768 
 WTNT43 KNHC 070848
 TCDAT3
 
 Tropical Storm Leslie Discussion Number  44
 NWS National Hurricane Center Miami FL       AL132018
 500 AM AST Sun Oct 07 2018
 
 Leslie has not changed much overnight.  The storm has several curved
 bands to the east and north of the center, but a limited amount
 of deep convection in the southwestern quadrant.  The initial
 intensity is held at 50 kt based on the steady state appearance
 since the previous ASCAT pass. This estimate is also in fair
 agreement with the latest Dvorak estimates from TAFB and SAB.
 Leslie will likely fluctuate in strength during the next several
 days, but it should remain a tropical storm through the forecast
 period. Although some weakening is possible during the next day or
 so due to cool 23 to 24 deg C waters, slight re-strengthening is
 likely after that time when the system moves back over warmer waters
 and remains in relatively low wind shear conditions.  There could be
 some increase in shear by the end of the forecast period, however,
 which could result in slight weakening again.  The models are in
 fairly good agreement, and the NHC intensity forecast is close to
 the IVCN and HCCA consensus models.
 
 Leslie is moving eastward at 10 kt within the mid-latitude westerly
 flow on the south side of a broad mid- to upper-level trough.  This
 trough is expected to amplify some, which should cause the storm to
 move east-southeastward at a faster pace during the next few days.
 A slight turn back to the east or east-northeast with a decrease
 in forward speed is likely by the end of the forecast period when
 the trough weakens.   There is a significant amount of spread in
 the models associated with differences on how fast they expect
 Leslie to move.  In fact, the GFS and ECMWF models are more than
 1000 n mi apart by day 5.  The NHC track forecast is a little slower
 than the previous one at the end of the period to come in better
 agreement with the latest consensus aids.  Given the model spread,
 the confidence in the long-range track forecast is low at this
 time.
 
 Large swells generated by Leslie are expected to continue through
 tonight across the northeastern coast of the United States, Bermuda,
 the Greater and Lesser Antilles, and Atlantic Canada. Please
 consult products from your local weather office as these conditions
 could cause life-threatening surf and rip currents.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  07/0900Z 37.2N  52.0W   50 KT  60 MPH
  12H  07/1800Z 36.6N  50.3W   45 KT  50 MPH
  24H  08/0600Z 36.1N  48.0W   45 KT  50 MPH
  36H  08/1800Z 35.1N  45.1W   50 KT  60 MPH
  48H  09/0600Z 33.7N  42.2W   55 KT  65 MPH
  72H  10/0600Z 30.1N  36.0W   55 KT  65 MPH
  96H  11/0600Z 28.6N  32.0W   55 KT  65 MPH
 120H  12/0600Z 29.5N  27.2W   50 KT  60 MPH
 
 $$
 Forecaster Cangialosi
 
 

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