WTPA41 PHFO 221510
TCDCP1

TROPICAL DEPRESSION COSME DISCUSSION NUMBER  33
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP062007
500 AM HST SUN JUL 22 2007

COSME IS MOVING TOWARD 270 DEGREES AT ABOUT 17 KT OVER THE PACIFIC
OCEAN JUST EAST OF JOHNSTON ISLAND. THE LOW LEVEL CIRCULATION
CENTER...OR LLCC...WAS OBSCURED BY DEEP CONVECTIVE CLOUDS JUST A
FEW HOURS AGO. THE LLCC IS COMPLETELY EXPOSED NOW...AND THE CORE OF
COSME IS ONCE AGAIN DEVOID OF DEEP CONVECTION. THE LATEST UW-CIMSS
ESTIMATE OF ENVIRONMENTAL VERTICAL WIND SHEAR IN THE VICINITY OF
COSME INDICATES VALUES HAVE INCREASED TO NEARLY 30 KT FROM THE
NORTHWEST. RECENT WATER VAPOR IMAGERY AND THE GFS MODEL INDICATE
THERE IS A LARGE UPPER TROPOSPHERIC ANTICYCLONE CENTERED NEAR 19N
172W. THE FLOW BETWEEN THIS FEATURE AND A PROMINENT UPPER LEVEL LOW
IN THE VICINITY OF THE MAIN HAWAIIAN ISLANDS APPEAR TO BE CAUSING
THIS STRONG SHEAR.
 
THE SUBJECTIVE DVORAK INTENSITY ESTIMATES WERE 2.0 FROM SAB AND
PHFO...AND 1.0 FROM JTWC. THESE SATELLITE INTENSITY ESTIMATES
SUPPORT MAINTAINING THE SYSTEM AT 30 KT FOR THIS ADVISORY.
 
STEERING OF COSME WESTWARD IS BEING CONTROLLED BY DEEP LAYER MEAN
EASTERLIES SOUTH OF EXTENSIVE RIDGING NORTH OF THE SYSTEM. LATER IN
THE FORECAST PERIOD...COSME IS EXPECTED TO GRADUALLY TURN MORE
TOWARD THE WEST NORTHWEST AND SLOW DOWN AS IT REACHES THE WESTERN
PERIPHERY OF THE SUBTROPICAL RIDGE. THE LATEST PROJECTED TRACK IS
SLIGHTLY TO THE LEFT OF THE PREVIOUS FORECAST. 

THE CURRENT INTENSITY FORECAST IS VERY GENEROUS IN ASSUMING COSME
CAN SURVIVE THE STRONG SHEAR. THE FORECAST INTENSITY FOLLOWED THE
PREVIOUS PACKAGE VERY CLOSELY THROUGH ALMOST 36 HOURS. INCREASED
VALUES OF OCEANIC HEAT CONTENT...BASED ON THE MOST RECENT CIRA
ANALYSIS...WOULD BE A SIGNIFICANT POSITIVE FACTOR IN ALLOWING
FUTURE RE-INTENSIFICATION OF THIS DEPRESSION IN THE ABSENCE OF
STRONG VERTICAL SHEAR. AT THE MOMENT...IT IS ASSUMED THAT COSME
WILL BEGIN TO DISSIPATE WHEN IT REACHES THE DATELINE IN ABOUT 2
DAYS. IT SHOULD BE NOTED THAT THIS SYSTEM HAS PERSISTED AS A VIABLE
TROPICAL CYCLONE DURING THE PAST FEW DAYS DESPITE MANY THREATS TO
ITS EXISTENCE. THERE IS A SLIM CHANCE THAT COSME WILL SURVIVE WELL
BEYOND THE CURRENT FORECAST PERIOD...WHICH IS THE LATEST IN A 
SERIES OF FORECAST PACKAGES THAT PREDICTED ITS IMMINENT DEMISE.
 
THE FORECAST TRACK WILL BRING COSME VERY CLOSE TO JOHNSTON ISLAND
LATER TODAY. THEREFORE...EXPECT A GRADUAL DETERIORATION OF THE
WEATHER ON...AND SEAS AROUND...THIS SMALL ATOLL DURING THE NEXT 6 TO
12 HOURS.
 

FORECAST POSITIONS AND MAX WINDS
 
INITIAL      22/1500Z 16.5N 165.5W    30 KT
 12HR VT     23/0000Z 16.6N 168.5W    30 KT
 24HR VT     23/1200Z 16.8N 172.7W    30 KT
 36HR VT     24/0000Z 17.0N 176.7W    30 KT
 48HR VT     24/1200Z 17.5N 179.6E    25 KT...DISSIPATING
 72HR VT     25/1200Z 18.6N 175.3E    20 KT...REMNANT LOW
 
$$
FORECASTER HOUSTON