WDXS31 PGTW 110900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 19S (GOMBE) WARNING 
NR 011//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 15.2S 40.1E
   INITIAL INTENSITY: 80 KTS
   GEOGRAPHIC REFERENCE: 420 NM NORTH OF EUROPA ISLAND
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 06 KTS
   SIGNIFICANT WAVE HEIGHT: XX FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TC 19S MADE LANDFALL ALONG THE COAST OF MOZAMBIQUE AROUND THE
110000Z HOUR, JUST SOUTH OF NACALA. A RAGGED EYE HAD FORMED JUST
PRIOR TO LANDFALL BUT SUBSEQUENT ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A RAPID DETERIORATION AND DISAPPEARANCE OF THE EYE
STRUCTURE, AND WARMING CLOUD TOP TEMPERATURES. A 110219Z SSMIS
91GHZ MICROWAVE IMAGE SHOWED A VERY WELL DEFINED MICROWAVE EYE
FEATURE WITH A STRONG EYEWALL IN ALL QUADRANTS EXCEPT THE WESTERN
SIDE, WHICH WAS ERODED DUE TO LAND INTERACTION. THE INITIAL
POSITION IS ASSESSED IS BASED ON THE CENTER FIXES FROM PGTW AND
FMEE, WITH MEDIUM CONFIDENCE DUE TO THE LACK OF AN EYE FEATURE. THE
INITIAL INTENSITY OF 80 KNOTS IS ASSESSED WITH LOW CONFIDENCE DUE
TO THE LACK OF OVER LAND SATELLITE INTENSITY ESTIMATES AND IS BASED
PRIMARILY ON A STANDARD RATE OF OVER LAND WEAKENING.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED TO THE SOUTH. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: NO CURRENT ESTIMATE

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE
   VWS: 5-10 KTS
   SST: OVER LAND
   OUTFLOW: MODERATE EQUATORWARD
   OTHER FACTORS: WEAK POLEWARD OUTFLOW AND LAND INTERACTION. 

ANALYSIS CONFIDENCE:
   INITIAL POSITION: MEDIUM
   INITIAL INTENSITY: LOW
   INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING, HOWEVER THE FORECAST
FREQUENCY HAS BEEN SHIFTED TO 12-HOURLY.

FORECAST DISCUSSION: WHILE THE GENERAL TRACK OF TC 19S HAS BEEN
TOWARDS THE WEST-NORTHWEST, IT APPEARS TO HAVE TAKEN A BIT OF MORE
NORTHWESTWARD TRACK IN THE SIX HOURS SINCE LANDFALL. BUT THE
OVERALL STEERING MECHANISM, THE STRONG STR TO THE SOUTH, REMAINS
UNCHANGED AT THIS TIME AND THE SYSTEM IS  FORECAST TO TURN ONTO A
MORE WESTWARD TRACK IN THE NEAR-TERM EXTENDING THROUGH TAU 36. BY
TAU 36 THE SYSTEM WILL SLOW DOWN AS IT MOVES INTO A  COMPLEX
UPPER-LEVEL STEERING PATTERN WITH A NEAR-EQUATORIAL RIDGE (NER) TO
THE NORTHEAST COMPETING WITH THE STR TO THE SOUTH. BY TAU 48 A
BUILDING NORTH-SOUTH ORIENTED RIDGE WILL BECOME THE DOMINANT
STEERING MECHANISM AND THE REMNANTS OF TC 19S WILL TURN SHARPLY
SOUTH-SOUTHEASTWARD WHILST ACCELERATING TOWARDS THE COASTLINE. THE
SYSTEM IS EXPECTED TO REEMERGE OVER WATER SHORTLY BEFORE TAU 72,
AND EVENTUALLY WILL SLOW AND TURN SOUTHWARD BY TAU 120 AS IT ONCE
AGAIN ENCOUNTERS A WEAK STEERING PATTERN. NOW THAT THE SYSTEM IS
OVER LAND IT IS EXPECTED TO RAPIDLY WEAKEN, DOWN TO 30 KNOTS BY TAU
36. THE ENVIRONMENT IS FORECAST TO REMAIN VERY MOIST EVEN WHILE
OVER LAND, WITH MODERATE LEVELS OF OUTFLOW ALOFT, WHICH WILL
ENCOURAGE CONTINUED THUNDERSTORM ACTIVITY AND HEAVY RAINFALL FOR
THE DURATION OF THE SYSTEM BEING OVER LAND. THE REMAINS OF TC 19S
ARE EXPECTED TO REEMERGE OVER THE MOZAMBIQUE CHANNEL BY TAU 72,
ENCOUNTER WARM SSTS, LOW VWS AND STRONG POLEWARD OUTFLOW INTO THE
BASE OF A MID-LATITUDE TROUGH, AND WILL QUICKLY RECONSOLIDATE AND
INTENSIFY TO A PEAK OF 50 KNOTS BY TAU 120. THERE REMAINS A SMALL
POSSIBILITY THAT THE SYSTEM WILL TRACK FURTHER INLAND AND DISSIPATE
FULLY, BUT THIS SCENARIO IS ASSESSED AS UNLIKELY AT THIS TIME. 

