Tropical Depression SEVEN-E

ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
 
TROPICAL DEPRESSION SEVEN-E DISCUSSION NUMBER   2
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP072011
800 PM PDT TUE AUG 16 2011
 
THE SATELLITE PRESENTATION OF THE DEPRESSION HAS CHANGED LITTLE
SINCE THIS AFTERNOON.  DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB
REMAIN UNCHANGED...AND THE INITIAL INTENSITY IS HELD AT 30 KT. 
THE DEPRESSION WILL BE TRAVERSING SOME OF THE WARMEST WATERS IN THE
EASTERN PACIFIC OVER THE NEXT DAY OR TWO.  DURING THE NEXT 12-24
HOURS THE STRONG UPPER-LEVEL EASTERLY WINDS OVER THE SYSTEM ARE
FORECAST TO DECREASE...WHICH SHOULD RESULT IN AN ENVIRONMENT
FAVORABLE FOR STRENGTHENING.  THERE REMAINS SOME DIFFERENCES
IN THE FORECAST STRENGTH OF THE CYCLONE IN 2-3 DAYS FROM THE
VARIOUS INTENSITY MODELS.  THE SHIPS AND GFDL MODELS ARE HIGHER
THAN THE LGEM AND HWRF...AND SHOW THE DEPRESSION BECOMING A
HURRICANE IN A COUPLE OF DAYS.  GIVEN THE EXPECTED FAVORABLE
CONDITIONS...THE NHC FORECAST LEANS TOWARD THE HIGHER SHIPS/GFDL
GUIDANCE...BUT REMAINS SOMEWHAT MORE CONSERVATIVE.

THE CENTER HAS BEEN VERY DIFFICULT TO LOCATE IN CONVENTIONAL
SATELLITE IMAGERY...HOWEVER A TIMELY 0003 UTC SSMIS MICROWAVE IMAGE
SUGGESTS THAT THE CENTER IS LOCATED JUST TO THE EAST OF THE DEEP
CONVECTION...AND A LITTLE NORTH OF THE PREVIOUS ESTIMATES.  THE
INITIAL MOTION IS A RATHER UNCERTAIN 295/12.  A STRONG MID-LEVEL
RIDGE TO THE NORTH OF THE CYCLONE IS EXPECTED TO KEEP IT MOVING ON
A WEST-NORTHWESTWARD HEADING DURING THE ENTIRE FORECAST PERIOD. 
GLOBAL MODELS SUGGEST THAT THE RIDGE WILL WEAKEN BY DAYS 4 AND
5...WHICH SHOULD RESULT IN THE SYSTEM SLOWING DOWN.  THE TRACK
GUIDANCE IS IN GOOD AGREEMENT THROUGH 3-4 DAYS...WITH SOME
DIVERGENCE THEREAFTER.  THE OFFICIAL FORECAST IS SOUTH OF THE TVCE
MODEL CONSENSUS AND IS IN BEST AGREEMENT WITH THE ECMWF AND GFS. 
THE NEW TRACK IS A LITTLE NORTH OF THE PREVIOUS FORECAST DUE TO THE
SLIGHT NORTHWARD RELOCATION OF THE CENTER.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  17/0300Z 15.0N 100.8W   30 KT  35 MPH
 12H  17/1200Z 15.6N 102.8W   40 KT  45 MPH
 24H  18/0000Z 16.4N 105.9W   50 KT  60 MPH
 36H  18/1200Z 17.1N 108.7W   60 KT  70 MPH
 48H  19/0000Z 17.8N 111.2W   70 KT  80 MPH
 72H  20/0000Z 18.9N 115.0W   75 KT  85 MPH
 96H  21/0000Z 19.8N 117.5W   60 KT  70 MPH
120H  22/0000Z 20.5N 119.5W   45 KT  50 MPH
 
$$
FORECASTER BROWN
 
NNNN