h
| %IMP |
|
| GFNO | 8 | -5 | -10 | -29 | -10 | -11 | -8 | -21 | -40 | -27
| GFDL | -9 | -18 | -24 | -36 | -19 | -14 | -12 | -20 | -45 | -49
| %IMP | -13% | -260% | -140% | -24% | -90% | -27% | -50% | 5% | -13% -18%
| | ||||||||||||||||||||||||||||||||||||||||||||||
| 07/2130 UTC 11.9N 61.8W 6 n mi SW of Prickly Point, Grenada 15.5 h into the forecast | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 12.06 | 61.75 | 14.5 | 18.6 | St. George's, Grenada
| %IMP |
|
| GFNO | 11.55 | 61.95 | 17.5 | 42.2 | Near St. George's, Grenada
| GFDL | 11.45 | 61.74 | 15.5 | 50.4 | Near St. George's, Grenada
| %IMP | 100% | -19%
|
|
11/0330 UTC 17.4N 77.2W 20 n mi S of Portland Point, Jamaica 93.5 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 17.93 | 76.68 | 94.5 | 80.6 | August Town, Jamaica
| %IMP |
|
| GFNO | 17.36 | 77.30 | 83.5 | 11.5 | Offshore Old Harbour, Jamaica
| GFDL | No landfall forecast
| %IMP |
|
|
12/1415 UTC 18.9N 81.5W 22 n mi SSW of Georgetown, Grand Cayman Island 128.25 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 18.43 | 77.01 | 98.5 | 475.5 | Ocho Rios, Jamaica
| %IMP | |
|
| GFNO | 18.85 | 81.52 | 107.0 | 5.9 | Offshore Georgetown, Grand Cayman Island
| GFDL | No landfall forecast
| %IMP |
|
|
14/0100 UTC 21.7N 85.2W 15 n mi SW of Cabo San Antonio, Cuba 163.0 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 21.56 | 79.31 | 118.5 | 609.5 | Near Sancti Spiritus, Sancti Spiritus, Cuba
| %IMP | |
|
| GFNO | No landfall forecast
| GFDL | No landfall forecast
| %IMP |
|
|
16/0650 UTC 30.2N 87.9W Near Pine Beach, AL 216.5 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 |
| | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 07 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 07 September 2004 0600 UTC.
Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 07 September 2004 0600 UTC.
