WTPA43 PHFO 190243 TCDCP3 TROPICAL DEPRESSION TWO-C DISCUSSION NUMBER 1 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP022006 500 PM HST MON SEP 18 2006 THAT AREA OF DISTURBED WEATHER WELL TO THE SOUTH OF THE ISLANDS WE HAVE BEEN WATCHING FOR DAYS HAS FINALLY GOTTEN ORGANIZED ENOUGH TO BE CLASSIFIED AS A TROPICAL DEPRESSION...THE SECOND ONE OF THE SEASON HERE IN THE CENTRAL PACIFIC. THE CONVECTION THAT FLARED LATE LAST NIGHT HAS DIMINISHED SOME TODAY...BUT FROM A MORNING QUICKSCAT PASS IT APPEARS AS THOUGH A DECENT SURFACE CIRCULATION IS IN PLACE. IN FACT QUICKSCAT DATA INDICATED A QUITE A FEW 35KT...ALBEIT RAIN FLAGGED...WIND BARBS AROUND THE CIRCULATION. WITH THE DEMISE OF CONVECTION SOME TODAY AND THE POORER LOOK ON SATELLITE...WILL START TD-2C AT A POTENTIALLY QUITE CONSERVATIVE 25KT. TD-2C IS IN A SIMILAR AREA TO WHERE IOKE GOT ITS BIRTH...AND THE OVERALL SYNOPTIC CONDITIONS LOOK SIMILAR. VERY WARM WATER AND UPPER LEVEL SHEAR VALUES LESS THAN 10KT. CIRRUS FROM THE SYSTEM SHOW DECENT UPPER LEVEL OUTFLOW CHANNELS TO THE NORTH OF THE SYSTEM. ONLY NEGATIVE IS THAT THERE IS STILL A CONSIDERABLE AMOUNT OF ITCZ CONVECTION WITHIN 10 DEGREES SOUTHWEST OF THE SYSTEM. SUBSIDENCE AROUND THAT CONVECTION MAY BE HAMPERING TD-2C DEVELOPMENT. SOME MIXED SIGNALS WITH THE NEAR TERM FUTURE OF TD-2C ESPECIALLY WITH INTENSITY. LATEST GUIDANCE SUITE IS NOT AS GUNG-HO ON DEVELOPING IT MUCH FOR THE NEXT 48HRS...PERHAPS THIS IS DUE TO ITS PULSE DOWNWARD THIS MORNING. SURPRISINGLY EVEN THE GFDL...WHICH ACCURATELY PORTRAYED THE RAPID SPIN UP OF IOKE...IS LESS THAN ENTHUSIASTIC WITH TD-2C THRU 60HRS. IT KEEPS IT AS A TD/WEAK TS BEFORE FINALLY STRENGTHENING IT TO A STRONG TS THEN HURRICANE AFTER 96HRS. SHIPS GUIDANCE STEADILY STRENGTHENS IT TO TS IN 18HRS THEN TO MINIMAL HURRICANE IN 60HRS. SHOULD BE NOTED THAT EARLIER SHIPS GUIDANCE WAS SHOWING A 60 TO 80% LIKELIHOOD OF RAPID INTENSIFICATION (25KT INCREASE WITHIN 24HRS) BUT THE 00Z SHIPS WAS DOWN TO 36% CHANCE DUE TO THE LACK OF DEEP CONVECTION. DUE TO CONVECTION STILL WITH ITCZ...HAVE GIVEN CREDENCE TO A SLIGHTLY SLOWER START TO TD-2C. EXPECT IT TO CUT THE UMBILICAL CORD TO THE ITCZ TOMORROW AND AT THAT TIME WILL BE ABLE TO DEVELOP QUITE QUICKLY. WILL PROJECT HURRICANE STRENGTH IN 48 HRS. IF IT CAN NOT GET AWAY FROM THE ITCZ...IT MAY NOT HAVE MUCH OF A LIFE. AFTER THAT MAKE OR BREAK TIME...GLOBAL MODELS SHOW UPPER LEVEL RIDGING BUILDING IN ACROSS 15N BETWEEN 160W AND 175W AND MAKING FOR A LOW SHEAR ENVIRONMENT. SORTA LIKE WHAT WE HAD WITH IOKE...SO DONT SEE ANY REASON FOR THE STORM TO NOT TO CONTINUE INTENSIFYING HOWEVER I DONT HAVE ENOUGH CONFIDENCE TO BE FORECASTING A MAJOR HURRICANE THIS EARLY OUT. AS A RESULT THE INTENSITY FORECAST IS CLOSE TO THE GFDL AND A LITTLE WEAKER THAN SHIPS THRU 24HRS...THEN CLOSE TO SHIPS IN THE MID TERM AND THEN SOMEWHAT ABOVE ALL GUIDANCE AFTER 72HRS. TRACK-WISE...MUCH MORE CONSISTENCY WITH VARIOUS MODELS...GENERALLY A WNW TRACK THRU THE PERIOD. DID SLOW THE FORWARD SPEED DOWN AT DAYS 4 AND 5 AS THE EXPECTED HURRICANE IS EXPECTED TO BE IN A LIGHTER STEERING FLOW DUE TO THE RIDGE OF HIGH PRESSURE. ON THE PROJECTED COURSE...THE SYSTEM WOULD PASS SAFELY OVER 200 MILES SOUTH OF JOHNSTON ATOLL LATE THURSDAY. HOWEVER INTERESTS AROUND JOHNSTON SHOULD PAY ATTENTION TO LATER FORECASTS FROM CPHC. FOR WHAT IT MATTERS...IF TD-2C CAN ACHIEVE 35KTS IT WILL BE NAMED KIKA (KEE-KAH)...EMPHASIS ON FIRST SYLLABLE. THERE ARE A COUPLE OF MEANINGS FOR THIS WORD...AS A NOUN IT MEANS A SMALL OPELU FISH AND AS A VERB ONE MEANING IS STRONG AND ENERGETIC. THE VERB FORM IS THE ONE THAT WOULD BE MOST FITTING...ESPECIALLY IF IT DECIDES TO BECOME A HURRICANE. FORECAST POSITIONS AND MAX WINDS INITIAL 19/0300Z 10.0N 157.2W 25 KT 12HR VT 19/1200Z 10.4N 159.2W 30 KT 24HR VT 20/0000Z 10.7N 161.2W 40 KT 36HR VT 20/1200Z 11.2N 163.2W 55 KT 48HR VT 21/0000Z 11.9N 165.1W 65 KT 72HR VT 22/0000Z 13.7N 168.6W 75 KT 96HR VT 23/0000Z 15.3N 172.3W 80 KT 120HR VT 24/0000Z 16.4N 175.3W 80 KT $$ FORECASTER NASH