MODEL DISCUSSION: THE NEW GUIDANCE PACKAGE, INCLUDING BOTH
DETERMINISTIC AND ENSEMBLE GUIDANCE, HAS NOT CHANGED SIGNIFICANTLY
FROM THE PREVIOUS. THE NAVGEM AND GALWEM SOLUTIONS CONTINUE TO SHOW
THE CIRCULATION REMAINING OVER LAND THROUGH THE FORECAST PERIOD AND
FULLY DISSIPATING. THE REMAINDER OF THE GUIDANCE PACKAGE SUPPORTS
THE JTWC FORECAST TRACK, WITH EGRR REPRESENTING THE WESTERN SIDE OF
THE ENVELOPE AND THE GFS AND GEFS ENSEMBLE MEAN REPRESENTING THE
EASTERN BOUNDARY. THE JTWC TRACK IS SLIGHTLY FURTHER WEST THAN THE
PREVIOUS RUN, BUT STILL ALONG THE EASTERN HALF OF THE ENVELOPE AND
JUST EAST OF THE CONSENSUS MEAN WITH MEDIUM CONFIDENCE. INTENSITY
GUIDANCE IS IN GOOD AGREEMENT UNTIL TAU 72 WHEN THE SYSTEM IS
FORECAST TO ONCE AGAIN EMERGE OVER WATER. THE JTWC FORECAST LIES
JUST ABOVE MEAN THROUGH TAU 72 WITH HIGH CONFIDENCE. IN THE
EXTENDED RANGE, THERE IS A LARGE SPREAD IN MODEL SOLUTIONS, WITH
THE HWRF INDICATING A PEAK OF 65 KNOTS WHILE THE GFS PEAKS AT 95
KNOTS WITH THE REMAINDER CLUSTERED BETWEEN 35-45 KNOTS. COAMPS-TC
ENSEMBLE INTENSITY GUIDANCE SUGGESTS A MODERATE PROBABILITY OF
MODERATE INTENSIFICATION AND LOW PROBABILITY OF RAPID
INTENSIFICATION AFTER TAU 96. THE JTWC EXTENDED RANGE FORECAST LIES
CLOSE TO THE CONSENSUS MEAN WITH LOW CONFIDENCE DUE TO THE VERY
WIDE SPREAD IN THE DETERMINISTIC AND ENSEMBLE SOLUTIONS AND THE
POSSIBILITY OF A DISSIPATION SCENARIO. 

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   TRACK 72-120 HR: MEDIUM
   INTENSITY 0 - 72 HR: HIGH
   INTENSITY 72-120 HR: LOW//
NNNN