Tropical Storm MAN-YI Advisory 11月22日

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 34W (MAN-YI) WARNING NR 09//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON 34W (MAN-YI), LOCATED APPROXIMATELY 253 NM SOUTH-SOUTHWEST
OF ANDERSEN AFB, GUAM, HAS TRACKED WEST-NORTHWESTWARD AT 27 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY SHOWS A FAST-MOVING, EXPANSIVE, AND RAPIDLY INTENSIFYING
SYSTEM THAT HAS FORMED A PINHOLE 3-NM EYE. THE INITIAL POSITION IS
PLACED JUST BEHIND THE EIR PINHOLE EYE AND ON TOP OF THE DEFINED
MICROWAVE EYE FEATURE IN THE 211756Z GPM 36GHZ IMAGE WITH HIGH
CONFIDENCE. THE INITIAL INTENSITY OF 65 KNOTS IS CONSISTENT WITH THE
PGUA AND KNES DVORAK ESTIMATES OF T4.0/65KTS. THE ENVIRONMENT IS
EXCEPTIONALLY FAVORABLE WITH LOW (10-15 KNOT) RELATIVE VERTICAL WIND
SHEAR (VWS), RADIAL OUTFLOW, AND WARM (29-30 CELSIUS) SEA SURFACE
TEMPERATURE. TY 34W IS TRACKING QUICKLY ALONG THE SOUTHWESTERN
PERIPHERY OF A SUBTROPICAL RIDGE (STR).
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. THROUGH TAU 36, THE STR WILL CONTINUE STEERING TY 34W WEST-
NORTHWESTWARD. AFTERWARD, AN APPROACHING MID-LATITUDE TROUGH WILL
CREATE A WEAKNESS IN THE STR AND SHIFT THE TRACK NORTHWARD. THE
ENVIRONMENT WILL REMAIN FAVORABLE FOR INTENSIFICATION IN THE NEAR
TERM, PEAKING AT 95 KNOTS AROUND TAU 24 BEFORE GRADUALLY WEAKENING TO
75 KNOTS BY TAU 48 AS VWS INCREASES. AFTER TAU 48, TY 34W WILL
SLIGHTLY RE-INTENSIFY AS POLEWARD OUTFLOW INCREASES DUE TO INITIAL
EXPOSURE TO THE PREVAILING WESTERLIES, REACHING 75 KNOTS BY TAU 72.
MODEL GUIDANCE IS IN EXCELLENT AGREEMENT THROUGH TAU 48 BUT SPREAD
BEGINS TO INCREASE AFTERWARD. OVERALL, THERE IS MODERATE CONFIDENCE
IN THIS PORTION OF THE JTWC TRACK FORECAST.
   C. BEYOND TAU 72, TY MAN-YI WILL TURN NORTHWESTWARD AS THE STR
BUILDS BACK TO THE NORTH. THE ROBUST WESTERLY OUTFLOW WILL SUSTAIN
CONTINUED INTENSIFICATION UP TO 80 KNOTS AT TAU 96; AFTERWARD,
MODERATE VWS, UPPER LEVEL CONVERGENCE, AND DRY AIR ENTRAINMENT ARE
EXPECTED TO CAUSE SIGNIFICANT WEAKENING, BRINGING THE INTENSITY DOWN
TO 45 KNOTS BY TAU 120. THERE IS A SIGNIFICANT SPREAD IN THE
NUMERICAL MODEL GUIDANCE, REACHING A SPAN OF OVER 600 NM WITH JGSM ON
THE EXTREME LEFT AND NVGM ON THE EXTREME RIGHT OF THE MODEL ENVELOPE.
THE JTWC TRACK FORECAST LIES NEAR THE CONSENSUS TRACK WITH LOW
CONFIDENCE.//
NNNN
NNNN