Effects of Synoptic Surveillance on model forecasts for
16 November 1999 1200 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 | 171. | 101. | 55. | 62. | 206. | 367. | 527. | 572. | 688. | 747.
| AVAL | 11. | 39. | 129. | 240. | 402. | 624. | 821. | 962. | 1163. | 1211.
| %IMP | 94% | 61% | -134% | -287% | -95% | -70% | -56% | -68% | -69% | -62%
|
| GFNO | 106. | 132. | 108. | 156. | 344. | 573. | 769. | 975. | 1258. | 1465.
| GFAL | 87. | 139. | 67. | 158. | 357. | 551. | 730. | 924. | 1199. | 1401.
| %IMP | 18% | -5% | 38% | -1% | 4% | 4% | 5% | 5% | 5% | 4%
| INTENSITY (kt)
| MODEL | 12 h | 24 h | 36 h | 48 h | 60 h | 72 h | 84 h | 96 h | 108 h | 120 h
|
| AVNN | -62. | -79. | -95. | -91. | -58. | -42. | -22. | -19. | -13. | -3.
| AVAL | -60. | -78. | -96. | -89. | -56. | -42. | -25. | -14. | -5. | 2.
| %IMP | 3% | 1% | -1% | 2% | 3% | 0% | -17% | 26% | 62% | 33%
|
| GFNO | 11. | -3. | -20. | -15. | 23. | 33. | 46. | 46. | 58. | 61.
| GFAL | 18. | 2. | -25. | -19. | 20. | 37. | 39. | 42. | 64. | 66.
| %IMP | -64% | 33% | -25% | -27% | 13% | -12% | 15% | 9% | -10% | -8%
|
| SHNO | -11. | -25. | -44. | -42. | -12. | -15. | -4. | -4. | 1. | 7.
| SHAL | -11. | -27. | -46. | -44. | -14. | -15. | -4. | -4. | 2. | 8.
| %IMP | 0% | -8% | -5% | -5% | -17% | 0% | 0% | 0% | -100% | -14%
|
| DSNO | -11. | -25. | -44. | -42. | -12. | -15. | -4. | -4. | 1. | 7.
| DSAL | -11. | -27. | -46. | -44. | -14. | -15. | -4. | -4. | 2. | 8.
| %IMP | 0% | -8% | -5% | -5% | -17% | 0% | 0% | 0% | -100% | -14%
| | ||||||||||
| 17/1800 UTC 17.4N 64.8W St. Croix, USVI 30 h into the forecast | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 17.36 | 64.27 | 38.0 | 56.4 | Near Christiansted, St. Croix, USVI
| AVAL | 17.75 | 64.58 | 28.5 | 45.3 | Christiansted, St. Croix, USVI
| %IMP | 81% | 20%
|
| GFNO | 17.92 | 65.07 | 41.0 | 64.5 | Near Frederiksted, St. Croix, USVI
| GFAL | 17.74 | 64.88 | 35.5 | 38.7 | Frederiksted, St. Croix, USVI
| %IMP | 50% | 40%
|
|
18/1800 UTC 18.0N 63.3W St. Martin 54 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.20 | 63.10 | 48.0 | 30.7 | The Valley, Anguilla
| AVAL | 18.10 | 63.10 | 36.0 | 23.9 | Quartier du Colombier, St Martin
| %IMP | -200% | 22%
|
| GFNO | 18.40 | 64.51 | 41.0 | 135.2 | Road Town, Tortola, British Virgin Islands
| GFAL | 18.39 | 64.04 | 41.0 | 89.3 | Near Virgin Gorda, British Virgin Islands
| %IMP | 0% | 34%
|
|
|
19/0000 UTC 18.1N 63.1W Anguilla 60 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.20 | 63.10 | 48.0 | 11.1 | The Valley, Anguilla
| AVAL | 18.10 | 63.10 | 36.0 | 0.0 | Quartier du Colombier, St Martin
| %IMP | -100% | 100%
|
| GFNO | 18.65 | 64.23 | 43.0 | 133.9 | Anegada, British Virgin Islands
| GFAL | 18.39 | 64.04 | 41.0 | 104.3 | Near Virgin Gorda, British Virgin Islands
| %IMP | -12% | 22%
|
|
|
19/0600 UTC 18.0N 62.9W St. Barthelemy 66 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
|
| AVNN | 18.20 | 63.10 | 48.0 | 30.7 | The Valley, Anguilla
| AVAL | 18.10 | 63.10 | 36.0 | 23.9 | Quartier du Colombier, St Martin
| %IMP | -67% | 22%
|
| GFNO | 18.65 | 64.23 | 43.0 | 157.8 | Anegada, British Virgin Islands
| GFAL | 18.39 | 64.04 | 41.0 | 127.9 | Near Virgin Gorda, British Virgin Islands
| %IMP | -9% | 19%
|
|
|
20/0000 UTC 17.3N 61.8W Antigua 84 h into the forecast
| MODEL | LAT | LON | TIME | ERROR | LOCATION
|
| AVNN | 18.20 | 63.10 | 48.0 | 171.1 | The Valley, Anguilla
| AVAL | 18.10 | 63.10 | 36.0 | 163.8 | Quartier du Colombier, St Martin
| %IMP | -33% | 4%
|
| GFNO | 18.65 | 64.23 | 43.0 | 297.4 | Anegada, British Virgin Islands
| GFAL | 18.39 | 64.04 | 41.0 | 266.0 | Near Virgin Gorda, British Virgin Islands
| %IMP | -5% | 11%
|
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Figure 1. NCEP 850 - 200 hPa mean wind analysis for 16 November 1999 1200 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 1200 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 16 November 1999 1200 UTC.
