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Tropical Storm KAMMURI Advisory Wed Nov 27

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 29W (KAMMURI)
WARNING NR 007//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM (TS) 29W (KAMMURI), LOCATED APPROXIMATELY 204 NM
NORTHEAST OF YAP, HAS TRACKED WESTWARD AT 14 KNOTS OVER THE PAST SIX
HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS AN
EXPANSIVE SYSTEM WITH CENTRAL DENSE OVERCAST OBSCURING THE LOW LEVEL
CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS POSITIONED WITH
FAIR CONFIDENCE BASED ON BANDING SEEN IN MSI. THE INITIAL INTENSITY
OF 55 KNOTS IS BASED ON THE DVORAK ESTIMATE OF T3.5 (55 KNOTS) FROM
PGTW AND IS FURTHER SUPPORTED BY A 270336Z SATCON ESTIMATE OF 57
KNOTS. ENVIRONMENTAL ANALYSES REVEAL A FAVORABLE ENVIRONMENT WITH
STRONG POLEWARD OUTFLOW, LOW TO MODERATE (15-20 KNOT) VERTICAL WIND
SHEAR, AND VERY WARM (30 DEGREES CELSIUS) SEA SURFACE TEMPERATURES.
THE CYCLONE IS TRACKING IN THE PHILIPPINE SEA ALONG THE SOUTHERN
PERIPHERY OF THE SUBTROPICAL RIDGE (STR) POSITIONED TO THE
NORTHEAST.
3. FORECAST REASONING.
   A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM
THE LAST PROGNOSTIC REASONING MESSAGE.
   B. TS 29W WILL GRADUALLY TRANSITION TO A NORTHERLY TRACK BY TAU
24 AS A SHORTWAVE TROUGH APPROACHES FROM THE NORTHWEST, WEAKENING
THE AFOREMENTIONED STR AND ALLOWING A COL TO FORM. AROUND TAU 48,
THE ORIGINAL STEERING STR WILL RE-BUILD AND RE-DIRECT TS 29W
WESTWARD. THE OVERALL FAVORABLE ENVIRONMENT WILL LIKELY FUEL STEADY
TO RAPID INTENSIFICATION OF TS 29W TO 105 KNOTS BY TAU 72. THERE IS
SOME UNCERTAINTY IN THE INTENSITY GUIDANCE DUE TO SHEAR AND POSSIBLE
CONVERGENCE ALOFT. HOWEVER, WITH THE EXCEPTION OF NAVGEM WITH A MORE
NORTHWESTERLY TRACK, THERE IS OVERALL GOOD CONFIDENCE IN THIS
PORTION OF THE FORECAST.
   C. AFTER TAU 72, TS 29W WILL CONTINUE ITS TRACK WESTWARD UNDER
THE STR. THE FAVORABLE CONDITIONS ARE EXPECTED TO SUSTAIN FURTHER
INTENSIFICATION TO 115 KNOTS UP TO TAU 120. UNCERTAINTY REMAINS IN
THE EFFECTS OF SUSTAINED MODERATE SHEAR AND POSSIBLE CONVERGENCE
ALOFT, LENDING FAIR CONFIDENCE IN THE INTENSITY GUIDANCE. NUMERICAL
MODELS ARE IN OVERALL GOOD AGREEMENT WITH THE OVERALL FORECAST
TRACK, WITH THE EXCEPTION OF AN EARLY RECURVE BY JGSM AND NAVGEM.
HOWEVER, THE DIFFERENCES IN ALONG-TRACK SPEED IN LATER TAUS AND THE
STORM MOTION UNCERTAINTY IN THE COL, GIVE FAIR CONFIDENCE TO THE
JTWC TRACK FORECAST.//
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