JMA 15Z:
WTPQ20 RJTD 141500
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 1013 MEGI (1013)
ANALYSIS
PSTN 141500UTC 13.2N 138.2E FAIR
MOVE NW 08KT
PRES 990HPA
MXWD 045KT
GUST 065KT
30KT 140NM NORTHEAST 100NM SOUTHWEST
FORECAST
24HF 151500UTC 15.0N 134.7E 70NM 70%
MOVE WNW 10KT
PRES 975HPA
MXWD 060KT
GUST 085KT
45HF 161200UTC 16.5N 131.1E 140NM 70%
MOVE WNW 11KT
PRES 960HPA
MXWD 075KT
GUST 105KT
69HF 171200UTC 17.4N 127.2E 160NM 70%
MOVE W 10KT
PRES 950HPA
MXWD 080KT
GUST 115KT =
From JMA 12Z:
96HF 181200UTC 17.7N 123.3E 200NM 70%
MOVE W 09KT
120HF 191200UTC 17.8N 119.6E 260NM 70%
MOVE W 09KT =
JTWC 15Z:
WTPN31 PGTW 141500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 15W (MEGI) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
141200Z --- NEAR 13.1N 138.5E
MOVEMENT PAST SIX HOURS - 300 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.1N 138.5E
---
FORECASTS:
12 HRS, VALID AT:
150000Z --- 14.0N 137.0E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 300 DEG/ 10 KTS
---
24 HRS, VALID AT:
151200Z --- 15.0N 135.2E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 295 DEG/ 12 KTS
---
36 HRS, VALID AT:
160000Z --- 16.0N 132.9E
MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 290 DEG/ 12 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
161200Z --- 16.8N 130.6E
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 280 DEG/ 11 KTS
---
72 HRS, VALID AT:
171200Z --- 17.4N 126.2E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
125 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 270 DEG/ 11 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
181200Z --- 17.2N 121.8E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 265 DEG/ 10 KTS
---
120 HRS, VALID AT:
191200Z --- 16.7N 117.6E
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
141500Z POSITION NEAR 13.3N 138.1E.
TROPICAL STORM (TS) 15W (MEGI) LOCATED APPROXIMATELY 210 NM
NORTH OF YAP, HAS TRACKED WEST-NORTHWESTWARD AT 08 KNOTS OVER
THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 141200Z
IS 13 FEET. NEXT WARNINGS AT 142100Z, 150300Z, 150900Z AND
151500Z.//
NNNN
WDPN31 PGTW 141500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (MEGI) WARNING
NR 07//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
A. TROPICAL STORM (TS) 15W (MEGI) LOCATED APPROXIMATELY 210 NM
NORTH OF YAP, HAS TRACKED WEST-NORTHWESTWARD AT 08 KNOTS OVER THE
PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY DEPICTS
SLIGHTLY IMPROVED CONSOLIDATION WITH A CENTRAL DENSE OVERCAST
FEATURE EVIDENT. A 140903Z SSMIS IMAGE INDICATES IMPROVED
CONVECTIVE BANDING OVER THE WESTERN SEMI-CIRCLE ALTHOUGH THE
BULK OF THE DEEP CONVECTION REMAINS OVER THE EASTERN SEMI-CIRCLE.
THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION BASED ON THE WELL-
DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC) EVIDENT IN THE 140903Z
IMAGE AS WELL AS IN A 141110Z SSMIS 37H IMAGE. THE CURRENT
INTENSITY IS ASSESSED AT 60 KNOTS BASED ON AN AVERAGE OF DVORAK
ESTIMATES RANGING FROM 55 TO 65 KNOTS FROM KNES AND PGTW AS WELL
AS EARLIER (140436Z) AIRCRAFT RECONNAISSANCE DATA INDICATING 62
KNOT MAXIMUM SUSTAINED WINDS; RJTD IS CURRENTLY AT 50 KNOTS (T3.0).
OVERALL, UPPER-LEVEL OUTFLOW IS GOOD WITH THE EXCEPTION OF SOME
PRESSURE ON THE WEST SIDE RESULTING FROM THE CLOSE PROXIMITY OF
AN ANTICYCLONE NEAR 10N 130E, ASSOCIATED WITH A WEAK TROPICAL
DISTURBANCE. THIS DISTURBANCE MAY ALSO BE DISRUPTING LOW-LEVEL
INFLOW OVER THE SOUTHWEST QUADRANT.
3. FORECAST REASONING.
A. NO CHANGE SINCE THE 140300Z BULLETIN.
B. TS 15W IS CURRENTLY TRACKING ALONG THE SOUTHWEST PERIPHERY OF
THE MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTHEAST
TOWARD A WEAKNESS PRODUCED BY A MAJOR MIDLATITUDE SHORT-WAVE TROUGH
SITUATED OVER NORTHEAST ASIA. THIS TROUGH IS EXPECTED TO FILL AND
PROPAGATE NORTHEASTWARD, WHICH WILL ALLOW THE STR TO BUILD NORTH OF
THE SYSTEM PROVIDING A WESTWARD STEERING INFLUENCE. AVAILABLE MODEL
GUIDANCE IS TIGHTLY-CLUSTERED THEREFORE THE FORECAST IS IN CLOSE
AGREEMENT WITH THE MODEL CONSENSUS. TS 15W IS FORECAST TO INTENSIFY
AT A 15-25 KNOT PER DAY RATE THROUGH TAU 48 WITH RAPID
INTENSIFICATION LIKELY AFTER TAU 24 DUE TO IMPROVING OUTFLOW.
C. AFTER TAU 72, TS 15W IS FORECAST TO CONTINUE TRACKING WESTWARD
AND SHOULD MAKE LANDFALL OVER LUZON BY TAU 96. MODEL GUIDANCE IS
TIGHTLY-CLUSTERED THROUGH TAU 120. TS 15W IS EXPECTED TO PEAK AT
120 KNOTS BY TAU 96 AND SHOULD WEAKEN CONSIDERABLY AFTER CROSSING
THE MOUNTAINOUS REGION OF LUZON AND RE-EMERGE INTO THE SOUTH CHINA
SEA AT 80-90 KNOTS.//
NNNN
KNES Dvorak up to T4.0:
TXPN23 KNES 141525
SIMWIR
A. 15W (MEGI)
B. 14/1430Z
C. 13.3N
D. 138.0E
E. THREE/MTSAT
F. T4.0/4.0/D1.5/24HRS
G. IR/EIR/SSMIS
H. REMARKS...SYSTEM ORGANIZATION IMPROVED WITH DT=4.0 BASED ON 10/10
WHITE
BANDING. MET=3.5 BUT PAT=4.0. FT BASED ON PT.
I. ADDL POSITIONS
14/0903Z 13.1N 138.8E SSMIS
...SWANSON
=
