Issued at 500 PM EDT Fri Sep 13 2019 000WTNT44 KNHC 132043TCDAT4Tropical Depression Nine Discussion Number 5NWS National Hurricane Center Miami FL AL092019500 PM EDT Fri Sep 13 2019An Air Force plane extensively investigated the disturbance near theBahamas during the past several hours, and in the last portion ofthe mission, the crew was able to locate a center of circulation,although weak, near the convection. The center was a little bitto the east of the previous estimates. Satellite images alsoindicate that the cloud pattern has become a little better organizedand Dvorak estimates are T2.0 and 1.5 from TAFB and SAB,respectively. On this basis, the disturbance has been classified asa tropical depression with 25 kt winds.Conditions are not ideal for strengthening since the depressionis still embedded within a moderate shear environment, butthis parameter is not expected to be strong enough to haltadditional development. The NHC forecast still calls for this systemto become a tropical storm on Saturday with gradual intensificationthereafter. Global models insist on further development, and thereliable guidance suggests that the cyclone could even reachhurricane intensity in about 3 days, and so does the NHC forecast.By then, the system is expected to be over the Atlantic waters wellsoutheast of the coast of the Carolinas.Due to the reformation of the apparent center, the initial motion ishighly uncertain. The best estimate is toward the northwest or 305degrees at 7 kt. A weakness in the ridge over the western Atlanticis forecast to develop, and this pattern should steer the systemslowly toward the northwest and then northward. In about 3 days, aneastward moving mid-latitude trough will force the system to recurveaway from the coast toward the Atlantic. The track guidance hasshifted to the east again, and this shift is larger due to theeastward formation of the center. Consequently, the NHC trackforecast was adjusted in that direction, but it remains on thewestern edge of the guidance envelope.Key Messages:1. The depression is forecast to become a tropical storm withinthe next 24 hours and will likely bring tropical-storm-force windsand heavy rainfall to portions of the northwestern Bahamas latertoday and Saturday. Significant storm surge is not expected in thenorthwest Bahamas from this system. Residents there should followany advice given by local officials.2. The system could still bring tropical storm conditions toportions of the Florida east coast. Residents there should monitorthe progress of this system and follow any advice given by localofficials.3. Heavy rainfall and scattered flash flooding is possible thisweekend in coastal sections of eastern Florida, Georgia, and SouthCarolina. The chance of heavy rainfall affecting coastal NorthCarolina early next week continues to diminish.FORECAST POSITIONS AND MAX WINDSINIT 13/2100Z 25.6N 75.0W 25 KT 30 MPH 12H 14/0600Z 26.2N 76.0W 30 KT 35 MPH 24H 14/1800Z 27.4N 77.6W 35 KT 40 MPH 36H 15/0600Z 28.8N 78.5W 45 KT 50 MPH 48H 15/1800Z 30.0N 78.8W 55 KT 65 MPH 72H 16/1800Z 31.5N 76.5W 65 KT 75 MPH 96H 17/1800Z 32.0N 73.0W 70 KT 80 MPH120H 18/1800Z 32.5N 68.0W 75 KT 85 MPH$$Forecaster Avila

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