000 WTPZ42 KNHC 280231 TCDEP2 TROPICAL STORM BORIS DISCUSSION NUMBER 4 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP022008 800 PM PDT FRI JUN 27 2008 BORIS' CLOUD PATTERN HAS NOT CHANGED APPRECIABLY OVER THE PAST SEVERAL HOURS. THE SYSTEM CONTINUES TO PRODUCE VERY COLD...-80 DEG C...CLOUD TOPS AND THERE ARE SOME BANDING FEATURES EVIDENT OVER THE SOUTHERN AND WESTERN PORTIONS OF THE CIRCULATION. DVORAK INTENSITY ESTIMATES REMAIN AT 45 KT AND SO DOES THE OFFICIAL INITIAL INTENSITY. THERE IS FAIRLY PRONOUNCED UPPER-LEVEL OUTFLOW OVER ALL BUT THE NORTHEASTERN QUADRANT OF THE CYCLONE. SOME MODEST STRENGTHENING IS FORECAST TO OCCUR WITHIN THE NEXT 12 TO 24 HOURS. AFTERWARDS...HOWEVER...DYNAMICAL GUIDANCE INDICATES THAT EASTERLY SHEAR WILL INCREASE OVER BORIS AS A RESULT OF AN INVERTED UPPER-LEVEL TROUGH APPROACHING FROM THE EAST. THE OFFICIAL INTENSITY FORECAST IS SLIGHTLY LOWER THAN THAT FROM THE PREVIOUS ADVISORY AND IS IN REASONABLE AGREEMENT WITH THE LATEST SHIPS OUTPUT. INITIAL MOTION IS ESTIMATED TO BE 305/9. THERE HAS BEEN LITTLE CHANGE IN THE TRACK FORECAST REASONING FROM THE PREVIOUS ADVISORY. A MID-TROPOSPHERIC RIDGE IS FORECAST BY THE GLOBAL MODELS TO BUILD TO THE NORTH OF THE TROPICAL CYCLONE. THIS SHOULD FORCE A TURN TOWARD THE WEST WITHIN 36 TO 48 HOURS. THE OFFICIAL FORECAST IS ROUGHLY IN THE MIDDLE OF THE GUIDANCE SUITE AND CLOSE TO THE GFDL TRACK. THIS IS VERY SIMILAR TO THE TRACK FROM THE PREVIOUS PACKAGE. FORECAST POSITIONS AND MAX WINDS INITIAL 28/0300Z 13.6N 110.8W 45 KT 12HR VT 28/1200Z 14.0N 111.9W 50 KT 24HR VT 29/0000Z 14.4N 113.0W 55 KT 36HR VT 29/1200Z 14.5N 114.3W 55 KT 48HR VT 30/0000Z 14.5N 115.5W 50 KT 72HR VT 01/0000Z 14.5N 118.5W 45 KT 96HR VT 02/0000Z 14.5N 122.0W 35 KT 120HR VT 03/0000Z 14.5N 125.5W 30 KT $$ FORECASTER PASCH