meteo





TS DANAS(06W) still poorly organized with a fully exposed center


WARNING 4/JTWC


https://www.meteo974.re/M974World_r7.html
https://www.facebook.com/groups/1817419381676514/

WESTERN NORTH PACIFIC

TS DANAS(06W)
As of 00:00 UTC Jul 17, 2019:

Location: 18.1°N 123.5°E
Maximum Winds: 35 kt ( 65km/h)
Gusts: 45 kt (80km/h)

Minimum Central Pressure: 991 mb
WDPN31 PGTW 170300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 06W (DANAS)
WARNING NR 04//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 06W (DANAS), LOCATED APPROXIMATELY 255 NM NORTHEAST OF
MANILA, PHILIPPINES, HAS TRACKED NORTHWARD AT 08 KNOTS OVER THE PAST
SIX HOURS. THE CURRENT, HIGH-CONFIDENCE POSITION IS BASED ON A
170000Z PGTW SATELLITE FIX ON AN EXPOSED LOW-LEVEL CIRCULATION CENTER
(LLCC) EVIDENT IN VISIBLE SATELLITE IMAGERY. THE INTENSITY OF 35
KNOTS IS CONSISTENT WITH SUBJECTIVE DVORAK INTENSITY ESTIMATES FROM
MULTIPLE REPORTING AGENCIES, WHICH RANGE FROM 30 TO 35 KNOTS. TS 06W
TURNED SHARPLY POLEWARD ALONG THE PERIPHERY OF A REORIENTING STEERING
RIDGE TO THE EAST OVER THE PAST SIX HOUR. THE PRIMARY DEEP CONVECTION
ASSOCIATED WITH THE SYSTEM HAS BEEN DISPLACED TO THE WEST OF THE LLCC
BY PERSISTENT, MODERATE TO STRONG (20-25 KNOTS) EASTERLY VERTICAL
WIND SHEAR (VWS). WARM SEA SURFACE TEMPERATURES AND WESTWARD AND
EQUATORWARD DIFFLUENCE ALOFT REMAIN AS FAVORABLE OFFSETS TO THE VWS.
3. FORECAST REASONING.
   A. THE FORECAST TRACK HAS SHIFTED EASTWARD FROM THE PREVIOUS
WARNING AND MEDIUM RANGE INTENSITIES HAVE INCREASED SLIGHTLY DUE TO
LESS ANTICIPATED LAND INTERACTION. FORECAST WIND RADII HAVE ALSO
EXPANDED A BIT BASED ON LOWER ANTICIPATED LAND INFLUENCE ON THE
CIRCULATION. HOWEVER, THERE IS NO CHANGE TO THE OVERALL FORECAST
PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TS 06W WILL CONTINUE TRACKING GENERALLY POLEWARD THROUGHOUT THE
NEXT 72 HOURS AS IT FOLLOWS THE PERIPHERAL FLOW ASSOCIATED WITH A
REORIENTING SUBTROPICAL RIDGE TO THE EAST. SLOW INTENSIFICATION IS
LIKELY IN THE NEAR-TERM AS VERTICAL WIND SHEAR OFFSETS THE FAVORABLE
INFLUENCES OF PASSAGE OVER WARM WATER AND STRONG OUTFLOW ALOFT. THE
NUMERICAL MODEL GUIDANCE PACKAGE HAS SHIFTED SLIGHTLY EASTWARD FROM
THE PREVIOUS CYCLE, WITH THE ECMWF AND GFS SOLUTIONS BRACKETING THE
SET OF FORECASTS AS THE WESTERNMOST AND EASTERNMOST SOLUTIONS,
RESPECTIVELY.  THE CURRENT FORECAST FOLLOWS THE MOST PROBABLE
ORIENTATION OF THE LARGE-SCALE FLOW PATTERN, LIES SLIGHTLY TO THE
EAST OF THE PREVIOUS JTWC FORECAST AND LIES SLIGHTLY TO THE WEST OF
THE MULTI-MODEL CONSENSUS. THE LOW-LEVEL CIRCULATION PATTERN NEAR TS
06W REMAINS COMPLEX, WHICH IS INFLUENCING THE OUTCOME OF THE MODEL
FORECASTS. GIVEN NOTED SPREAD IN THE GUIDANCE, CONFIDENCE IN THE JTWC
TRACK FORECAST IS LOW.
  C. IN THE EXTENDED RANGE, TS 06W IS EXPECTED TO CONTINUE POLEWARD
AND EASTWARD AND UNDERGO A SLOW EXTRATROPICAL TRANSITION AS IT
ENCOUNTERS A DEVELOPING MID-LATITUDE TROUGH. SLIGHTLY WEAKENING IS
ANTICIPATED, ALTHOUGH FAVORABLE BAROCLINIC INTERACTION WITH THE
DEVELOPING TROUGH SHOULD ALLOW THE SYSTEM TO MAINTAIN GALE FORCE OR
STRONGER WINDS THROUGHOUT THE TRANSITION. THE STORM TRACK DURING THE
EXTENDED PERIOD IS HIGHLY DEPENDENT ON THE SOMEWHAT UNCERTAIN NEAR TO
MEDIUM-TERM TRACK, SO CONFIDENCE IN THE EXTENDED PORTION OF THE
FORECAST TRACK IS ALSO LOW.//
NNNN


TRACK AND INTENSITY GUIDANCE
TRACK AND INTENSITY GUIDANCE

TRACK GUIDANCE
TRACK GUIDANCE

INTENSITY GUIDANCE
INTENSITY GUIDANCE
Rédigé par PATRICK HOAREAU le Mercredi 17 Juillet 2019 à 10:55