Guidance – Forecast Track by Numerical Weather Prediction 2018-07-19T00:00:00Z

FXPQ21 RJTD 190000

RSMC GUIDANCE FOR FORECAST

NAME TS 1810 AMPIL (1810)

PSTN 190000UTC 20.0N 131.3E

PRES 994HPA

MXWD 40KT

FORECAST BY TYPHOON ENSEMBLE PREDICTION SYSTEM

TIME PSTN PRES MXWD

(CHANGE FROM T=0)

T=006 20.4N 131.0E -003HPA 000KT

T=012 20.5N 131.1E -001HPA -001KT

T=018 21.4N 131.1E -003HPA -002KT

T=024 21.9N 130.7E -002HPA -002KT

T=030 22.5N 130.8E -003HPA -003KT

T=036 23.7N 130.4E -001HPA 000KT

T=042 24.9N 129.3E -002HPA 000KT

T=048 26.0N 128.2E -001HPA -001KT

T=054 27.1N 126.9E -002HPA -001KT

T=060 28.1N 125.4E -001HPA -001KT

T=066 29.1N 124.0E -001HPA -003KT

T=072 30.1N 122.8E 000HPA -003KT

T=078 31.0N 121.5E 000HPA -003KT

T=084 31.8N 120.0E +001HPA -003KT

T=090 32.5N 118.5E +001HPA -006KT

T=096 33.1N 117.3E +003HPA -009KT

T=102 33.6N 116.4E +002HPA -011KT

T=108 34.0N 115.6E +002HPA -012KT

T=114 34.4N 114.8E +003HPA -016KT

T=120 35.1N 114.3E +005HPA -017KT

T=126 33.5N 111.4E -002HPA -016KT

T=132 32.1N 108.9E 000HPA -020KT=

Tropical Cyclone Advisory for Analysis and Forecast 2018-07-19T03:00:00Z

WTPQ21 RJTD 190300

RSMC TROPICAL CYCLONE ADVISORY

NAME TS 1810 AMPIL (1810)

ANALYSIS

PSTN 190300UTC 20.3N 131.6E FAIR

MOVE NE 08KT

PRES 994HPA

MXWD 040KT

GUST 060KT

30KT 240NM SOUTH 150NM NORTH

FORECAST

24HF 200300UTC 23.0N 131.4E 50NM 70%

MOVE NNW 09KT

PRES 985HPA

MXWD 050KT

GUST 070KT

45HF 210000UTC 26.4N 127.3E 110NM 70%

MOVE NW 14KT

PRES 975HPA

MXWD 060KT

GUST 085KT

69HF 220000UTC 29.1N 122.0E 140NM 70%

MOVE WNW 14KT

PRES 975HPA

MXWD 060KT

GUST 085KT =

Tropical Cyclone Warning 2018-07-19T03:00:00Z

WTJP32 RJTD 190300

WARNING 190300.

WARNING VALID 200300.

STORM WARNING.

TROPICAL STORM 1810 AMPIL (1810) 994 HPA

AT 20.3N 131.6E SEA SOUTH OF JAPAN MOVING NORTHEAST 08 KNOTS.

POSITION FAIR.

MAX WINDS 40 KNOTS NEAR CENTER.

RADIUS OF OVER 30 KNOT WINDS 240 MILES SOUTH SEMICIRCLE AND 150 MILES

ELSEWHERE.

FORECAST POSITION FOR 191500UTC AT 21.4N 132.3E WITH 30 MILES RADIUS

OF 70 PERCENT PROBABILITY CIRCLE.

990 HPA, MAX WINDS 45 KNOTS NEAR CENTER.

FORECAST POSITION FOR 200300UTC AT 23.0N 131.4E WITH 50 MILES RADIUS

OF 70 PERCENT PROBABILITY CIRCLE.

