000
WTPZ41 KNHC 181436
TCDEP1
TROPICAL DEPRESSION ONE-E DISCUSSION NUMBER   1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP012009
800 AM PDT THU JUN 18 2009
 
SATELLITE IMAGERY INDICATES THAT THE AREA OF DISTURBED WEATHER
SOUTHWEST OF MANZANILLO HAS ACQUIRED SUFFICIENT ORGANIZATION TO BE
DESIGNATED A TROPICAL DEPRESSION...THE FIRST OF THE 2009 EAST
PACIFIC SEASON.
 
THE INITIAL MOTION ESTIMATE IS 350/08.  THE GLOBAL MODELS ARE IN
RELATIVELY GOOD AGREEMENT ON THE EVOLUTION OF THE LARGE-SCALE
PATTERN...SHOWING A MID-TO UPPER LEVEL TROUGH CUTTING OFF OVER THE
NORTHERN GULF OF CALIFORNIA TONIGHT.  THE SOUTHERLY FLOW AHEAD OF
THE UPPER LOW WILL STEER THE CYCLONE GENERALLY NORTHWARD AND
TOWARD THE PACIFIC COAST OF MEXICO OVER THE NEXT COUPLE OF DAYS.
THE OFFICIAL FORECAST IS BETWEEN THE MULTI-MODEL CONSENSUS ON THE
LEFT AND THE ECMWF ON THE RIGHT...WHICH SHOWS THE BEST DEPICTION OF
THE SYSTEM IN ITS FIELDS.
 
DVORAK T-NUMBERS AT 1200 UTC WERE 2.0 FROM BOTH TAFB AND SAB. THE
FIRST FEW VISIBLE SATELLITE IMAGES AND MICROWAVE DATA INDICATE THAT
THE CENTER IS LOCATED ON THE NORTHERN EDGE OF THE DEEP CONVECTION.
THE INITIAL INTENSITY IS SET AT 25 KT BASED ON THE LIMITED
CONVECTION NEAR THE CENTER OF THE SYSTEM. THE OFFICIAL FORECAST
SHOWS THE SYSTEM BECOMING A MINIMAL TROPICAL STORM PRIOR TO
LANDFALL...IN BEST AGREEMENT WITH THE 0000 UTC RUN OF THE GFDL.
ADDITIONALLY...THE INTENSITY PROBABILITY PRODUCT SHOWS THAT THERE IS
A 33 PERCENT CHANCE OF THE CYCLONE BEING A TROPICAL STORM BY FRIDAY
AFTERNOON.  AFTER LANDFALL...THE CYCLONE WILL QUICKLY WEAKEN AND
DISSIPATE OVER THE MOUNTAINOUS TERRAIN OF MEXICO.
 
THE FORECAST TRACK AND INTENSITY REQUIRE THE ISSUANCE OF A TROPICAL
STORM WATCH AT THIS TIME FOR A PORTION OF THE PACIFIC COAST OF
MAINLAND MEXICO AND LAS ISLAS MARIAS.  RAINFALL ASSOCIATED WITH THE
DEPRESSION MAY IMPACT THE PACIFIC COAST OF MEXICO SOUTH OF THE WATCH
AREA WELL BEFORE THE SYSTEM REACHES THE COAST.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      18/1500Z 18.2N 108.5W    25 KT
 12HR VT     19/0000Z 19.8N 108.5W    25 KT
 24HR VT     19/1200Z 21.5N 108.0W    30 KT
 36HR VT     20/0000Z 23.1N 107.5W    35 KT
 48HR VT     20/1200Z 24.9N 107.0W    25 KT...INLAND
 72HR VT     21/1200Z...DISSIPATED
 
$$
FORECASTER BRENNAN/BERG