000 WTPZ41 KNHC 030258 TCDEP1 HURRICANE VANCE DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL EP212014 700 PM PST SUN NOV 02 2014 Vance has displayed a pinhole eye surrounded by very cold cloud tops both in microwave imagery and sporadically in visible/infrared imagery. Subjective Dvorak estimates from SAB and TAFB along with a 2124Z AMSU objective analysis from CIMSS indicates an intensity of 90 kt. The combination of very low vertical shear, quite moist and unstable thermodynamics, warm SSTs, and large upper-level divergence have contributed toward Vance's rapid intensification during the last 24 hours, during which time the maximum winds have doubled. Vince has about 12 hours of conducive conditions remaining before a high amplitude upper- to mid-level trough currently west of Baja California begins to adversely affect the tropical cyclone. Vertical shear should quickly ramp up while the moisture, convective instability, and upper-level divergence drop during the next two days. Vance is predicted to peak in intensity shortly followed by rapid weakening, most similar to the LGEM and SHIPS statistical models during the next 24 hours and to the IVCN multi-model consensus thereafter. This forecast is higher than that in the previous advisory due to the stronger initial intensity, but lower at days 2 and 3. Vance is moving 310 degrees at 15 kt, as it is being advected around the periphery of a deep-layer ridge to its northeast. As the aforementioned trough digs southward, Vance should undergo recurvature beginning in about a day, at the very low latitude of about 18 North. The tropical cyclone should then turn toward the north-northeast on Tuesday and start approaching southwestern Mexico. However, the shear should become so severe that the tropical cyclone is likely to decouple in about three days with the remnant low not quite reaching the coast. The NHC official track prediction is based upon the TVCE multi-model consensus, and is faster than the previous advisory but not as far northeast as the GFS-ECMWF combination. An alternative scenario is that Vance reaches the southwestern Mexican coast as a tropical storm in about three days, as seen in the deterministic ECMWF model run. However, given the quite hostile vertical shear conditions expected, and that the ECMWF solution appears to be an outlier compared to its ensemble members, this is not considered to be likely at this time. FORECAST POSITIONS AND MAX WINDS INIT 03/0300Z 13.7N 109.6W 90 KT 105 MPH 12H 03/1200Z 15.2N 110.6W 100 KT 115 MPH 24H 04/0000Z 17.1N 110.8W 90 KT 105 MPH 36H 04/1200Z 18.7N 110.1W 70 KT 80 MPH 48H 05/0000Z 20.4N 108.8W 50 KT 60 MPH 72H 06/0000Z 23.5N 107.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 07/0000Z...DISSIPATED $$ Forecaster Landsea