000
WTPZ45 KNHC 152033
TCDEP5
TROPICAL STORM DOLORES DISCUSSION NUMBER   4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP052009
200 PM PDT WED JUL 15 2009
 
VISIBLE IMAGERY INDICATES THAT DOLORES' CIRCULATION CENTER IS
PARTIALLY DISPLACED TO THE SOUTHWEST OF THE CONVECTIVE CANOPY...AS
SOUTHWESTERLY SHEAR ASSOCIATED WITH AN UPPER TROUGH LOCATED TO THE
NORTHWEST OF THE CYCLONE CONTINUES TO AFFECT THE CLOUD PATTERN.
ALTHOUGH DOLORES HAS BEEN AFFECTED BY THE UPPER TROUGH THIS
AFTERNOON...THE CONVECTIVE BAND HAS BECOME A LITTLE BETTER
ORGANIZED...AS REFLECTED BY THE DVORAK INTENSITY ESTIMATES.
THEREFORE...THE INITIAL INTENSITY IS INCREASED TO 40 KT.
 
SOME FURTHER STRENGTHENING IS EXPECTED DURING THE NEXT 24 HOURS
DESPITE THE RATHER MARGINAL UPPER-LEVEL WIND PATTERN.
AFTERWARD...A GRADUAL WEAKENING IS FORECAST AS DOLORES MOVES OVER
COOLER SEA SURFACE TEMPERATURES...ULTIMATELY BEING REDUCED TO A
SWIRL OF LOW CLOUDS IN ABOUT 72 HOURS. IT SHOULD BE NOTED THAT
DOLORES COULD BECOME A BIT STRONGER EARLY IN THE PERIOD THAN
INDICATED BY THE OFFICIAL FORECAST IF THE UPPER TROUGH WEAKENS AND
LIFTS NORTHEASTWARD SOONER THAN INDICATED BY THE DYNAMICAL MODELS.
 
INITIAL MOTION IS ESTIMATED AT 310/12. THE TROPICAL CYCLONE IS
MOVING WITHIN THE SOUTHWESTERN EXTENT OF A MID-LEVEL SUBTROPICAL
RIDGE THAT EXTENDS WESTWARD ACROSS THE NORTHEAST PACIFIC FROM
NORTHERN MEXICO. WITHIN THE NEXT 24 HOURS...A GRADUAL TURN MORE
TOWARD THE WEST-NORTHWEST IS EXPECTED...FOLLOWED BY A GENERALLY
WESTWARD MOTION WITHIN THE SHALLOW EASTERLY FLOW AS THE DOLORES
WEAKENS. THE OFFICIAL FORECAST IS SHIFTED SLIGHTLY TO THE RIGHT OF
THIS MORNING'S FORECAST AND CLOSELY FOLLOWS THE DYNAMICAL MODEL
CONSENSUS.
 
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      15/2100Z 16.2N 116.6W    40 KT
 12HR VT     16/0600Z 17.1N 118.3W    45 KT
 24HR VT     16/1800Z 18.4N 121.0W    45 KT
 36HR VT     17/0600Z 19.6N 124.0W    40 KT
 48HR VT     17/1800Z 20.5N 127.0W    35 KT
 72HR VT     18/1800Z 21.5N 133.0W    25 KT...REMNANT LOW
 96HR VT     19/1800Z 22.0N 139.0W    25 KT...REMNANT LOW
120HR VT     20/1800Z 22.0N 144.5W    20 KT...REMNANT LOW
 
$$
FORECASTER ROBERTS/BRENNAN