014 
 WTNT41 KNHC 050237
 TCDAT1
 
 HURRICANE ARTHUR DISCUSSION NUMBER  17
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL012014
 1100 PM EDT FRI JUL 04 2014
 
 Satellite and radar data indicates that Arthur has begun
 extratropical transition.  The eye feature seen previously has
 dissipated, and the remaining convection is now displaced somewhat
 to the northeast of the low-level center.  In addition, microwave
 total precipitable water data from a recent SSM/IS overpass shows
 very dry air entraining into the west and south sides of the
 cyclone.  SFMR data from the previous Air Force Reserve Hurricane
 Hunter flight showed maximum winds of 60-65 kt, and based on this
 the initial intensity is reduced to a possibly generous 65 kt.
 
 The initial motion is now 045/27 kt.  Arthur should continue to move
 northeastward during the next 24-36 hours in deep-layer
 southwesterly flow ahead of a baroclinic trough over the
 northeastern United States.  After that time, the post-tropical
 cyclone is forecast to slow down and eventually turn
 east-northeastward.  Based on the current motion and model trends,
 this part of the forecast has been nudged a little to the east of
 the previous track.  There remains a large amount of spread in the
 track guidance after 48 hours on whether the former Arthur will turn
 more northward or turn east-northeastward out into the Atlantic. The
 new official forecast during that period has been revised based on
 a blend of input from the Ocean Prediction Center along with the
 GFS and ECMWF models.
 
 Arthur is expected to complete extratropical transition in about 12
 hours.  After transition, the former tropical cyclone should
 steadily weaken, with winds dropping below gale force by 96 hours.
 The intensity forecast has been revised downward based on input from
 the OPC, as well as from the GFS and ECMWF models.
 
 Winds in excess of gale/tropical storm force are expected over
 portions of eastern Maine on Saturday.  Because Arthur is expected
 to be extratropical by Saturday morning, and because the strong
 winds in Maine will be post-frontal, this threat is being handled by
 high wind warnings issued by local NWS offices.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  05/0300Z 41.2N  68.7W   65 KT  75 MPH
  12H  05/1200Z 44.0N  66.0W   60 KT  70 MPH...POST-TROP/EXTRATROP
  24H  06/0000Z 46.5N  63.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
  36H  06/1200Z 48.5N  59.3W   40 KT  45 MPH...POST-TROP/EXTRATROP
  48H  07/0000Z 51.5N  55.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
  72H  08/0000Z 58.0N  51.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
  96H  09/0000Z 60.0N  49.0W   30 KT  35 MPH...POST-TROP/EXTRATROP
 120H  10/0000Z 61.5N  44.5W   25 KT  30 MPH...POST-TROP/EXTRATROP
 
 $$
 Forecaster Beven