066 
 WTNT42 KNHC 292044
 TCDAT2
 
 HURRICANE GASTON DISCUSSION NUMBER  29
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016
 500 PM AST MON AUG 29 2016
 
 Gaston's satellite presentation continues to slowly degrade, with
 the latest microwave data suggesting it could be undergoing an
 eyewall replacement.  The initial wind speed is lowered to 90 kt in
 accordance with the latest satellite estimates.  Little change in
 intensity is expected for the next couple of days while Gaston
 remains over warm waters with light-to-moderate shear, although the
 eyewall cycle adds a wrinkle to the forecast.  In a couple of days,
 a gradual increase in shear, along with a decrease in SSTs, should
 cause a more significant weakening. Intensity guidance is a bit
 lower than 6 hours ago, and the latest NHC intensity forecast
 follows that trend.
 
 Gaston appears to be moving a bit faster, now north-northeastward at
 3 kt. Due to a ridge becoming established to the southeast of the
 cyclone, Gaston should accelerate to the east-northeast over the
 next few days.  The end of the forecast is tricky, with some
 uncertainties over how Gaston interacts with the mid-latitude
 westerlies and the strength of an eastern Atlantic ridge.  While
 the overall guidance suite has shifted somewhat to the north at days
 4 and 5, the ECMWF has been more consistent during the past few
 days and has stayed farther south.  Thus, the new forecast is on
 the southern side of the guidance envelope, to the south of the
 model consensus at long range.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  29/2100Z 31.2N  55.2W   90 KT 105 MPH
  12H  30/0600Z 31.6N  54.5W   90 KT 105 MPH
  24H  30/1800Z 32.2N  52.8W   85 KT 100 MPH
  36H  31/0600Z 33.2N  50.7W   85 KT 100 MPH
  48H  31/1800Z 34.6N  48.0W   85 KT 100 MPH
  72H  01/1800Z 37.7N  39.6W   75 KT  85 MPH
  96H  02/1800Z 38.5N  32.0W   55 KT  65 MPH
 120H  03/1800Z 40.0N  28.0W   40 KT  45 MPH
 
 $$
 Forecaster Blake