Effects of Synoptic Surveillance on model forecasts for
16 November 1999 0000 UTC
LENNY.
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 | 237. | 266. | 308. | 332. | 279. | 221. | 231. | 423. | 591. | 757.
| AVAL | 87. | 96. | 125. | 21. | 84. | 290. | 534. | 785. | 950. | 1062.
| %IMP | 73% | 64% | 59% | 94% | 70% | -31% | -130% | -86% | -61% | -40%
|
| GFNO | 107. | 177. | 193. | 134. | 202. | 457. | 730. | 985. | 1208. | 1418.
| GFAL | 78. | 118. | 139. | 118. | 201. | 442. | 724. | 957. | 1157. | 1385.
| %IMP | 27% | 33% | 28% | 12% | 0% | 3% | 4% | 3% | 1% | 2%
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -47. | -62. | -80. | -99. | -92. | -57. | -42. | -18. | -11. | -8.
| AVAL | -44. | -61. | -80. | -96. | -90. | -57. | -43. | -26. | -11. | 0.
| %IMP | 6% | 2% | 0% | 3% | 2% | 0% | -2% | -44% | 0% | 100%
|
| GFNO | 20. | 6. | -3. | -20. | -14. | 16. | 28. | 36. | 52. | 66.
| GFAL | 21. | 10. | -3. | -18. | -16. | 15. | 25. | 34. | 52. | 66.
| %IMP | -5% | -67% | 0% | 10% | 14% | 6% | 11% | 6% | 0% | 0%
|
| SHNO | -9. | -22. | -37. | -56. | -48. | -24. | -12. | 0. | 1. | 7.
| SHAL | -10. | -25. | -41. | -59. | -51. | -26. | -13. | -1. | 2. | 8.
| %IMP | -11% | -14% | -11% | -5% | -6% | -8% | -8% | und% | -100% | -14%
|
| DSNO | -9. | -22. | -49. | -70. | -62. | -38. | -26. | -15. | -13. | -7.
| DSAL | -10. | -25. | -52. | -72. | -64. | -39. | -26. | -14. | -12. | -5.
| %IMP | -11% | -14% | -6% | -3% | -3% | -3% | 0% | 7% | 8% | 29%
| | ||||||||||
| 17/1800 UTC 17.4N 64.8W St. Croix, USVI 42 h into the forecast | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.13 | 65.52 | 67.5 | 111.3 | Barreada Monte Santo, Vieques, PR
| AVAL | 17.56 | 64.48 | 47.5 | 38.3 | Christiansted, St. Croix, USVI
| %IMP | 78% | 66%
|
| GFNO | 18.07 | 65.46 | 47.0 | 102.1 | Barreada Monte Santo, Vieques, PR
| GFAL | 17.90 | 65.83 | 41.5 | 122.4 | Garona, PR
| %IMP | 90% | -20%
|
|
18/1800 UTC 18.0N 63.3W St. Martin 66 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 19.10 | 64.68 | 76.0 | 189.9 | Near Anegada, British Virgin Islands
| AVAL | 18.32 | 63.13 | 59.0 | 39.8 | The Valley, Anguilla
| %IMP | 30% | 79%
|
| GFNO | 18.39 | 65.06 | 49.5 | 190.7 | Charlotte Amalie, St. Thomas, USVI
| GFAL | 18.09 | 65.52 | 43.5 | 234.7 | Playa Grande, Vieques, PR
| %IMP | -36% | -23%
|
|
19/0000 UTC 18.1N 63.1W Anguilla 72 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
|
| AVNN | 19.10 | 64.68 | 76.0 | 200.1 | Near Anegada, British Virgin Islands
| AVAL | 18.32 | 63.13 | 59.0 | 24.6 | The Valley, Anguilla
| %IMP | -225% | 88%
|
| GFNO | 18.81 | 64.50 | 53.0 | 167.3 | Near Anegada, British Virgin Islands
| GFAL | 18.37 | 65.04 | 46.5 | 206.9 | Charlotte Amalie, St. Thomas, USVI
| %IMP | -34% | -24%
|
|
19/0600 UTC 18.0N 62.9W St. Barthelemy 78 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 19.10 | 64.68 | 76.0 | 223.8 | Near Anegada, British Virgin Islands
| AVAL | 18.32 | 63.13 | 59.0 | 43.1 | The Valley, Anguilla
| %IMP | -850% | 81%
|
| GFNO | 18.81 | 64.50 | 53.0 | 191.2 | Near Anegada, British Virgin Islands
| GFAL | 18.75 | 64.32 | 51.0 | 171.3 | Anegada, British Virgin Islands
| %IMP | -8% | 10%
|
|
20/0000 UTC 17.3N 61.8W Antigua 96 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 19.10 | 64.68 | 76.0 | 363.8 | Near Anegada, British Virgin Islands
| AVAL | 18.32 | 63.13 | 59.0 | 180.6 | The Valley, Anguilla
| %IMP | -85% | 50%
|
| GFNO | 18.81 | 64.50 | 53.0 | 330.9 | Near Anegada, British Virgin Islands
| GFAL | 18.75 | 64.32 | 51.0 | 311.2 | Anegada, British Virgin Islands
| %IMP | -5% | 6%
| | ||||||||||||||||||||||||||||||||||||||||
Figure 1. NCEP 850 - 200 hPa mean wind analysis for 16 November 1999 0000 UTC (Hurricane Lenny).
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 16 November 1999 0000 UTC. The best track is shown in black.
Figure 3. Ensemble perturbation variance at the nominal sampling time 16 November 1999 0000 UTC from the previous day NCEP ensemble forecast. The green 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 16 November 1999 0000 UTC. The green circles represent the dropwindsonde locations.
