je.st
news
Hurricane GONZALO Forecast Discussion Number 27
2014-10-19 04:50:32| National Hurricane Center (Atlantic)
Issued at 1100 PM AST SAT OCT 18 2014 000 WTNT43 KNHC 190250 TCDAT3 HURRICANE GONZALO DISCUSSION NUMBER 27 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082014 1100 PM AST SAT OCT 18 2014 Gonzalo has been maintaining a central dense overcast feature over the large eye feature noted in microwave satellite imagery since the previous advisory. A 19/0116 UTC ASCAT-B high-resolution overpass indicated 78-80 kt surface winds in the eastern quadrant about 45 nmi southeast of the center, so the intensity remains 80 kt for this advisory, which could be a conservative estimate. The same ASCAT pass also indicted that the wind field in the southeastern semicircle had expanded significantly, and the respective wind radii have been increased accordingly. Gonzalo continues to accelerate toward the northeast and the initial motion estimate is 040/34 kt. The latest 0000 UTC model guidance remains tightly packed, so no significant changes were made to the previous forecast track. Gonzalo should continue to move northeastward and then east-northeastward in the flow between a deep-layer trough to the west of the hurricane and a subtropical ridge to its south. The NHC forecast track is just an update of the previous advisory track, and lies close to the consensus model TVCA. The post-tropical portion of the forecast track was coordinated with the NOAA Ocean Prediction Center. Recent SST analyses and the forecast motion indicate that Gonzalo should continue to move over a thermal ridge for a few more hours, which should help the cyclone maintain status as a tropical cyclone. By 12 hours, however, SSTs less than 12C and increasing southwesterly vertical wind shear of more than 30 kt should result in Gonzalo making the transition to a strong post-tropical extratropical cyclone. Gradual weakening is forecast after the transition occurs and to continue until dissipation occurs in by 72 hours. The NHC intensity forecast follows the Decay-SHIPS model through 12 hours, and then is based on input from the Ocean Prediction Center. FORECAST POSITIONS AND MAX WINDS INIT 19/0300Z 42.3N 57.0W 80 KT 90 MPH 12H 19/1200Z 47.0N 50.5W 70 KT 80 MPH...POST-TROP/EXTRATROP 24H 20/0000Z 52.0N 38.5W 60 KT 70 MPH...POST-TROP/EXTRATROP 36H 20/1200Z 54.0N 24.0W 50 KT 60 MPH...POST-TROP/EXTRATROP 48H 21/0000Z 57.0N 8.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 72H 22/0000Z...DISSIPATED $$ Forecaster Stewart
Tags: number
discussion
forecast
hurricane
Category:Transportation and Logistics