2019 FEB 19 0840UTC WESTERN NORTH PACIFIC
TD #02W
TD #02W
WARNING 1/JTWC
As of 06:00 UTC Feb 19, 2019:
Location: 4.4°N 158.3°E
Maximum Winds: 25 kt (45km/h)
Gusts: 35 kt (65km/h)
Minimum Central Pressure: 1001 mb
Cheers,
Patrick Hoareau
WDPN31 PGTW 190900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (TWO)
WARNING NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 02W (TWO), LOCATED APPROXIMATELY 970 NM
SOUTHEAST OF ANDERSEN AFB, GUAM, HAS TRACKED WESTWARD AT 13 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS A CONSOLIDATING SYSTEM WITH IMPROVED DEEP CONVECTIVE BANDING
OVER THE NORTHERN AND WESTERN SEMICIRCLES OF A PARTIALLY-EXPOSED,
BROAD LOW-LEVEL CIRCULATION. A 190812Z SSMIS 91GHZ COLOR COMPOSITE
MICROWAVE IMAGE (MI) DEPICTS SHALLOW BANDING OVER THE EASTERN
SEMICIRCLE WRAPPING INTO A DEFINED LOW-LEVEL CIRCULATION CENTER
POSITIONED ON THE EASTERN EDGE OF AN AREA OF PERSISTENT CORE
CONVECTION AND FORMATIVE BANDING. BASED ON THE MI, THERE IS FAIR
CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS
ASSESSED AT 25 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T1.5 (25
KNOTS) FROM ALL AGENCIES. ENVIRONMENTAL CONDITIONS ARE VERY
FAVORABLE WITH LOW TO MODERATE VERTICAL WIND SHEAR, GOOD EQUATORWARD
OUTFLOW, STRONG POLEWARD OUTFLOW ENHANCED BY THE MIDLATITUDE
WESTERLIES, WARM SST (29 TO 30C) AND HIGH OCEAN HEAT CONTENT VALUES.
TD 02W IS CURRENTLY TRACKING WESTWARD ALONG THE SOUTHEASTERN
PERIPHERY OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED
TO THE NORTH AND NORTHWEST.
3. FORECAST REASONING.
A. THIS IS THE FIRST PROGNOSTIC REASONING MESSAGE AND SETS THE
FORECAST PHILOSOPHY.
B. THROUGH TAU 72, TD 02W IS EXPECTED TO TRACK WESTWARD TO WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED STR
ENTRENCHED TO THE NORTH. DUE TO THE FAVORABLE ENVIRONMENTAL
CONDITIONS, THE SYSTEM IS FORECAST TO INTENSIFY STEADILY, NEAR
CLIMATOLOGICAL RATE OF INTENSIFICATION, TO 70 KNOTS BY TAU 72.
NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A SPREAD OF 165NM
AT TAU 72.
C. IN THE EXTENDED PERIOD, UNCERTAINTY INCREASES SIGNIFICANTLY
WITH A BIFURCATION IN THE MODEL GUIDANCE. GFS (AND THE GFS ENSEMBLE)
AND NAVGEM INDICATE A RECURVE SCENARIO JUST WEST OF GUAM, WHICH
APPEARS UNLIKELY (LOW PROBABILITY). BOTH THESE MODELS ERRONEOUSLY
DRIVE THE SYSTEM DIRECTLY INTO AND THROUGH A STRONG STR POSITIONED
OVER GUAM WITH NO MIDLATITUDE SHORTWAVE TROUGH PRESENT...IN FACT,
GFS AND NAVGEM SHOW A BROAD STR TO THE EAST OF JAPAN. THE REMAINDER
OF THE DYNAMIC MODEL GUIDANCE (ECMF, EEMN, HWRF, JGSM, EGRR)
INDICATES A FLATTER TRACK MUCH FURTHER TO THE SOUTHWEST WITH A WEST-
NORTHWESTWARD TO NORTHWESTWARD TRAJECTORY. THE JTWC OFFICIAL
FORECAST FAVORS A NON-RECURVE SCENARIO CLOSER TO THE ECMWF SOLUTION
DUE TO THE LACK OF A MIDLATITUDE RECURVE MECHANISM (DEEP SHORTWAVE
TROUGH AND ASSOCIATED FRONTAL SYSTEM), AND PRESENCE OF A STRONG STR.
