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Tropical Depression TWO Forecast Discussion Number 2
2016-05-28 04:36:55| National Hurricane Center (Atlantic)
Issued at 1100 PM EDT FRI MAY 27 2016 000 WTNT42 KNHC 280236 TCDAT2 TROPICAL DEPRESSION TWO DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL022016 1100 PM EDT FRI MAY 27 2016 The cloud pattern of the depression has not changed much during the past few hours, and the associated deep convection is confined to a somewhat linear band north and northwest of the center. The initial intensity remains 30 kt, consistent with a blend of the latest TAFB and SAB Dvorak estimates. The biggest positive factor for the cyclone intensifying in the next 12 to 36 hours is its movement over the Gulf Stream, where SSTs are above 27C. However, moderate to strong vertical shear and dry air argue against significant strengthening. Given these competing factors, the official forecast continues to show modest intensification during the first 24-36 hours. This forecast is closest to the SHIPS model. After 36 hours, a track over cooler shelf waters and an increase in shear should result in slow weakening, with the system expected to become a remnant low in about 3 days. The initial motion estimate is 300/10, with the depression currently situated between a mid/upper-level low over the northwest Bahamas and a narrow mid-level ridge extending east of the North Carolina coast. These features should result in a continued west- northwestward track for the next 24 hours. After that time, both of these synoptic steering features weaken while a broad mid/upper- level trough moves into the eastern United States. This pattern suggests that the cyclone will slow down and gradually turn northward and then northeastward in 2-3 days. Through day 3 the NHC track is close to a blend of the GFS and ECMWF models, and lies a bit to the right of the previous official forecast, especially at 48 and 72 hours. After that time the global model spread is larger. The ECMWF shows the remnant low moving more quickly northeastward, while the GFS and GEFS ensemble mean show a motion back toward the west at days 4-5. The NHC forecast late in the period still favors the ECMWF track, but is slower given the latest GFS/GEFS trend. FORECAST POSITIONS AND MAX WINDS INIT 28/0300Z 29.0N 75.9W 30 KT 35 MPH 12H 28/1200Z 30.0N 77.3W 35 KT 40 MPH 24H 29/0000Z 31.3N 78.9W 40 KT 45 MPH 36H 29/1200Z 32.2N 79.7W 40 KT 45 MPH 48H 30/0000Z 32.7N 79.7W 35 KT 40 MPH 72H 31/0000Z 33.5N 78.2W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 01/0000Z 34.0N 77.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 02/0000Z 34.5N 76.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Brennan
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