|
Show Selection: |
| #1022723 (Received by flhurricane at: 5:00 PM 26.Oct.2020) TCDAT3 Hurricane Zeta Discussion Number 9 NWS National Hurricane Center Miami FL AL282020 400 PM CDT Mon Oct 26 2020 The cloud pattern of Zeta became better organized today, with deep convection forming over and around the center and some banding features developing. The Air Force Reserve Hurricane Hunters recently found surface winds to near 70 kt over the inner northeastern quadrant of the circulation and a central pressure of around 981 mb, signifying that the system had become a hurricane. Given the increased organization over very warm waters, some additional strengthening is possible before the center crosses the east coast of the Yucatan Peninsula this evening. Some weakening should occur while Zeta interacts with land tonight and early Tuesday. Once the center moves into the southern Gulf of Mexico tomorrow, atmospheric and oceanic conditions are conducive for some re-strengthening. When Zeta moves over the northern Gulf of Mexico later on Wednesday, cooler shelf waters and some increase in southwesterly shear should halt the intensification process, with some weakening possible by the time the center reaches the northern Gulf Coast, but Zeta is still expected to be at or near hurricane intensity at landfall. The NHC intensity forecast is similar to the previous one and is near or above the model consensus. The hurricane continues to move on a generally northwestward track, or at about 305/10 kt. There are basically no changes to the track forecast reasoning, or to the forecast itself. For the next couple of days, Zeta should move around the southwestern and western periphery of a mid-level high pressure area centered just east of Florida. Thereafter, a shortwave trough approaching from the west is likely to cause the cyclone to accelerate north-northeastward to northeastward and move over the southeastern and eastern United States. The system should move off the northeast U.S. coast and become an extratropical cyclone within the next 4 days. The guidance has come into better agreement since yesterday, and the official track forecast is very close to the corrected model consensus, HCCA. Storm Surge, Hurricane, and Tropical Storm Watches have been issued for a portion of the northern U.S. Gulf Coast. KEY MESSAGES: 1. Hurricane conditions and dangerous storm surge are expected in portions of the northern Yucatan Peninsula of Mexico this evening through early Tuesday. Through Tuesday, heavy rainfall is expected across the Yucatan Peninsula, the Cayman Islands, and central to western Cuba, which could lead to flash flooding in urban areas. 2. Hurricane conditions and life-threatening storm surge are possible along portions of the northern Gulf Coast on Wednesday, and Storm Surge and Hurricane Watches are in effect. Residents in the watch areas should follow any advice given by local officials. 3. Between Tuesday night and Thursday, heavy rainfall is expected from portions of the central Gulf Coast into the southern Appalachians and Mid-Atlantic States near and in advance of Zeta. This rainfall will lead to flash, urban, small stream, and minor river flooding. FORECAST POSITIONS AND MAX WINDS INIT 26/2100Z 19.5N 86.0W 70 KT 80 MPH 12H 27/0600Z 20.5N 87.7W 75 KT 85 MPH 24H 27/1800Z 22.1N 89.9W 65 KT 75 MPH 36H 28/0600Z 24.2N 91.4W 70 KT 80 MPH 48H 28/1800Z 26.8N 91.4W 70 KT 80 MPH 60H 29/0600Z 30.8N 88.9W 60 KT 70 MPH...INLAND 72H 29/1800Z 35.0N 83.5W 30 KT 35 MPH...INLAND 96H 30/1800Z 42.0N 68.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 120H 31/1800Z...DISSIPATED $$ Forecaster Pasch |