Effects of Synoptic Surveillance on model forecasts for
03 September 2004 1200 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 | 20 | 30 | 40 | 37 | 76 | 59 | 58 | 15 | 90 | 195
| AVNO | 30 | 32 | 23 | 23 | 29 | 31 | 35 | 58 | 244 | 317
| %IMP | -50% | -7% | 42% | 38% | 62% | 47% | 40% | -287% | -171% | -63%
|
| GFNO | 15 | 0 | 24 | 0 | 35 | 58 | 95 | 177 | 262 | 309
| GFDL | 23 | 10 | 37 | 35 | 0 | 31 | 119 | 163 | 231 | 285
| %IMP | -53% | und% | -54% | und% | 100% | 47% | -25% | 8% | 12% | 8%
|
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -33 | -35 | -24 | -14 | 4 | -10 | 4 | -1 | -1 | -2
| AVNO | -2 | -16 | -8 | -19 | 1 | -10 | 10 | -1 | 4 | 3
| %IMP | 94% | 54% | 67% | -36% | 75% | 0% | -60% | 0% | -300% | -50%
|
| GFNO | 25 | 22 | 18 | 17 | 27 | 10 | 22 | 21 | 13 | 20
| GFDL | 18 | 14 | 17 | 11 | 29 | 11 | 22 | 27 | 13 | 19
| %IMP | 28% | 36% | 6% | 35% | -7% | -10% | 0% | -29% | 0% | 5%
|
| | ||||||||||
| 04/1000 UTC 26.6N 78.2W Grand Bahama Island, Bahamas 22.0 h into the forecast | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 26.72 | 78.06 | 22.0 | 19.3 | Grand Bahama Island, Bahamas
| AVNO | 26.71 | 78.29 | 19.5 | 15.1 | Grand Bahama Island, Bahamas
| %IMP | und% | 22%
|
| GFNO | 26.62 | 78.18 | 20.5 | 13.5 | Grand Bahama Island, Bahamas
| GFDL | 26.65 | 78.16 | 20.0 | 6.8 | Grand Bahama Island, Bahamas
| %IMP | -33% | 50%
|
|
05/0430 UTC 27.2N 80.2W South end of Hutchinson Island, FL 40.5 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 27.61 | 80.34 | 46.5 | 48.6 | Fort Pierce, FL
| AVNO | 27.29 | 80.22 | 41.0 | 10.2 | Port St. Lucie, FL
| %IMP | 92% | 79%
|
| GFNO | 27.32 | 80.25 | 42.5 | 14.2 | Port St. Lucie, FL
| GFDL | 26.83 | 80.02 | 38.5 | 44.8 | Riviera Beach, FL
| %IMP | 0% | -215%
|
06/1800 UTC 30.1N 84.0W Mouth of Aucilla River, FL 78.0 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | No landfall forecast
| AVNO | 30.08 | 84.11 | 78.0 | 10.8 | St. Marks, FL
| %IMP | |
|
| GFNO | 29.84 | 84.71 | 75.0 | 74.2 | Carrabelle Beach, FL
| GFDL | 29.83 | 84.66 | 76.0 | 70.3 | Carrabelle Beach, FL
| %IMP | 33% | 5%
| | ||||||||||||||||||||||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 03 September 2004 1200 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 03 September 2004 1200 UTC.
Figure 3. NCEP Global Ensemble Predction System track forecasts for all cyclones in the Atlantic basin initialized from 01 september 2004 0600 UTC to 02 September 2004 1200 UTC, showing the tracks of Hurricane Frances.
Figure 4. Ensemble perturbation variance at the nominal sampling time 03 September 2004 1200 UTC from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.
Figure 5. Variance explained within the verification region (large red circle) for observations taken at the sampling time 03 September 2004 1200 UTC from the Ensemble Transform Kalman Filter run from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.
Figure 6. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 03 September 2004 1200 UTC. The circles represent the dropwindsonde locations.
