WPAC: NESAT - Post-Tropical

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WDPN34 PGTW 282100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 11W (NESAT) WARNING NR
12//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON (TY) 11W (NESAT), LOCATED APPROXIMATELY 237 NM SOUTH-
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 08
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS IMPROVED CORE CONVECTION, WHICH HAS BECOME MORE
CONSOLIDATED AND MORE SYMMETRIC OVER THE PAST SIX HOURS. DUE TO THE
LACK OF MICROWAVE IMAGERY AND CENTRAL CONVECTION OBSCURTING THE
CENTER, THERE IS FAIR CONFIDENCE IN THE INITIAL POSITION. THE
INITIAL INTENSITY IS ASSESSED AT 75 KNOTS BASED ON DVORAK INTENSITY
ESTIMATES RANGING FROM T4.5 (77 KNOTS) FROM PGTW. UPPER-LEVEL
ANALYSIS INDICATES IMPROVING POLEWARD OUTFLOW. TY 11W IS TRACKING
ALONG THE SUBTROPICAL RIDGE (STR) ANCHORED OVER THE EAST CHINA
SEA.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 11W IS FORECAST TO TRACK NORTHWESTWARD UNDER THE STEERING
INFLUENCE OF THE STR ENTRENCHED TO THE NORTH. THE SYSTEM SHOULD MAKE
LANDFALL JUST AFTER TAU 12 AND WILL WEAKEN RAPIDLY AS IT TRACKS
ACROSS TAIWAN. AFTER RE-EMERGING OVER THE TAIWAN STRAIT, TY 11W WILL
MAKE ITS SECOND LANDFALL OVER EASTERN CHINA AFTER TAU 36 AND WILL
TURN POLEWARD AS THE STR RE-ORIENTS WITH THE APPROACH OF A
MIDLATITUDE TROUGH. THE SYSTEM IS EXPECTED TO DISSIPATE BETWEEN TAU
72 AND TAU 96. OVERALL, GLOBAL MODEL GUIDANCE IS IN GOOD AGREEMENT,
THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.//
NNNN

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TXPQ29 KNES 282111
TCSWNP

A. 11W (NESAT)

B. 28/2030Z

C. 21.6N

D. 123.5E

E. THREE/HIMAWARI-8

F. T5.0/5.0/D1.0/06HRS

G. IR/EIR/SWIR

H. REMARKS...CENTER IS EMBEDDED WITHIN CMG. THIS CONFERS A DT OF 5.0. MET
AND PT ARE BOTH 5.0. FT IS BASED OFF THE DT.

I. ADDL POSITIONS

NIL


...GAETANO

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Closing in.

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Looks like it completed a EWC and now a larger eye appeared.

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WDPN34 PGTW 290900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 11W (NESAT) WARNING NR
014//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 11W (NESAT), LOCATED APPROXIMATELY 126 NM SOUTH-SOUTHEAST
OF TAIPEI, TAIWAN, HAS TRACKED NORTH-NORTHWESTWARD AT 09 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS SYMMETRIC SPIRAL BANDING WITH ASSOCIATED DEEP CONVECTION.
THERE IS HIGH CONFIDENCE IN THE INITIAL POSITION WHICH IS BASED ON
RECENT SATELLITE FIXES AND ANIMATED RADAR IMAGERY FROM TAIWAN
SHOWING HEAVY TO MODERATE RAIN BANDS WRAPPING INTO THE CENTER. THE
INITIAL INTENSITY ASSESSMENT OF 80 KNOTS IS BASED ON MULTI-AGENCY
DVORAK ESTIMATES RANGING FROM T4.5 TO T5.0 (77 TO 90 KNOTS). UPPER-
LEVEL ANALYSIS SHOWS RADIAL OUTFLOW OVER THE SYSTEM WITH SOME
HINDRANCE FROM NEARBY TS HAITANG TO THE SOUTHWEST AND AN UPPER-LEVEL
RIDGE TO THE NORTH. VERTICAL WIND SHEAR HAS REMAINED FAVORABLE AND
SSTS ARE CURRENTLY AROUND 30 CELSIUS, VERY CONDUCIVE FOR
INTENSIFICATION. TY 11W IS TRACKING NORTH-NORTHWESTWARD ALONG A
BUILDING SUBTROPICAL RIDGE ANCHORED OVER THE EAST CHINA
SEA.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 11W IS FORECAST TO CONTINUE TRACKING NORTHWESTWARD GUIDED
BY THE NORTHERN STEERING RIDGE. LANDFALL OVER TAIWAN IS EXPECTED IN
THE NEXT SIX HOURS, AT WHICH TIME INTENSITY IS EXPECTED TO DECREASE
SIGNIFICANTLY. TY NESAT IS EXPECTED TO REEMERGE OVER THE TAIWAN
STRAIT SOMETIME BETWEEN TAU 12 AND 18 AND REORGANIZE AS A TROPICAL
STORM MAINTAINING AN INTENSITY OF 55 KNOTS. BETWEEN TAU 24 AND 36 TY
NESAT WILL MAKE LANDFALL AGAIN OVER CHINA. DURING THIS TIME THE
STEERING RIDGE WILL REORIENT ON A NORTH-SOUTH AXIS CAUSING TY NESAT
TO ABRUPTLY TURN NORTH AND ACCELERATE. TS HAITANG WILL ALSO INTERACT
WITH TY NESAT AROUND THIS TIME. TS HAITANG WILL APPROACH FROM THE
SOUTHEAST AND THE TWO SYSTEMS WILL MERGE WHILE OVER CHINA AROUND TAU
48. DYNAMIC MODEL GUIDANCE SHOWS FAIRLY GOOD AGREEMENT, BUT THERE IS
A DEGREE OF UNCERTAINTY IN WHERE THE SYSTEM WILL EMERGE IN THE
TAIWAN STRAIT. OVERALL THERE IS HIGH CONFIDENCE IN THE FORECAST
TRACK.
NNNN

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Made landfall near Su'ao.

