Tropical Storm NALGAE Advisory Do, 27.10.

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 26W (TWENTYSIX)
WARNING NR 001//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
   INITIAL POSITION: 12.6N 130.7E
   INITIAL INTENSITY: 25 KTS
   GEOGRAPHIC REFERENCE: 386 NM NORTHWEST OF KOROR, PALAU
   MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 08 KTS
   SIGNIFICANT WAVE HEIGHT: 10 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A SYSTEM IN
THE PHILIPPINE SEA THAT IS DISORGANIZED BUT SLOWLY CONSOLIDATING
WITH FLARING CENTRAL CONVECTION AND FORMATIVE AND FRAGMENTED RAIN
BANDS EXTENDING OUT TO APPROXIMATELY 230 NM NE-SW. THE NORTHWEST
PERIPHERIES EXPOSE A SMALL PORTION OF THE LOW LEVEL CIRCULATION
(LLC) AND ALSO SHOWS A STEADY STREAM OF STRATOCUMULUS LINES
ASSOCIATED WITH THE COLD NORTHEAST SURGE. RECENT SCATTEROMETRY DATA
INDICATES THE LOW-LEVEL CIRCULATION IS WEAK AND ELONGATED WITH THE
STRONGER WINDS MORE THAN 60NM TO THE EAST. THE INITIAL POSITION IS
PLACED WITH MEDIUM CONFIDENCE BASED ON A LARGE AND RAGGED BUT DEFINED
LLC FEATURE IN THE 2213Z SSMIS MICROWAVE IMAGE. THE INITIAL INTENSITY
IS EXTRAPOLATED FROM RECENT SCATTEROMETRY DATA AND REFLECTS THE
SUSTAINED 6-HR WEAK SIGNATURE IN THE ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY.
INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).
CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO
THE NORTHEAST.
AGENCY DVORAK AND AUTOMATED FIXES:
   PGTW: T2.0 - 30 KTS
   RJTD: T2.0 - 30 KTS
   KNES: T1.5 - 25 KTS
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 0-5 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: STRONG POLEWARD
ANALYSIS CONFIDENCE:
   INITIAL POSITION: LOW
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: NOT APPLICABLE
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING
MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY.
FORECAST DISCUSSION: TD 26W IS EXPECTED TO TRACK MORE NORTHWESTWARD
ALONG THE SOUTHWEST PERIPHERY OF THE STR, MAKING LANDFALL NEAR
AURORA PROVINCE, PHILIPPINES, AROUND TAU 60, THEN EXIT INTO THE
SOUTH CHINA SEA AROUND TAU 84. AFTERWARD, THE CYCLONE WILL TRACK
MORE NORTHWARD AS THE STR IS WEAKENED BY A MID-LATITUDE TROUGH TO
THE NORTH. THE FAVORABLE CONDITIONS WILL FUEL A STEADY
INTENSIFICATION TO A PEAK OF 75KTS BY TAU 48, POSSIBLY HIGHER. AFTER
LANDFALL, INTERACTION WITH THE RUGGED LUZON TERRAIN WILL REDUCE IT TO
55KTS, THE RE-INTENSIFY TO 60KTS AFTER IT EXITS INTO THE WARM WATERS
OF THE SOUTH CHINA SEA AND INTO LUZON STRAIT.
MODEL DISCUSSION: NUMERICAL MODELS WIDELY AND UNEVENLY SPREAD OUT
TO 390 NM BY TAU 120 WITH NVGM ON THE LEFT- AND AEMN ON THE
RIGHT-MARGIN OF THE ENVELOPE. THIS, PLUS THE FORMATIVE NATURE OF
THE SYSTEM, LENDS OVERALL LOW CONFIDENCE IN THE JTWC TRACK FORECAST.
FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: LOW
   TRACK 72-120 HR: LOW
   INTENSITY 0 - 72 HR: LOW
   INTENSITY 72-120 HR: LOW//
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