je.st
news
Tropical Storm Eta Forecast Discussion Number 48
2020-11-12 09:54:47| National Hurricane Center (Atlantic)
Issued at 400 AM EST Thu Nov 12 2020 000 WTNT44 KNHC 120854 TCDAT4 Tropical Storm Eta Discussion Number 48 NWS National Hurricane Center Miami FL AL292020 400 AM EST Thu Nov 12 2020 Satellite images indicate that Eta has lost most of its central deep convection over the past several hours, with the radar center becoming poorly defined and decreasing winds aloft noted. The last Air Force Hurricane Hunter mission found winds to support about 50 kt, and with the continued loss of organization, the current wind speed is lowered to 45 kt. The tropical cyclone should be making landfall in the Cedar Key area soon. Eta is forecast to weaken over its short passage over the Florida peninsula later today, and over the western Atlantic tonight due to strong shear. There has been a change in some of the guidance showing the tropical cyclone re-gaining strength as a non-tropical low after 24 hours due to a more favorable positioning with the next mid-latitude trough near the Great Lakes on Friday. The strongest solutions are seen in the UKMET and ECMWF models, which indicate even storm-force winds are possible in a few days. I'd rather wait one more cycle to see if this trend continues but, as a compromise, the new forecast shows some re-strengthening as an extratropical cyclone and reverses any former weakening trend. The storm is moving a little faster to the northeast this morning. Eta should accelerate even more in that direction later today as it becomes steered by the faster middle-latitude flow. The new forecast shows a more rapid forward speed than the previous advisory, which is related to the ECMWF/UKMET model solutions of Eta showing some extratropical intensification and staying coherent, rather than shearing out as a weak low like the GFS. Eta should merge with a large non-tropical low in 2 to 3 days. Key Messages: 1. There remains a danger of life-threatening storm surge along portions of the Florida Gulf Coast from the Middle of Longboat Key to the Suwannee River, including Tampa Bay. Residents in this area should follow any advice given by local officials. 2. Tropical-storm-force winds are expected in the warning area along portions of the Florida Gulf Coast during the next few hours, and in the warning area on the east coast later today. 3. Localized bands of heavy rainfall will continue to impact portions of the Florida Peninsula today, resulting in isolated flash and urban flooding, especially across previously inundated areas. Minor river flooding is expected across portions of west Florida lasting into the weekend. FORECAST POSITIONS AND MAX WINDS INIT 12/0900Z 29.1N 83.0W 45 KT 50 MPH 12H 12/1800Z 30.6N 81.4W 40 KT 45 MPH 24H 13/0600Z 32.6N 78.1W 35 KT 40 MPH 36H 13/1800Z 35.2N 73.4W 40 KT 45 MPH...POST-TROP/EXTRATROP 48H 14/0600Z 38.0N 67.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 60H 14/1800Z...DISSIPATED $$ Forecaster Blake
Tags: number
discussion
storm
tropical
Category:Transportation and Logistics