Show Selection: |
#909482 (Received by flhurricane at: 3:35 PM 07.Nov.2017) TCDAT4 Tropical Storm Rina Discussion Number 7 NWS National Hurricane Center Miami FL AL192017 500 PM AST Tue Nov 07 2017 Satellite images show that Rina has a sheared appearance with an asymmetric area of convection near and northeast of the center along with a large cloud shield in the northern semicircle. An earlier ASCAT pass had 35 kt winds well east of the center and, given that the pass likely missed the strongest winds, the wind speed is set to 40 kt on this advisory. Rina is moving in a moderate shear, marginally unstable environment characterized by cool upper-level temperatures counteracting cool SSTs. These conditions along the path of the cyclone don't change much during the next 24-36 hours, so a continuation of the slow increase in wind speed is forecast. After that time, Rina is forecast to move over much colder water into higher shear, which should cause weakening, and will eventually turn Rina into an extratropical cyclone in about 2 days. Most of the models show only slight strengthening over the next day or so, and the official forecast follows suit, close to the SHIPS model for a peak intensity. Rina is moving northward, now at 16 kt. The storm should turn to the north-northeast around a high over the eastern Atlantic late tomorrow. Rina should move quite rapidly to the northeast on Thursday as it becomes embedded within strong mid-latitude flow. The global models, other than some forward speed differences, remain in good agreement, and the latest forecast is basically an update of the previous one, near the corrected-consensus models. Most of the guidance stretch the system out over the North Atlantic, causing the low to dissipate by 72 hours west of Ireland. FORECAST POSITIONS AND MAX WINDS INIT 07/2100Z 33.8N 48.9W 40 KT 45 MPH 12H 08/0600Z 36.2N 48.5W 45 KT 50 MPH 24H 08/1800Z 39.4N 48.0W 50 KT 60 MPH 36H 09/0600Z 43.0N 46.2W 50 KT 60 MPH 48H 09/1800Z 48.0N 41.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 72H 10/1800Z...DISSIPATED $$ Forecaster Blake |