000
WTPZ42 KNHC 180252
TCDEP2
TROPICAL STORM FAUSTO DISCUSSION NUMBER   8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP072008
800 PM PDT THU JUL 17 2008
 
A 2121Z AMSR-E OVERPASS INDICATED THAT FAUSTO IS DEVELOPING A
TIGHTLY COILED BANDING EYE FEATURE OVER THE SOUTH SEMICIRCLE.
ADDITIONALLY...THE MAJORITY OF THE STRONGER RAIN BANDS ARE LOCATED
OVER THE SOUTHERN PERIPHERY OF THE SYSTEM.  THE INITIAL INTENSITY IS
A COMPROMISE OF THE SATELLITE INTENSITY ESTIMATES AND IS SET AT 60
KT. THE OFFICIAL INTENSITY FORECAST IS A BLEND OF THE SHIPS AND THE
GFDL...AND CALLS FOR GRADUAL STRENGTHENING THROUGH THE NEXT 72
HOURS. AFTERWARD...GRADUAL WEAKENING IS FORECAST.
 
SUPPORTED BY THE TWO PREVIOUS MICROWAVE IMAGES...THE INITIAL MOTION
IS ESTIMATED AT 290/10...A LITTLE SLOWER.  THE FORECAST PHILOSOPHY
IS A MIRROR IMAGE OF THE PREVIOUS PACKAGE WITH A GENERAL
WEST-NORTHWESTWARD MOTION THROUGH THE ENTIRE FORECAST PERIOD. IT
APPEARS THAT FAUSTO'S DECREASE IN FORWARD MOTION MAY BE DUE TO A
TRANSIENT MID LEVEL PERTURBATION MOVING SOUTHWESTWARD OVER THE
NORTHWEST COAST OF MEXICO. A MAJORITY OF THE LARGE-SCALE MODELS
HAVE PICKED UP ON THIS FEATURE AND MOVE IT IN TANDEM WITH THE
TROPICAL CYCLONE OVER THE NEXT COUPLE OF DAYS.  AFTERWARD...THIS
WEAKNESS IN THE RIDGE CREATED BY THE AFOREMENTIONED TROUGH BECOMES
FURTHER ENHANCED IN RESPONSE TO A MID-LATITUDE LOW PRESSURE SYSTEM
APPROACHING THE WEST COAST OF THE U.S.  CONSEQUENTLY...THIS INITIAL
REDUCTION IN FORWARD SPEED IS EXPECTED TO PREVAIL THROUGH THE
PERIOD.  THE OFFICIAL TRACK FORECAST RESIDES CLOSELY TO A CONSENSUS
OF THE DYNAMICAL MODELS.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      18/0300Z 13.0N 105.9W    60 KT
 12HR VT     18/1200Z 13.4N 107.4W    65 KT
 24HR VT     19/0000Z 13.9N 109.1W    70 KT
 36HR VT     19/1200Z 14.5N 110.6W    70 KT
 48HR VT     20/0000Z 15.1N 111.8W    75 KT
 72HR VT     21/0000Z 16.7N 115.4W    75 KT
 96HR VT     22/0000Z 18.5N 119.5W    65 KT
120HR VT     23/0000Z 20.0N 123.5W    50 KT
 
$$
FORECASTER UNKNOWN