000
WTPZ43 KNHC 032031
TCDEP3
 
TROPICAL STORM SONIA DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP182013
100 PM PST SUN NOV 03 2013
 
SONIA HAS CHANGED LITTLE IN ORGANIZATION SINCE THIS MORNING.
VISIBLE SATELLITE PICTURES SHOW THAT THE CENTER REMAINS NEAR THE
SOUTHEASTERN EDGE OF THE DEEP CONVECTION...HOWEVER THE IMAGERY
SUGGESTS THAT THE CIRCULATION MAY BE BECOMING ELONGATED IN A
NORTHEAST TO SOUTHWEST ORIENTATION.  SUBJECTIVE AND OBJECTIVE
SATELLITE INTENSITY ESTIMATES ARE UNCHANGED AND THE INITIAL
INTENSITY REMAINS 40 KT FOR THIS ADVISORY.  IT APPEARS THAT SONIA
HAS REACHED ITS PEAK INTENSITY SINCE SOUTHWESTERLY SHEAR IS EXPECTED
TO INCREASE SIGNIFICANTLY DURING THE NEXT 12 TO 18 HOURS.  THIS IS
LIKELY TO CAUSE SOME SLIGHT WEAKENING BEFORE SONIA MAKES LANDFALL.
RAPID WEAKENING WILL OCCUR AFTER LANDFALL AND SONIA IS FORECAST TO
DISSIPATE OVER THE MOUNTAINS OF WESTERN MEXICO BY TUESDAY EVENING.
 
SONIA HAS TURNED NORTH-NORTHEASTWARD AND BEGUN TO ACCELERATE...WITH 
AN INITIAL MOTION OF 015/12 KT.  THE CYCLONE IS FORECAST TO MOVE
NORTH-NORTHEASTWARD DURING THE NEXT 24 HOURS...AHEAD OF A MID- TO
UPPER-LEVEL TROUGH THAT IS MOVING INTO THE SOUTHWESTERN UNITED
STATES AND NORTHERN MEXICO.  THE TRACK GUIDANCE REMAINS IN GOOD
AGREEMENT AND THE NHC FORECAST IS AGAIN ESSENTIALLY AN UPDATE OF
THE PREVIOUS ADVISORY.

THE PRIMARY THREAT FROM SONIA IS LOCALLY HEAVY RAINFALL THAT IS
EXPECTED TO OCCUR DURING THE NEXT DAY OR SO OVER PORTIONS OF 
WESTERN MAINLAND MEXICO.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  03/2100Z 21.4N 109.1W   40 KT  45 MPH
 12H  04/0600Z 23.3N 108.0W   35 KT  40 MPH
 24H  04/1800Z 25.3N 106.7W   25 KT  30 MPH...INLAND
 36H  05/0600Z...DISSIPATED
 
$$
FORECASTER BROWN