Effects of Synoptic Surveillance on model forecasts for
20 August 2000 1800 UTC
DEBBY.
QuickTime movie of DLM wind model forecasts
QuickTime movie of DLM wind data increments
| TRACK (km) | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | 123. | 226. | 252. | 263. | 317. | 298. | 224.
| AVAL | 85. | 124. | 141. | 197. | 313. | 327. | 261.
| %IMP | 31% | 45% | 44% | 25% | 1% | -10% | -17%
|
| GFNO | 96. | 59. | 39. | 124. | 119. | 181. | 396.
| GFAL | 122. | 122. | 245. | 284. | 329. | 263. | 179.
| %IMP | -27% | -107% | -528% | -129% | -176% | -45% | 55%
|
| VBNO | 153. | 302. | 331. | 466. | 529. | 684. | 869.
| VBAL | 143. | 273. | 297. | 441. | 504. | 664. | 857.
| %IMP | 7% | 10% | 10% | 5% | 5% | 3% | 1%
| 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. | -43. | -38. | -40. | -42. | -32. | -19.
| AVAL | -23. | -33. | -25. | -33. | -36. | -25. | -15.
| %IMP | 23% | 23% | 34% | 18% | 14% | 22% | 21%
|
| GFNO | -20. | -22. | -2. | 12. | 29. | 48. | 58.
| GFAL | -24. | -30. | -17. | -6. | 3. | 3. | 25.
| %IMP | -20% | -36% | -750% | 50% | 90% | 94% | 57%
|
| SHNO | -18. | -19. | -2. | 5. | 11. | 29. | 47.
| SHAL | -18. | -21. | -5. | 0. | 5. | 21. | 39.
| %IMP | 0% | -11% | -150% | 100% | 55% | 28% | 38%
|
| DSNO | -18. | -19. | -2. | 5. | 11. | 29. | 47.
| DSAL | -18. | -21. | -5. | 0. | 5. | 21. | 39.
| %IMP | 0% | -11% | -150% | 100% | 55% | 28% | 38%
| | ||||||||||
22/0600 UTC 17.5N 61.7W near Barbuda 36 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.05 | 61.08 | 30.0 | 89.6 | Near Barbuda
| AVAL | 17.65 | 61.73 | 32.5 | 17.0 | Near Barbuda
| %IMP | 42% | 81%
|
| GFNO | 17.18 | 61.75 | 35.5 | 35.9 | St. John's, Antigua
| GFAL | 16.40 | 61.30 | 29.0 | 129.4 | Ste.-Marguerite, Guadeloupe
| %IMP | -1300% | -260%
|
| VBNO | 18.37 | 61.85 | 52.5 | 97.9 | Near Barbuda
| VBAL | 18.06 | 61.78 | 50.5 | 62.8 | Near Barbuda
| %IMP | 12% | 36%
|
|
| 22/0915 UTC 17.9N 62.8W near St.-Barthelemy 39.25 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.05 | 63.10 | 33.5 | 35.8 | Marigot, St. Martin
| AVAL | 17.80 | 63.00 | 36.0 | 23.9 | Near St.-Barthelemy
| %IMP | 43% | 33%
|
| GFNO | 17.32 | 62.78 | 39.0 | 64.5 | Frigate Bay, St. Kitts
| GFAL | 16.56 | 65.09 | 40.5 | 285.0 | Near St. Croix
| %IMP | -400% | -497%
|
| VBNO | 18.40 | 63.02 | 59.0 | 60.2 | Near Anguilla
| VBAL | 18.17 | 63.15 | 58.0 | 47.6 | The Valley, Anguilla
| %IMP | 5% | 21%
|
|
| 22/1500 UTC 18.5N 64.4W near Virgin Gorda 45 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.22 | 64.87 | 38.5 | 58.5 | Near St. Thomas, British Virgin Islands
| AVAL | 18.12 | 65.34 | 42.5 | 107.8 | Vieques, Puerto Rico
| %IMP | 62% | -84%
|
| GFNO | 17.63 | 64.83 | 46.5 | 106.8 | Near St. Croix
| GFAL | 16.91 | 67.33 | 48.5 | 356.9 | Near Puerto Rico
| %IMP | -133% | -234%
|
| VBNO | 18.39 | 64.64 | 68.5 | 28.1 | Sea Cow Bay, Tortola
| VBAL | 18.36 | 65.03 | 69.5 | 68.2 | David Point, St. Thomas
| %IMP | -4% | -143%
| | |||||||||||||||||||||||||||||||||||||||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 20 August 2000 1800 UTC (Tropical Storm Debby).
Figure 2. Track forecasts for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the AVN, GFDL, and VBAR models initialized on 20 August 2000 1800 UTC. The best track is shown in black.
Figure 3. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 20 August 2000 1800 UTC.