TD 02W IS FORECAST, HOWEVER, TO INTENSIFY TO 90 KNOTS AS IT SKIRTS
SOUTH OF GUAM, AND MAY STILL PRODUCE GALE-FORCE SUSTAINED WINDS AND
ISOLATED GUSTS NEAR 50 KNOTS OVER GUAM. OVERALL, CONFIDENCE REMAINS
LOW DUE TO THE BIFURCATION IN THE NUMERICAL GUIDANCE.//
NNNN
As of 06:00 UTC Feb 19, 2019:
Location: 4.4°N 158.3°E
Maximum Winds: 25 kt (45km/h)
Gusts: 35 kt (65km/h)
Minimum Central Pressure: 1001 mb
Cheers,
Patrick Hoareau
WDPN31 PGTW 190900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (TWO)
WARNING NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 02W (TWO), LOCATED APPROXIMATELY 970 NM
SOUTHEAST OF ANDERSEN AFB, GUAM, HAS TRACKED WESTWARD AT 13 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS A CONSOLIDATING SYSTEM WITH IMPROVED DEEP CONVECTIVE BANDING
OVER THE NORTHERN AND WESTERN SEMICIRCLES OF A PARTIALLY-EXPOSED,
BROAD LOW-LEVEL CIRCULATION. A 190812Z SSMIS 91GHZ COLOR COMPOSITE
MICROWAVE IMAGE (MI) DEPICTS SHALLOW BANDING OVER THE EASTERN
SEMICIRCLE WRAPPING INTO A DEFINED LOW-LEVEL CIRCULATION CENTER
POSITIONED ON THE EASTERN EDGE OF AN AREA OF PERSISTENT CORE
CONVECTION AND FORMATIVE BANDING. BASED ON THE MI, THERE IS FAIR
CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS
ASSESSED AT 25 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T1.5 (25
KNOTS) FROM ALL AGENCIES. ENVIRONMENTAL CONDITIONS ARE VERY
FAVORABLE WITH LOW TO MODERATE VERTICAL WIND SHEAR, GOOD EQUATORWARD
OUTFLOW, STRONG POLEWARD OUTFLOW ENHANCED BY THE MIDLATITUDE
WESTERLIES, WARM SST (29 TO 30C) AND HIGH OCEAN HEAT CONTENT VALUES.
TD 02W IS CURRENTLY TRACKING WESTWARD ALONG THE SOUTHEASTERN
PERIPHERY OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED
TO THE NORTH AND NORTHWEST.
3. FORECAST REASONING.
A. THIS IS THE FIRST PROGNOSTIC REASONING MESSAGE AND SETS THE
FORECAST PHILOSOPHY.
B. THROUGH TAU 72, TD 02W IS EXPECTED TO TRACK WESTWARD TO WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED STR
ENTRENCHED TO THE NORTH. DUE TO THE FAVORABLE ENVIRONMENTAL
CONDITIONS, THE SYSTEM IS FORECAST TO INTENSIFY STEADILY, NEAR
CLIMATOLOGICAL RATE OF INTENSIFICATION, TO 70 KNOTS BY TAU 72.
NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A SPREAD OF 165NM
AT TAU 72.
C. IN THE EXTENDED PERIOD, UNCERTAINTY INCREASES SIGNIFICANTLY
WITH A BIFURCATION IN THE MODEL GUIDANCE. GFS (AND THE GFS ENSEMBLE)
AND NAVGEM INDICATE A RECURVE SCENARIO JUST WEST OF GUAM, WHICH
APPEARS UNLIKELY (LOW PROBABILITY). BOTH THESE MODELS ERRONEOUSLY
DRIVE THE SYSTEM DIRECTLY INTO AND THROUGH A STRONG STR POSITIONED
OVER GUAM WITH NO MIDLATITUDE SHORTWAVE TROUGH PRESENT...IN FACT,
GFS AND NAVGEM SHOW A BROAD STR TO THE EAST OF JAPAN. THE REMAINDER
OF THE DYNAMIC MODEL GUIDANCE (ECMF, EEMN, HWRF, JGSM, EGRR)
INDICATES A FLATTER TRACK MUCH FURTHER TO THE SOUTHWEST WITH A WEST-
NORTHWESTWARD TO NORTHWESTWARD TRAJECTORY. THE JTWC OFFICIAL
FORECAST FAVORS A NON-RECURVE SCENARIO CLOSER TO THE ECMWF SOLUTION
DUE TO THE LACK OF A MIDLATITUDE RECURVE MECHANISM (DEEP SHORTWAVE
TROUGH AND ASSOCIATED FRONTAL SYSTEM), AND PRESENCE OF A STRONG STR.
TD 02W IS FORECAST, HOWEVER, TO INTENSIFY TO 90 KNOTS AS IT SKIRTS
SOUTH OF GUAM, AND MAY STILL PRODUCE GALE-FORCE SUSTAINED WINDS AND
ISOLATED GUSTS NEAR 50 KNOTS OVER GUAM. OVERALL, CONFIDENCE REMAINS
LOW DUE TO THE BIFURCATION IN THE NUMERICAL GUIDANCE.//
NNNN
2019 FEB 19 0827UTC
