TROPICAL DEPRESSION ONE DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL012012
1000 PM EDT SUN APR 15 2012

SATELLITE IMAGERY AND DATA DERIVED FROM AN EARLIER ASCAT PASS REVEALS THAT THE WELL-DEFINED AREA OF LOW PRESSURE IN THE NORTHWESTERN CARIBBEAN HAS GAINED ENOUGH ORGANIZATION TO BE DECLARED A TROPICAL DEPRESSION, THE FIRST OF THE SEASON. THE INITIAL WINDSPEED IS SET AT 30 KT BASED ON A FEW 30 KT WIND BARBS ON THE EARLIER ASCAT PASS. THE DEPRESSION IS OVER WARM WATER BUT IN AN AREA OF MODERATE SOUTHWESTERLY VERTICAL WIND SHEAR WITH DRY AIR TO ITS NORTH AND WEST. THE ENVIRONMENT OVER THE NEXT COUPLE OF DAYS IS NOT HIGHLY CONDUCIVE FOR STRENGTHENING...BUT SHOULD NOT BE HOSTILE ENOUGH TO PREVENT THE SYSTEM FROM BECOMING A TROPICAL STORM. THE OFFICIAL FORECAST LIES SLIGHTLY ABOVE THE DYNAMICAL SHIPS/LGEM GUIDANCE.

THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 325/5. THE CYCLONE IS FORECAST TO MOVE IN THIS GENERAL DIRECTION OVER THE FEW DAYS BEFORE TURNING TOWARDS THE NORTH AND EAST IN RESPONSE TO A COLD FRONT APPROACHING FROM THE NORTHWEST. THE UNCERTAINTY IN THE FORECAST TRACK INCREASES GREATLY AFTER THE 3 TO 5 DAY TIMEFRAME. THE GFS AND NOGAPS MODEL MOVE THE DEPRESSION INLAND OVER THE YUCATAN PENINSULA BEFORE ENTERING THE GULF OF MEXICO. MEANWHILE, THE ECMWF AND CMC KEEP THE SYSTEM OFFSHORE AND TURN IT GRADUALLY NORTHEASTWARD TOWARDS THE EASTERN TIP OF CUBA. GIVEN THE STRENGTH OF THE APPROACHING COLD FRONT, THE LATTER SOLUTION SEEMS MORE LIKELY, AND THE DEPRESSION COULD BE APPROACHING SOUTHERN FLORIDA BY THE END OF THE FORECAST PERIOD.


FORECAST POSITIONS AND MAX WINDS

INIT  23/2100Z 15.9N  81.9W   30 KT  35 MPH
 12H  24/0600Z 16.4N  82.2W   30 KT  35 MPH
 24H  24/1800Z 16.8N  82.9W   35 KT  40 MPH
 36H  25/0600Z 17.0N  83.5W   40 KT  45 MPH
 48H  25/1800Z 17.1N  84.3W   40 KT  45 MPH
 72H  26/1800Z 17.3N  86.0W   40 KT  45 MPH
 96H  27/1800Z 17.7N  87.0W   35 KT  40 MPH
120H  28/1800Z 19.0N  88.0W  30 KT 35 MPH

$$
FORECASTER FIELDS

NNNN