000
WTPZ45 KNHC 090243
TCDEP5
TROPICAL STORM LINDA DISCUSSION NUMBER   8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP152009
800 PM PDT TUE SEP 08 2009

THE OVERALL APPEARANCE OF LINDA IS STILL SOMEWHAT RAGGED THIS
EVENING.  HOWEVER...THE CENTRAL CONVECTION HAS BECOME A LITTLE
BETTER ORGANIZED WITH AN INCREASE IN BANDING NEAR THE CENTER. 
SATELLITE INTENSITY ESTIMATES FROM TAFB AND SAB HAVE INCREASED TO
55 KT...AND THERE ARE SEVERAL AMSU ESTIMATES OF 55-65 KT.  THUS...
THE INITIAL INTENSITY IS INCREASED TO 55 KT.  THE CIRRUS OUTFLOW IS
FAIR TO THE NORTH AND SOUTH AND POOR ELSEWHERE.

THE INITIAL MOTION REMAINS SLOW AT 330/2.  LINDA IS SOUTH OF A
STRONG LOW-LEVEL RIDGE...AND WITHIN A WEAKNESS IN THE
MID/UPPER-LEVEL SUBTROPICAL RIDGE.  WATER VAPOR IMAGERY SHOWS AN
UPPER-LEVEL LOW NEAR 34N127W WITH A TROUGH EXTENDING TO 22N140W. 
THE LARGE-SCALE MODELS FORECAST THIS TROUGH TO WEAKEN THE
SUBTROPICAL RIDGE WEST OF LINDA AND ALLOW THE CYCLONE TO MOVE
FASTER TOWARD THE NORTH-NORTHWEST.  THE TRACK GUIDANCE IS IN FAIR
AGREEMENT THROUGH THE FIRST 48-72 HR...AND THE NEW FORECAST TRACK
IS AN UPDATE OF THE PREVIOUS FORECAST THROUGH 72 HR.  AFTER THAT...
THE GUIDANCE DIVERGES AS TO WHERE THE WEAKENING LOW-LEVEL CENTER OF
LINDA WILL GO AS THE CYCLONE SHEARS APART OVER COLDER SEA SURFACE
TEMPERATURES.  THE HWRF...GFS...AND THE BAM MODELS FORECAST LINDA
TO TURN NORTHWARD OR NORTHEASTWARD...WHILE THE UKMET...ECMWF...AND
THE CANADIAN CALL FOR A WESTWARD TURN.  THE NEW FORECAST CALLS FOR
A NORTHWARD TURN IN AGREEMENT WITH THE GFS AND HWRF...BUT AT A
SLOWER FORWARD SPEED THAN THE PREVIOUS FORECAST DUE TO THE OVERALL
SPREAD IN THE GUIDANCE AT 96 AND 120 HR.

LINDA IS CURRENTLY IN AN ENVIRONMENT OF LIGHT SOUTHWESTERLY VERTICAL
WIND SHEAR.  WATER VAPOR IMAGERY SHOWS VERY DRY UPPER-LEVEL AIR
JUST WEST OF THE CYCLONE...AND SOME OF THIS AIR MAY BE ENTRAINING
INTO THE CIRCULATION.  THIS COULD BE SLOWING THE DEVELOPMENT IN AN
OTHERWISE FAVORABLE ENVIRONMENT.  THE GFDL AND HWRF CONTINUE TO
FORECAST LINDA TO BECOME A HURRICANE IN 24 HR...AND THE OTHER
INTENSITY GUIDANCE FORECASTS SOME STRENGTHENING.  BASED ON THIS...
THE INTENSITY FORECAST SHOWS MODEST STRENGTHENING IN THE FIRST
12-24 HR.  AFTER THAT...THE CYCLONE SHOULD ENCOUNTER COOLER SSTS AND
INCREASING SHEAR...WHICH SHOULD CAUSE STEADY WEAKENING.  LINDA IS
FORECAST TO WEAKEN TO A DEPRESSION IN ABOUT 72 HR...AND TO A
REMNANT LOW IN ABOUT 96 HR.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      09/0300Z 15.6N 128.4W    55 KT
 12HR VT     09/1200Z 16.1N 128.7W    60 KT
 24HR VT     10/0000Z 17.2N 129.3W    60 KT
 36HR VT     10/1200Z 18.5N 130.1W    55 KT
 48HR VT     11/0000Z 19.8N 130.8W    45 KT
 72HR VT     12/0000Z 22.0N 132.0W    30 KT
 96HR VT     13/0000Z 23.5N 132.5W    20 KT...REMNANT LOW
120HR VT     14/0000Z 25.0N 132.0W    20 KT...REMNANT LOW
 
$$
FORECASTER BEVEN