WPAC: HAISHEN - Post-Tropical

[Highteeld]

Western eyewall looking better and better

[aspen]

My 110 kt 00Z forecast might be a little low if it really starts kicking here the next six hours.

The convection over the western eyewall has intensified a lot over the last hour, so it might be ready to RI

https://i.imgur.com/W7ds45I.png

https://i.imgur.com/9B0uUaD.png

I was originally very skeptical of the JTWC’s official forecast calling for a Super Typhoon in 24 hours; it seemed very aggressive for a system struggling to complete an EWRC. However, now that the inner eyewall is gone and the new eye is rapidly taking shape...maybe 130 kt is a little low.

[Highteeld]

Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 03 SEP 2020 Time : 173000 UTC
Lat : 21:12:35 N Lon : 135:48:00 E


CI# /Pressure/ Vmax
6.1 / 939.9mb/117.4kt


Final T# Adj T# Raw T#
6.1 6.7 6.7

Estimated radius of max. wind based on IR : 16 km

Center Temp : +4.2C Cloud Region Temp : -75.1C

Scene Type : EYE

[Highteeld]

My 110 kt 00Z forecast might be a little low if it really starts kicking here the next six hours.

The convection over the western eyewall has intensified a lot over the last hour, so it might be ready to RI

https://i.imgur.com/W7ds45I.png

https://i.imgur.com/9B0uUaD.png

I was originally very skeptical of the JTWC’s official forecast calling for a Super Typhoon in 24 hours; it seemed very aggressive for a system struggling to complete an EWRC. However, now that the inner eyewall is gone and the new eye is rapidly taking shape...maybe 130 kt is a little low.

The eye is very large, probably 50 nm in diameter. It could contract some in the next 24 hours and make the Cat 5 possibilities increase

[Highteeld]

Finally the Himawari target has moved to Haishen

[Highteeld]

Major improvement over the last hour; would expect RAW T numbers over 7.0 soon

[aspen]

This is easily a 115 kt Cat 4. Quite an improvement since the last advisory.

[Cunxi Huang]

I would say 120 kt based on a blend of RJTD/T5.5, PGTW/T6.5, and CIMSS-ADT/T6.1.
Also current SATCON supports an MSLP down to 932 hPa. Knaff and Zehr w-p relationship would support an intensity up to 125 kt.

CURRENT ESTIMATE
Date (mmddhhmm): 09031638
SATCON: MSLP = 932 hPa MSW = 129 knots
SATCON Member Consensus: 122.0 knots
Pressure -> Wind Using SATCON MSLP: 130 knots
Distance to Outer Closed Isobar Used is 205 nm
Eye Size Correction Used is 10.7 knots Source: IR

[Highteeld]

This is easily a 115 kt Cat 4. Quite an improvement since the last advisory.

Yeah. The last hour has been pretty spectacular

[Highteeld]

..............Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 03 SEP 2020 Time : 180000 UTC
Lat : 21:12:35 N Lon : 135:41:59 E


CI# /Pressure/ Vmax
6.2 / 937.7mb/119.8kt


Final T# Adj T# Raw T#
6.2 6.7 6.7

Estimated radius of max. wind based on IR : 17 km

Center Temp : +11.6C Cloud Region Temp : -74.7C

[Highteeld]

JTWC not screwing around

11W HAISHEN 200903 1800 21.2N 135.8E WPAC 125 934

[ElectricStorm]

JTWC not screwing around

11W HAISHEN 200903 1800 21.2N 135.8E WPAC 125 934

Finally a storm where they may not lag behind. This looks like a lock to become the first super typhoon of the season

[NotoSans]

JMA's forecast track brings it VERY close to Minamidaitojima, so we may be able to get some valuable observations regarding the storm's peak intensity.

[Dave C]

Small island due east of Okinawa has a weather station and should be in the crosshairs . It's name is MinamiDaito and has minor population I believe.

[Highteeld]

Getting some Mangkhut vibes (W ring is over 100 miles thick on the north side)

[NotoSans]

Won’t be surprised to see a category 5 by 00Z at this rate.

[Cunxi Huang]

Whoopsie EC 12Z+24h 899 hPa

WP, 11, 2020090312, 98, EMDT, 24, 225N, 1335E, 122, 899, , 34, NEQ, 198, 182, 140, 185, 0, 0, 25
WP, 11, 2020090312, 98, EMDT, 24, 225N, 1335E, 122, 899, , 50, NEQ, 100, 94, 66, 94, 0, 0, 25
WP, 11, 2020090312, 98, EMDT, 24, 225N, 1335E, 122, 899, , 64, NEQ, 50, 49, 44, 44, 0, 0, 25

[Highteeld]

2020SEP03 190000 6.5 930.9 127.0 6.5 6.9 7.0 1.3T/6hr OFF OFF OFF OFF 14.89 -76.16 EYE 27 IR 76.3 21.40 -135.66 ARCHER HIM-8 25.7

[ElectricStorm]

2020SEP03 190000 6.5 930.9 127.0 6.5 6.9 7.0 1.3T/6hr OFF OFF OFF OFF 14.89 -76.16 EYE

Well that escalated quickly

[aspen]

Getting some Mangkhut vibes (W ring is over 100 miles thick on the north side)

https://i.imgur.com/UIJxz9G.png

It now seems inevitable that Haishen will join the Category 5 “Ha”-named WPac storms — Haiyan, Hagupit, Haima, Hagibis, and Halong. If it keeps that W ring with moderate amounts of CMG, it’ll be an easy 150-155 kt at the minimum.