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#1024755 (Received by flhurricane at: 4:02 AM 11.Nov.2020) TCDAT4 Tropical Storm Eta Discussion Number 44 NWS National Hurricane Center Miami FL AL292020 400 AM EST Wed Nov 11 2020 Eta has become better organized over the past few hours, with a better-defined eye feature on the Key West radar. Satellite pictures also show a more symmetric presentation and a large cluster of deep convection near the center. Radar data has shown increasing wind speeds in the mid-levels, which supports conservatively raising the initial wind speed to 60 kt. The current position is southwest of the eye feature on radar, assuming some shear remains, but a NOAA Hurricane Hunter aircraft is scheduled to be in the storm in a few hours to acquire better data on both the initial position and intensity. It appears that the center of Eta has re-formed to the north- northeast tonight, so an initial motion is hard to determine, but is estimated to be northward at about 10 kt. Remarkably, model guidance has become well clustered just east of the previous forecast track as it seems apparent that Eta will now recurve around the ridge toward the Florida Big Bend region and out into the western Atlantic Ocean. The biggest change is that the models are faster than before, and the official forecast follows that lead, along with a small eastward forecast adjustment, near or just east of the model consensus. Further strengthening is possible today while the shear remains low-to-moderate. However, all of the models do show increasing shear by tonight, and the NHC forecast continues to call for weakening of Eta as it approaches the west coast of Florida. However, it would take only a small forecast error to allow Eta to come ashore as a hurricane, and hence a Hurricane Watch has been issued this morning. Rapid weakening is anticipated once Eta makes landfall, and strong shear should prevent any regeneration over the western Atlantic Ocean. The new forecast is a little higher than the previous advisory, mostly due to current trends, and is closer to the more bullish HMON and HWRF models. Key Messages: 1. Life-threatening storm surge is possible early Thursday along portions of the Florida Gulf Coast from Bonita Beach to Steinhatchee River, including Tampa Bay and Charlotte Harbor. Residents in this area should follow any advice given by local officials. 2. Hurricane-force winds are possible along portions of the west coast of Florida from Anna Maria Island to Yankeetown by early Thursday. Tropical-storm-force winds are expected by late Wednesday along portions of the Florida Gulf Coast from Bonita Beach to Suwanee River, and are possible Thursday from Suwannee River to Aucilla River. Interests elsewhere along the Florida Gulf Coast should monitor the progress of Eta, as additional watches and warnings may be needed today. 3. Heavy rainfall from Eta will continue across western Cuba and South Florida and spread northward across portions of West and North Florida Wednesday through Friday. Additional flash and urban flooding will be possible in South Florida on Wednesday, especially across previously inundated areas, and across portions of West Florida through Friday. FORECAST POSITIONS AND MAX WINDS INIT 11/0900Z 25.0N 84.1W 60 KT 70 MPH 12H 11/1800Z 26.4N 83.9W 65 KT 75 MPH 24H 12/0600Z 27.9N 83.4W 60 KT 70 MPH 36H 12/1800Z 29.2N 82.6W 45 KT 50 MPH...INLAND 48H 13/0600Z 30.2N 81.2W 30 KT 35 MPH 60H 13/1800Z 30.9N 79.5W 30 KT 35 MPH 72H 14/0600Z 31.0N 78.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 15/0600Z...DISSIPATED $$ Forecaster Blake |