Tropical Storm Kalmaegi & Typhoon Fengshen: updates at 16/03UTC

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WESTERN NORTH PACIFIC

TY FENGSHEN (26W)
As of 00:00 UTC Nov 16, 2019:
Location: 23.8°N 143.2°E
Maximum Winds: 110 kt ( 205km/h)
Gusts: 135 kt ( 250km/h)
Minimum Central Pressure: 953 mb
CATEGORY US: 3
WDPN31 PGTW 160300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 26W (FENGSHEN) WARNING NR 019//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 26W (FENGSHEN), LOCATED APPROXIMATELY 120 NM EAST-
SOUTHEAST OF IWO TO, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 15
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS THE SYSTEM HAS MAINTAINED OVERALL CONVECTIVE
STRUCTURE AND A 10NM PINHOLE EYE SURROUNDED BY DEEP COMPACT CENTRAL
CONVECTION. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE
BASED ON THE EYE FEATURE AND LINED UP WITH A MICROWAVE EYE IN THE
152135Z SSMIS 37GHZ COLORIZED IMAGE. THE INITIAL INTENSITY OF 110KTS
IS AVERAGED FROM AGENCY DVORAK ESTIMATES OF T5.5/102KTS TO
T6.0/115KTS AND REFLECTS THE SUSTAINED CONVECTIVE STRUCTURE. TY 26W
IS IN AN AREA OF LOW TO MODERATE (10-15KT) VERTICAL WIND SHEAR
(VWS), OFFSET BY WARM (28-29C) SSTS AND EXCELLENT POLEWARD OUTFLOW.
THE CYCLONE HAS CRESTED THE WESTERN EDGE OF A DEEP-LAYERED
SUBTROPICAL RIDGE (STR) TO THE EAST AND IS NOW ON THE POLEWARD SIDE.
3. FORECAST REASONING.
   A.  THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY
FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TY 26W IS FORECAST TO TRACK NORTHEASTWARD THEN EASTWARD UNDER
THE STR. AFTER TAU 36, AS THE SYSTEM ERODES DUE TO INCREASING VWS
AND COOLING SSTS, A SECONDARY, MID- TO LOW-LAYERED STR TO THE NORTH
WILL ASSUME STEERING AND LOOP THE CYCLONE WESTWARD. THE NEGATIVE
COMBINED EFFECTS OF HIGH VWS AND COOL SSTS WILL RESULT IN
DISSIPATION BY TAU 72. THE MAJORITY OF THE NUMERICAL MODELS ARE IN
BROAD AGREEMENT WITH THIS LOOPING TRACK BUT WITH SIGNIFICANT
DIFFERENCES IN THE TRACK SPEED AND THE TIMING OF THE TURNS. IN VIEW
OF THIS COMPLEX STEERING AND THE LARGE VARIANCE IN THE NUMERICAL
MODEL SOLUTIONS, THERE IS LOW CONFIDENCE IN THE JTWC TRACK
FORECAST.//
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TS KALMAEGI (27W)
As of 00:00 UTC Nov 16, 2019:
Location: 16.1°N 125.8°E
Maximum Winds: 35 kt ( 65km/h)
Gusts: 45 kt ( 85km/h)
Minimum Central Pressure: 1000 mb
WDPN32 PGTW 160300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 27W (KALMAEGI)
WARNING NR 014//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM (TS) 27W (KALMAEGI), LOCATED APPROXIMATELY 292
NM EAST-NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT
02 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS A LARGE AREA OF DEEP CONVECTION LOOSELY WRAPPING
INTO A BROAD, ELONGATED, RAGGED, AND OBSCURED LOW LEVEL CIRCULATION
(LLC). THE INITIAL POSITION IS PLACED WITH LOW CONFIDENCE BY TRACING
THE LOW CLOUD ELEMENTS IN THE MSI LOOP INTO THE LLC. THE INITIAL
INTENSITY OF 35KTS IS BASED ON THE DVORAK ESTIMATE OF T2.5/35KTS
FROM RJTD AND IS SUPPORTED BY OBJECTIVE DVORAK ESTIMATES. ANALYSES
INDICATE A MARGINAL ENVIRONMENT WITH A VIGOROUS POLEWARD OUTFLOW AND
WARM (29C) SSTS OFFSET BY MODERATE TO STRONG (15-25KT) RELATIVE
VERTICAL WIND SHEAR (VWS) AND COOL/DRY NORTHEASTERLY SURGE OVER THE
PHILIPPINE SEA. THE CYCLONE IS QUASI-STATIONARY (QS) IN A WEAK
STEERING ENVIRONMENT IN A COL BETWEEN THE SUBTROPICAL RIDGE (STR) TO
THE WEST AND THE STR TO THE EAST.
3. FORECAST REASONING.
   A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM
THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TS 27W WILL REMAIN QS OVER THE NEXT 24HRS. AFTERWARD, THE STR
TO THE EAST WILL SLOWLY DRIVE THE SYSTEM NORTHWESTWARD. BETWEEN TAUS
48 AND 72, THE STR TO THE WEST WILL BUILD, REORIENT NORTHWARD, AND
GRADUALLY STEER THE CYCLONE WESTWARD INTO NORTHERN LUZON. THE
MARGINALLY FAVORABLE ENVIRONMENT WILL FUEL SLOW INTENSIFICATION TO A
PEAK OF 55KTS BY TAU 48. AFTERWARD, INCREASING VWS AND LAND
INTERACTION WILL ERODE THE SYSTEM DOWN TO 40KTS AFTER LANDFALL.
THERE IS A DISTINCT POSSIBILITY THAT THE STRONG VWS, COLD/DRY SURGE,
AND LAND INTERACTION WILL GREATLY OFFSET THE STRONG OUTFLOW AND
ERODE THE SYSTEM MORE RAPIDLY AND INTO DISSIPATION BY TAU 72.
   C. AFTER TAU 72, TS KALMAEGI IS EXPECTED TO TRACK SOUTHWESTWARD
UNDER THE SECONDARY STR, NOW POSITIONED TO THE NORTHWEST, AND AROUND
TAU 82, EXIT INTO THE SOUTH CHINA SEA WHERE THE COLD/DRY NORTHERLY
SURGE IS MORE VIGOROUS. THIS, PLUS THE HIGH VWS, WILL RESULT IN
DISSIPATION BY TAU 120. THE NUMERICAL MODELS ARE IN VERY BROAD
AGREEMENT TO THE FORECAST TRACK BUT WITH SIGNIFICANT DIFFERENCES IN
TRACK SPEED GIVEN THE UNCERTAINTIES IN THE STORM MOTION IN THE COL
AND ACROSS THE RUGGED LUZON TERRAIN. IN VIEW OF THESE, THERE IS LOW
CONFIDENCE IN THE JTWC TRACK FORECAST.//
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