WTPA41 PHFO 190852
TCDCP1

TROPICAL DEPRESSION COSME DISCUSSION NUMBER  20
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP062007
1100 PM HST WED JUL 18 2007

COSME IS STILL SHOWING SIGNS OF LIFE.
 
OVER THE PAST 6 HOURS AN AREA OF COLD CLOUDS ON THE SOUTHEAST SIDE
OF COSME HAS EXPANDED AND COVERED THE CENTER. THAT MADE IT MORE
DIFFICULT TO PINPOINT THE CENTER ON CONVENTIONAL INFRARED
IMAGERY...BUT MICROWAVE IMAGERY FROM A 0513 DMSP PASS SHOWED THE
CENTER NICELY. THESE DATA CAME IN AFTER WE REQUESTED THE FORECAST
GUIDANCE SO WE SHIFTED THE 0600 UTC POSITION TO MATCH THE LOCATION
FROM THE MICROWAVE PASS. THERE WAS ALSO A NICE QUIKSCAT PASS OVER
COSME AT 0316 UTC. THE QUICKSCAT SHOWED 30 KT WINDS EXTENDING AS
MUCH AS 90 NM NORTHWEST OF THE CENTER.
 
A RIDGE TO THE NORTH CONTINUES TO STEER COSME TOWARD THE WEST
NORTHWEST AND THE INITIAL MOTION IS 280 DEGREES AT 13 KT...VERY
LITTLE CHANGE FROM THE PREVIOUS MOVEMENT. THE MODELS REMAIN
CONSISTENT IN CONTINUING THE WEST NORTHWEST MOTION AND WE HAVE MADE
NO CHANGES TO THE FORECAST TRACK. 

WHILE THE TRACK HAS BEEN VERY CONSISTENT...FORECASTING THE INTENSITY
REMAINS MORE UNCERTAIN. COSME CONTINUES TO MOVE OVER FAIRLY COOL
WATER...ABOUT 77 DEGREES FAHRENHEIT...BUT THE SYSTEM HAS SHOWN
SIGNS OF INTENSIFICATION.  THE LATEST CIMSS VERTICAL PRODUCT SHOWED
FAVORABLE SHEAR VALUES FOR THE FIRST 6 HOURS...THEN A RETURN TO
NEUTRAL VALUES. WE KEPT THE INITIAL INTENSITY UNCHANGED AT 30 KT...
BUT IF THE CONVECTION NEAR THE CENTER PERSISTS OVER THE NEXT SIX
HOURS IT IS LIKELY WE WOULD TAKE COSME BACK UP TO TROPICAL STORM
INTENSITY ON THE NEXT BULLETIN. COSME SHOULD REMAIN OVER RELATIVELY
COOL WATER WITH FAIRLY LOW SHEAR OVER THE NEXT 48 HOURS...SO IF THE
SYSTEM DOES LOSE ALL IT/S CONVECTION DURING THAT PERIOD...IT MAY
WELL BECOME TOO WEAK TO HAVE MUCH CHANCE TO RE-INTENSIFY. IF COSME
MANAGES TO KEEP SOME CONVECTION WHEN IT MOVES WEST OF 155W...IT
WILL START MOVING BACK OVER WARMER WATER. IF SHEAR REMAINS WEAK
ENOUGH AT THAT POINT...COSME MIGHT WELL RE-INTENSIFY. THESE
UNCERTAINTIES KEEP OUR CONFIDENCE IN THE INTENSITY FORECAST RATHER
LOW.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      19/0900Z 15.4N 142.7W    30 KT
 12HR VT     19/1800Z 15.9N 144.9W    30 KT
 24HR VT     20/0600Z 16.4N 147.9W    30 KT
 36HR VT     20/1800Z 17.0N 151.0W    30 KT
 48HR VT     21/0600Z 17.5N 154.1W    30 KT
 72HR VT     22/0600Z 18.1N 160.2W    30 KT
 96HR VT     23/0600Z 18.4N 166.1W    25 KT
120HR VT     24/0600Z 18.4N 171.8W    20 KT...DISSIPATING
 
$$
FORECASTER HOUSTON/DONALDSON