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| #1025476 (Received by flhurricane at: 3:45 PM 15.Nov.2020) TCDAT1 Hurricane Iota Discussion Number 10 NWS National Hurricane Center Miami FL AL312020 400 PM EST Sun Nov 15 2020 The satellite presentation of Iota has continued to improve this afternoon. A ragged eye has become apparent in visible satellite imagery, with excellent banding features surrounding it. An Air Force Reserve Hurricane Hunter aircraft measured a minimum central pressure of 977 mb during its first pass through the center earlier this afternoon, and recorded around 974 mb on its second pass. Somewhat surprisingly, the plane only measured peak 700-mb flight-level winds of 74 kt and SFMR winds of 68 kt. Those winds support an intensity slightly lower than what was previously estimated, but given the low central pressure and downward trend, plus the fact that the plane only made a single pass in each quadrant, it is possible that the maximum winds were not sampled. In addition, the satellite presentation and pressure fall may be preceding the winds slightly. Therefore, the initial is again set at 80 kt. Another Air Force Reserve reconnaissance aircraft is en route and should provide additional information on Iota`s intensity this evening. Very favorable atmospheric and oceanic conditions consisting of low vertical wind shear and warm waters are expected to lead to rapid strengthening until the center crosses the coast of Central America. The NHC intensity forecast again calls for Iota to reach major hurricane strength tonight, and become an extremely dangerous category 4 hurricane before it reaches the coast of Central America Monday night. The NHC intensity forecast is similar to the previous advisory and shows a peak slightly above the latest HFIP corrected consensus model. After landfall, rapid weakening should occur as Iota moves over the mountainous terrain of Central America. Iota is moving westward to west-northwestward at about 8 kt. The track forecast philosophy is unchanged from before. A strong mid-level ridge that extends across the western Atlantic and Florida will steer Iota westward to west-northwestward through landfall Monday night. Once Iota moves over Central America, a westward to west-southwestward motion is expected. The updated NHC track forecast has been adjusted southward through 24 hours, but little overall change was required thereafter. The official forecast lies near the middle of the tightly clustered dynamical model envelope. In addition to potentially catastrophic winds, Iota is expected to bring a life-threatening storm surge and extreme rainfall impacts to portions of Central America. This comes less than two weeks after Hurricane Eta significantly impacted the area. Key Messages: 1. Iota is expected to continue to rapidly intensify and be an extremely dangerous category 4 hurricane when it approaches the coast of Central America on Monday. Potentially catastrophic winds and a life-threatening storm surge are expected along portions of the coast of northeastern Nicaragua and eastern Honduras where a hurricane warning is in effect. 2. Hurricane conditions are expected and storm surge impacts are possible on Providencia tonight and Monday. Tropical storm conditions are expected and hurricane conditions are possible on San Andres. 3. Through Friday morning, heavy rainfall from Iota will likely lead to life-threatening flash flooding and river flooding across portions of Central America. Flooding and mudslides in Honduras and Nicaragua could be exacerbated by Hurricane Etas recent effects there, resulting in significant to potentially catastrophic impacts. FORECAST POSITIONS AND MAX WINDS INIT 15/2100Z 13.3N 79.3W 80 KT 90 MPH 12H 16/0600Z 13.6N 80.5W 100 KT 115 MPH 24H 16/1800Z 14.0N 82.1W 120 KT 140 MPH 36H 17/0600Z 14.3N 83.6W 105 KT 120 MPH...INLAND 48H 17/1800Z 14.4N 84.9W 60 KT 70 MPH...INLAND 60H 18/0600Z 14.3N 86.3W 35 KT 40 MPH...INLAND 72H 18/1800Z 14.1N 87.9W 25 KT 30 MPH...INLAND 96H 19/1800Z...DISSIPATED $$ Forecaster Brown |