562 
 WTNT44 KNHC 300852
 TCDAT4
  
 TROPICAL STORM ISAAC DISCUSSION NUMBER  37
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
 400 AM CDT THU AUG 30 2012
  
 ISAAC IS SLOWLY WEAKENING AS MORE OF ITS LARGE CIRCULATION MOVES
 OVER LAND.  BASED ON THE LATEST SURFACE WIND OBSERVATIONS NEAR THE
 NORTHERN GULF COAST...THE MAXIMUM WINDS HAVE DIMINISHED TO NEAR 40
 KT.  THESE WINDS ARE OCCURRING PRIMARILY OVER WATER OR ALONG THE
 COASTLINE.   CONTINUED GRADUAL WEAKENING IS EXPECTED...AND ISAAC IS
 LIKELY TO BECOME A TROPICAL DEPRESSION BY THIS EVENING.  THE
 OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS ONE...AND IS
 MORE OR LESS IN AGREEMENT WITH THE STATISTICAL-DYNAMICAL GUIDANCE.
  
 CENTER FIXES USING SURFACE SYNOPTIC DATA AND NATIONAL WEATHER
 SERVICE DOPPLER RADAR IMAGERY INDICATE THAT ISAAC IS MOVING
 NORTHWESTWARD AT A SLIGHTLY FASTER PACE...325/7.  THE TRACK
 FORECAST AND PROGNOSTIC REASONING REMAIN ESSENTIALLY UNCHANGED.
 OVER THE NEXT SEVERAL DAYS...THE PRIMARY STEERING MECHANISM SHOULD
 BE THE FLOW BETWEEN THE MID-LATITUDE WESTERLIES AND A RIDGE OVER
 THE SOUTHEASTERN UNITED STATES.  AS A RESULT THE CYCLONE IS
 EXPECTED TO TURN NORTHWARD...NORTHEASTWARD...AND EASTWARD DURING
 THE FORECAST PERIOD.  THE OFFICIAL TRACK FORECAST IS VERY CLOSE TO
 THE PREVIOUS ONE...AND ALSO CLOSE TO THE LATEST DYNAMICAL MODEL
 CONSENSUS.
  
 HEAVY RAINFALL AND A SIGNIFICANT FLOOD THREAT ARE EXPECTED TO SPREAD
 INLAND ACROSS PORTIONS OF THE CENTRAL UNITED STATES DURING THE NEXT
 SEVERAL DAYS.  WATER LEVELS ALONG THE NORTHERN GULF COAST WILL
 REMAIN ELEVATED THROUGH AT LEAST THIS MORNING.  TORNADOES REMAIN A
 THREAT AS WELL FROM THIS SYSTEM TODAY. 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  30/0900Z 30.9N  91.6W   40 KT  45 MPH
  12H  30/1800Z 31.9N  92.3W   35 KT  40 MPH...INLAND
  24H  31/0600Z 33.8N  93.2W   30 KT  35 MPH...INLAND
  36H  31/1800Z 36.0N  93.5W   25 KT  30 MPH...INLAND
  48H  01/0600Z 38.0N  93.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
  72H  02/0600Z 39.5N  90.0W   15 KT  15 MPH...POST-TROP/REMNT LOW
  96H  03/0600Z 40.0N  86.5W   15 KT  15 MPH...POST-TROP/REMNT LOW
 120H  04/0600Z 40.5N  82.0W   15 KT  15 MPH...POST-TROP/REMNT LOW
  
 $$
 FORECASTER PASCH