985 HPA, MAX WINDS 50 KNOTS NEAR CENTER.

JAPAN METEOROLOGICAL AGENCY.=

Guidance – Forecast Track by Numerical Weather Prediction 2018-07-19T00:00:00Z

FXPQ21 RJTD 190000

RSMC GUIDANCE FOR FORECAST

NAME TS 1810 AMPIL (1810)

PSTN 190000UTC 20.0N 131.3E

PRES 994HPA

MXWD 40KT

FORECAST BY GLOBAL MODEL

TIME PSTN PRES MXWD

(CHANGE FROM T=0)

T=06 20.4N 131.2E -003HPA +002KT

T=12 20.7N 131.2E -002HPA +002KT

T=18 21.4N 131.2E -004HPA 000KT

T=24 21.9N 131.0E -003HPA -001KT

T=30 22.7N 131.1E -004HPA -001KT

T=36 23.9N 130.5E -002HPA +001KT

T=42 25.2N 129.6E -003HPA +001KT

T=48 26.5N 128.5E -002HPA 000KT

T=54 27.6N 127.0E -003HPA +001KT

T=60 28.4N 125.4E -002HPA -001KT

T=66 29.3N 123.9E -003HPA -002KT

T=72 30.3N 122.8E -002HPA -001KT

T=78 31.1N 121.5E -002HPA -002KT

T=84 32.1N 120.0E 000HPA -002KT=

Tropical Cyclone Prognostic Reasoning 2018-07-19T00:00:00Z

WTPQ31 RJTD 190000

RSMC TROPICAL CYCLONE PROGNOSTIC REASONING

REASONING NO. 7 FOR TS 1810 AMPIL (1810)

1.GENERAL COMMENTS

TS AMPIL IS LOCATED AT 20.0N, 131.3E. INFORMATION ON THE CURRENT

POSITION IS BASED ON ANIMATED MSI AND SURFACE OBSERVATIONS.

POSITIONAL ACCURACY IS FAIR. THE SYSTEM IS IN A FAVORABLE

ENVIRONMENT FOR DEVELOPMENT UNDER THE INFLUENCE OF HIGH SSTS, HIGH

TCHP, WEAK VWS AND GOOD UPPER-LEVEL OUTFLOW. THIS HAS CAUSED THE

SYSTEM TO DEVELOP OVER THE LAST SIX HOURS. HOWEVER, THE INFLUENCE

OF DRY AIR IS UNFAVORABLE FOR SYSTEM DEVELOPMENT. INFORMATION ON

CURRENT INTENSITY IS BASED ON DVORAK INTENSITY ANALYSES AND

SURFACE OBSERVATIONS.

2.SYNOPTIC SITUATION

THE SYSTEM IS MOVING EAST-NORTHEASTWARD BETWEEN TWO MID-LEVEL

SUB-TROPICAL HIGHS. ANIMATED MSI SHOWS THE SYSTEM HAS A BAND WITH

A CURVATURE SUGGESTING THE CSC. ANIMATED MSI SHOWS GOOD CLOUD

CHARACTERISTICS OF ANTICYCLONIC OUTFLOW. WATER VAPOR IMAGERY SHOWS

DRY AIR AROUND THE SYSTEM. DMSP-F17/SSMIS 89 GHZ MICROWAVE IMAGERY

SHOWS THE SYSTEM HAS A BAND WITH CURVATURE INDICATING THE CSC.

3.TRACK FORECAST

THE SYSTEM WILL MOVE NORTHWARD BETWEEN TWO MID-LEVEL SUB-TROPICAL

HIGHS UNTIL FT24. THE SYSTEM WILL THEN MOVE NORTHWESTWARD ALONG

THE PERIPHERY OF A MID-LEVEL SUB-TROPICAL HIGH UNTIL FT48. THE

SYSTEM WILL THEN MOVE WEST-NORTHWESTWARD ALONG THE PERIPHERY OF A

MID-LEVEL SUB-TROPICAL HIGH UNTIL FT120. THE JMA TRACK FORECAST IS

BASED ON GSM PREDICTIONS, AND REFERENCE TO OTHER NWP MODELS. JMA

TRACK FORECAST CONFIDENCE IS FAIR UNTIL FT72 BUT LOW THEREAFTER

DUE TO SIGNIFICANT DIFFERENCES AMONG NUMERICAL MODEL OUTPUTS.

4.INTENSITY FORECAST

THE SYSTEM WILL DEVELOP UNTIL FT48 DUE TO THE INFLUENCE OF

INTERACTION WITH HIGH SSTS, HIGH TCHP AND WEAK VWS. THE SYSTEM

WILL THEN MAINTAIN ITS INTENSITY UNTIL FT72 DUE TO THE INFLUENCE

OF INTERACTION WITH HIGH SSTS, WEAK VWS AND REDUCED TCHP. THE

SYSTEM WILL THEN WEAKEN DUE TO ITS LANDFALL. THE JMA INTENSITY

FORECAST IS BASED ON GUIDANCE DATA.

=