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Hurricane Epsilon Forecast Discussion Number 12
2020-10-21 22:55:09| National Hurricane Center (Atlantic)
Issued at 500 PM AST Wed Oct 21 2020 000 WTNT42 KNHC 212055 TCDAT2 Hurricane Epsilon Discussion Number 12 NWS National Hurricane Center Miami FL AL272020 500 PM AST Wed Oct 21 2020 Epsilon has continued to defy expectations and rapidly intensify this afternoon. The satellite presentation of the hurricane is very impressive, with a warm well-defined eye and a closed ring of eyewall convection with cloud tops colder than -60 deg C. An Air Force Hurricane Hunter aircraft that investigated Epsilon earlier today measured SFMR winds of around 100 kt and max flight level winds of 100 kt. Dropsonde data indicated peak surface winds of 106 kt with deeper-layer averages of 95-100 kt, which also lends support to the higher SFMR winds, and surface pressures have fallen since the special advisory. Therefore the initial intensity is raised to 100 kt, making Epsilon the 4th major hurricane of the season. Epsilon's estimated motion is 305/9 kt, and the hurricane is expected to gradually turn more northwestward tonight as it is steered by a mid-level ridge building to its north and east. Epsilon is forecast to pass east of Bermuda and make its closest approach to the island Thursday afternoon or evening. As the ridge becomes oriented east of the hurricane, Epsilon will turn northward and move into the mid-latitudes, where it is expected to accelerate northeastward across the central Atlantic this weekend. There was a westward shift noted in a couple of the track models, and the NHC track forecast has been adjusted slightly westward in the near-term period to better reflect the guidance consensus. As Epsilon continues to gain latitude, environmental conditions will become increasingly unfavorable for additional strengthening. The hurricane is forecast to move over cooler waters beginning tonight, and southerly deep-layer shear is expected within the next 24-48 h. With that being said, small intensity fluctuations cannot be completely ruled out tonight given Epsilon's development trends and well-organized structure. The NHC intensity forecast lies closest to the SHIPS guidance for the first 24-36 h of the forecast period. Afterwards, the official forecast shows more steady weakening with the possibility of an eyewall replacement cycle, and the new NHC intensity prediction follows the intensity consensus. Epsilon could begin its extratropical transition by Sunday night, and it is forecast to be a powerful extratropical cyclone over the northeastern Atlantic by day 5. Key Messages: 1. Tropical storm conditions are expected on Bermuda beginning this evening and continuing intermittently through late Thursday, when Epsilon is forecast to make its closest approach east of the island. A Tropical Storm Warning is in effect for Bermuda. 2. Dangerous surf and rip currents are likely occurring along the coasts of Bermuda, the Bahamas, the Greater Antilles, and the Leeward Islands. These conditions are expected to spread to portions of the east coast of the United States and Atlantic Canada during the next couple of days. FORECAST POSITIONS AND MAX WINDS INIT 21/2100Z 29.6N 60.0W 100 KT 115 MPH 12H 22/0600Z 30.5N 60.9W 100 KT 115 MPH 24H 22/1800Z 31.8N 61.6W 95 KT 110 MPH 36H 23/0600Z 33.0N 62.0W 90 KT 105 MPH 48H 23/1800Z 34.4N 62.1W 85 KT 100 MPH 60H 24/0600Z 36.2N 61.8W 85 KT 100 MPH 72H 24/1800Z 38.3N 59.8W 80 KT 90 MPH 96H 25/1800Z 44.5N 47.5W 70 KT 80 MPH 120H 26/1800Z 54.0N 28.5W 65 KT 75 MPH...POST-TROP/EXTRATROP $$ Forecaster Reinhart/Blake
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