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Yonaguni got wind gust of up to 112 mph.

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So far the peak gust in Taipei, 2.7 million, is just 47 knots but the track should take it very close to the city in the coming hours.

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Double landfall...

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WDPN34 PGTW 292100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 11W (NESAT) WARNING NR
016//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 11W (NESAT), LOCATED APPROXIMATELY 65 NM WEST
OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 14 KNOTS OVER
THE PAST SIX HOURS. TS 11W HAS RE-EMERGED OVER THE TAIWAN STRAIT
AFTER CROSSING NORTHERN TAIWAN. SURFACE OBSERVATIONS AT SU-AO BUOY
(24.61N 121.88E), JUST PRIOR TO LANDFALL ALONG THE NORTHEAST COAST
OF TAIWAN, INDICATED MAXIMUM 10-MIN SOUTHERLY WINDS OF 56 GUSTING TO
76 KNOTS AND A MINIMUM SLP OF 964.8MB. SURFACE OBSERVATIONS ALONG
THE NORTHWEST COAST OF TAIWAN AT HSINCHU BUOY (24.76N 120.84E) AT
29/17Z INDICATED MAXIMUM 10-MIN WINDS OF 42 GUSTING TO 54 KNOTS.
THIS WEAKENING TREND IS CLEARLY INDICATED IN ANIMATED ENHANCED
INFRARED SATELLITE IMAGERY, WHICH SHOWS RAPIDLY DECAYING CONVECTIVE
STRUCTURE WITH WARMING CLOUD TOPS, AND ANIMATED RADAR IMAGERY FROM
TAIWAN. THE CURRENT POSITION IS BASED ON THE RADAR IMAGERY WITH
EXCELLENT CONFIDENCE. THE CURRENT INTENSITY IS ASSESSED AT 60 KNOTS
BASED ON SURFACE OBSERVATIONS AND A PGTW DVORAK INTENSITY ESTIMATE
OF 3.5/4.0. TS 11W IS TRACKING QUICKLY WEST-NORTHWESTWARD ALONG THE
SOUTHWEST PERIPHERY OF THE SUBTROPICAL RIDGE (STR).
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 11W IS FORECAST TO CONTINUE TRACKING WEST-NORTHWESTWARD TO
NORTH-NORTHWESTWARD THROUGH THE FORECAST PERIOD AS IT ROUNDS THE
SOUTHWEST PERIPHERY OF THE STR. THE SYSTEM SHOULD MAKE LANDFALL OVER
CHINA BY TAU 6 AND IS EXPECTED TO WEAKEN RAPIDLY THEN DISSIPATE BY
TAU 36. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT, THEREFORE THERE
IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.
NNNN

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WTPN34 PGTW 300300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 11W (NESAT) WARNING NR 017
03 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
300000Z --- NEAR 25.9N 119.3E
MOVEMENT PAST SIX HOURS - 310 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE, RADAR AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
REPEAT POSIT: 25.9N 119.3E
---
FORECASTS:
12 HRS, VALID AT:
301200Z --- 27.0N 117.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 24 HR POSIT: 340 DEG/ 08 KTS
---
24 HRS, VALID AT:
310000Z --- 28.5N 117.1E
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
300300Z POSITION NEAR 26.2N 118.9E.
TROPICAL STORM 11W (NESAT), LOCATED APPROXIMATELY 128 NM WEST-
NORTHWEST OF TAIPEI, TAIWAN, HAS TRACKED NORTHWESTWARD AT 11
KNOTS OVER THE PAST SIX HOURS. THIS IS THE FINAL WARNING ON THIS
SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE SYSTEM WILL
BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 300000Z IS 20 FEET.REFER TO TROPICAL STORM 07W (NORU)
WARNINGS (WTPN31 PGTW) FOR SIX-HOURLY UPDATES. REFER TO TROPICAL
STORM 12W (HAITANG) WARNINGS (WTPN32 PGTW) FOR SIX-HOURLY UPDATES.//
NNNN

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[youtube]http://www.youtube.com/watch?v=tU8wCl0B28E[/youtube]

Just another day in Taipei.

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Here are some info i got during the passage. Taipei recorded 95 mph wind gust, highest since Super Typhoon Herb since 1996 (100 mph)

Su-ao (120 mph)

Yi-lan (115 mph)

[1900hurricane]

Nesat is still a tropical storm per JMA.

TS 1709 (Nesat)
Issued at 13:10 UTC, 30 July 2017

<Analysis at 12 UTC, 30 July>
Scale -
Intensity -
Center position N25°35' (25.6°)
E117°00' (117.0°)
Direction and speed of movement W 20 km/h (10 kt)
Central pressure 992 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area ALL 110 km (60 NM)

<Forecast for 00 UTC, 31 July>
Intensity -
TD
Center position of probability circle N25°30' (25.5°)
E116°50' (116.8°)
Direction and speed of movement Almost stationary
Central pressure 996 hPa
Radius of probability circle 60 km (30 NM)

<Forecast for 12 UTC, 31 July>
Intensity -
TD
Center position of probability circle N25°25' (25.4°)
E116°35' (116.6°)
Direction and speed of movement Almost stationary
Central pressure 996 hPa
Radius of probability circle 110 km (60 NM)

[1900hurricane]

Now a JMA tropical depression.

TD
Issued at 18:55 UTC, 30 July 2017

<Analysis at 18 UTC, 30 July>
Scale -
Intensity -
TD
Center position N25°00' (25.0°)
E116°00' (116.0°)
Direction and speed of movement WSW Slow
Central pressure 992 hPa