WTPA41 PHFO 202059
TCDCP1

TROPICAL STORM OMEKA DISCUSSION NUMBER   3
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP012010
1100 AM HST MON DEC 20 2010

SATELLITE IMAGERY INDICATES SHEAR IS TAKING AN INCREASING TOLL ON 
OMEKA. INFRARED AND THE FIRST COUPLE OF VISIBLE IMAGES INDICATE THE 
LOW LEVEL CIRCULATION CENTER IS EXPOSED TO THE SOUTHWEST OF THE MAIN 
CONVECTION. SAB AND HFO DVORAK FIXES BOTH CAME IN AT 2.5 AND THE 
INITIAL INTENSITY IS THEREFORE LOWERED TO A MINIMAL TROPICAL STORM 
AT 35 KT. THE INITIAL POSITION AGREES WITH THE HFO FIX AND LIES 
SLIGHTLY TO THE NORTH OF SAB AND JTWC FIXES. OMEKA HAS SPED UP 
SLIGHTLY OVER LAST 6 HOURS AND IS MOVING TOWARD THE NORTH NORTHEAST 
AT 18 KTS.

THE MID AND UPPER LEVEL LOW PROVIDING WEST TO SOUTHWESTERLY SHEAR
ACROSS OMEKA IS CURRENTLY LOCATED NEAR 31N AND 175E. THIS LOW IS
EXPECTED TO SHIFT SLIGHTLY WESTWARD OVER THE NEXT 24 HOURS AND
MERGE WITH ANOTHER UPPER LOW DROPPING IN FROM THE NORTHWEST. GIVEN
THE NORTH NORTHEAST MOTION OF OMEKA...SHEAR VALUES ARE EXPECTED TO
CHANGE LITTLE OVER THE NEXT 24 TO 36 HOURS. THE FAST MOTION TAKES
OMEKA OVER INCREASING COOLER SSTS AS WELL AND THE LATEST FORECAST
TAKES OMEKA DOWN TO A TROPICAL DEPRESSION WITHIN 12 HOURS AND
FURTHER INTO A REMNANT LOW IN 36 HOURS. NEARLY ALL INTENSITY
GUIDANCE REFLECTS THIS WEAKENING TREND.

THE LATEST TRACK FORECAST WAS SHIFTED SLIGHTLY TO THE WEST OR LEFT
THE PREVIOUS AND LIES ALONG THE WESTERN HALF HALF OF THE GUIDANCE
ENVELOPE. THIS TAKES OMEKA APPROXIMATELY 30 MILES WEST OF LISIANSKI
ISLAND AT CLOSEST PASS THIS EVENING AND 125 MILES EAST SOUTHEAST OF
PEARL AND HERMES ATOLL AT CLOSEST PASS EARLY TUESDAY. GIVEN THE
DROP IN INITIAL INTENSITY AND THE FORECAST WEAKENING TREND...HAVE
DECIDED AGAINST ISSUING A TROPICAL STORM WATCH OR WARNING FOR THIS
PORTION OF THE NORTHWEST HAWAIIAN ISLANDS. OMEKA WILL NOT IMPACT
THE MAIN HAWAIIAN ISLANDS. 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      20/2100Z 23.2N 175.7W    35 KT
 12HR VT     21/0600Z 25.7N 174.6W    30 KT
 24HR VT     21/1800Z 28.9N 173.3W    30 KT
 36HR VT     22/0600Z 32.0N 172.5W    25 KT...POST-TROP/REMNT LOW
 
$$
FORECASTER TANABE