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| #1025284 (Received by flhurricane at: 10:03 AM 14.Nov.2020) TCDAT1 Tropical Storm Iota Discussion Number 5 NWS National Hurricane Center Miami FL AL312020 1000 AM EST Sat Nov 14 2020 Recent microwave satellite imagery and early morning visible pictures show that Iota remains a sheared tropical cyclone, with the center located near the southwestern edge of the main convective mass. The initial intensity is held at 35 kt and is based on the earlier ASCAT data and recent satellite estimates. An Air Force Reserve reconnaissance aircraft is scheduled to investigate Iota early this afternoon. Somewhat surprisingly Iota has not strengthened much since yesterday, which appears to be the result of some unexpected shear and its close proximity to the northwest coast of Colombia. The global models predict that the shear will relax soon, and that the system will be in quite favorable conditions for strengthening. The NHC forecast again calls for steady to rapid strengthening in the next 12-60 h once the storm organizes enough to take advantage of the expected favorable conditions. The updated NHC intensity is similar to the previous forecast and shows Iota at or near major hurricane strength when it approaches the coast of Central America. Although the center of Iota was relocated to the south and west of the earlier estimates, the long-term initial motion estimate is 255/4 kt. The track forecast reasoning remains unchanged from the previous advisory. A mid-level ridge over the Gulf of Mexico is expected to build eastward to the north of Iota during the next day or two, and this feature should cause the cyclone to move westward to west-northwestward at a faster forward speed during the next few days. This should bring the center near the coast of northeastern Nicaragua or Honduras in 2 to 3 days. After landfall, a west-southwestward motion is expected with Iota moving inland over Central America. The new NHC track forecast has been adjusted southward, especially in the first 24 to 36 hours due to the more southward initial position. The NHC track lies close to the TVCA multi-model consensus, which is between the lastest global model interpolated trackers and the model fields. Key Messages: 1. Iota is expected to strengthen and be at or near major hurricane strength when it approaches the coast of Central America. There is a risk of dangerous wind, storm surge, and rainfall impacts across portions of Nicaragua and Honduras beginning Monday. Hurricane Watches will likely be issued for a portion of this area later today. Tropical Storm Warnings are in effect for the islands of San Andres and Providencia. 2. Through Thursday, heavy rainfall from Iota will likely lead to life-threatening flash flooding and river flooding across portions of northern Colombia and Central America. Flooding and mudslides in Honduras and Nicaragua could be exacerbated by Hurricane Etas recent effects there, resulting in significant impacts. FORECAST POSITIONS AND MAX WINDS INIT 14/1500Z 12.7N 76.2W 35 KT 40 MPH 12H 15/0000Z 12.9N 76.8W 45 KT 50 MPH 24H 15/1200Z 13.4N 78.2W 55 KT 65 MPH 36H 16/0000Z 13.9N 80.0W 70 KT 80 MPH 48H 16/1200Z 14.2N 81.6W 85 KT 100 MPH 60H 17/0000Z 14.4N 83.0W 95 KT 110 MPH 72H 17/1200Z 14.5N 84.3W 75 KT 85 MPH...INLAND 96H 18/1200Z 14.3N 86.7W 35 KT 40 MPH...INLAND 120H 19/1200Z 13.5N 90.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Brown |