Hurricane Vance Forecast Discussion
|
Español: Aviso Publico Discusión |
000 WTPZ42 KNHC 231443 TCDEP2 Hurricane Vance Discussion Number 9 NWS National Hurricane Center Miami FL EP222026 900 AM CST Fri Oct 23 2026 Satellite imagery indicates that Vance continues to get better organized this morning. The hurricane has a well-defined central dense overcast with occasional hints of an eye trying to form and eyewall cloud tops poking up through the overcast. The hurricane also has a large complex of outer bands in the northeastern semicircle. Satellite intensity estimates are in the 70-79 kt range, and they have trended upward slightly since the last advisory. The initial intensity is set at 80 kt. Vance is currently undergoing steady to rapid strengthening and a very favorable atmospheric environment. However, there are two issues that seriously complicate the intensity forecast. First, the previous tropical cyclones that have moved through the area near Vance's forecast track have caused a significant decrease in both oceanic heat content and sea surface temperatures north of where the center is now. Indeed, sea surface temperatures at a drifting buoy about 25 n mi from the center of Vance have fallen below 28C just during the past few hours. This cold pool is likely to halt intensification, and it may take Vance a couple of days to get past it. Second, southwesterly and westerly vertical wind shear is forecast to increase by 24 h, and in combination with the colder water could cause the cyclone to weaken. The new intensity forecast follows the scenario shown by the HAFS models, which shows weakening while the cyclone is over the colder water followed by modest re-intensification. It should be noted that a track to the right of the forecast track will keep the center over the colder water for a longer time, while a track to the left would reduce how much time the center spends over the cold pool. If it is not already apparent, this intensity forecast is low confidence. The center has reformed or jogged to the west during the past few hours, and the initial motion is a somewhat uncertain 325/4 kt. Vance is currently being steered by a weak mid-level ridge over eastern Mexico and the eastern Pacific, and later in the forecast period it will come under the influence of a large mid- to upper-level trough over the western United States as well as the adjacent portions of northern Mexico and the northeastern Pacific. While the dynamical models agree on the general synoptic pattern, the track forecast is complicated by the possibilities of how strong and vertically stacked Vance will be. A stronger and more vertically stacked Vance, especially as depicted in the GFS, will likely move slowly toward the north-northwest and north during the forecast period. On the other hand, the UKMET and Canadian forecast Vance to be weaker and shear apart, with the low-level center being steered more to the northwest before eventually turning northward. The track forecast follows the scenario that Vance will stay vertically coupled, and the new forecast track is similar to the previous track. However, it lies to the left of the Google DeepMind Ensemble Mean, the HFIP Corrected Consensus, and the Florida State Superensemble. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 10.7N 102.1W 80 KT 90 MPH 12H 24/0000Z 11.3N 102.5W 95 KT 110 MPH 24H 24/1200Z 12.3N 102.9W 100 KT 115 MPH 36H 25/0000Z 13.3N 103.3W 95 KT 110 MPH 48H 25/1200Z 14.4N 103.6W 90 KT 105 MPH 60H 26/0000Z 15.3N 103.9W 85 KT 100 MPH 72H 26/1200Z 15.9N 104.2W 90 KT 105 MPH 96H 27/1200Z 16.6N 104.4W 90 KT 105 MPH 120H 28/1200Z 17.5N 104.5W 75 KT 85 MPH $$ Forecaster Beven