WPAC: CHOI-WAN - Post-Tropical

[1900hurricane]

Looks like guidance is finally starting to come into better agreement and just have a better handle in general following multiple days where the center ended up propagating more downshear than solutions indicated. I talked a bit about that and the importance of human forecasters in a pair of recent tweets.

 https://twitter.com/1900hurricane/status/1399855216351186947



 https://twitter.com/1900hurricane/status/1399855219291340801

[mrbagyo]

Radar (as always)

Looks like it's already in the Sibuyan Sea

[JW-_-]

[R o x]

What are the chances this storm will come deliver water to Taiwan ?

[doomhaMwx]

What are the chances this storm will come deliver water to Taiwan ?

Taiwan still in a drought? Doesn't look like Choi-wan itself will bring much rain to Taiwan, but it could help trigger a promising rainfall event behind it.

[1900hurricane]

BIg track errors for both JTWC and JMA (RJTD) with Choi-wan. Neither agency really picked up the downshear center propagation.



Methodology compares the forecast to the verifying position in the b-deck, so JMA will have larger error at initialization if they have a slightly different center position than JTWC. Errors are in nm.

[mrbagyo]

Doesn't look that bad now

[JW-_-]

sheared 1/2 storm.


https://www.jma.go.jp/bosai/map.html#5/ ... rval=short

[R o x]

What are the chances this storm will come deliver water to Taiwan ?

"Taiwan still in a drought? Doesn't look like Choi-wan itself will bring much rain to Taiwan, but it could help trigger a promising rainfall event behind it."

Thanks for the heads up, Imran !
Big parts of Taiwan still suffers from a terrible lack of water; lakes almost dried up practically everywhere, except those in the north of the country.
Turns out, at least on our side of the land, we are totally depending on typhoons to bring water
Here in Toufen/Jhunan we're now on a two day per week water-off regime that could be increased any moment if the water ain't coming very soon.
Nature also suffering immensely, trees dying, declining fauna all thanks to fuppi'n climate change

[JW-_-]

Meiyu front's usually always delivers precip over Taiwan like clockwork annually.

[Meow]

JMA now expects a landfall.



<Analysis at 21 JST, 2021/06/03>
Intensity/Category Tropical Storm
Center Position 18.5N 118.2E
Direction and speed of movement NNW 20km/h (10kt)
Central pressure 1000hPa
Maximum wind speed near center 20m/s (40kt)
Maximum wind gust speed 30m/s (60kt)
≥ 30-kt wind area ALL 165km (90NM)
<Forecast for 09 JST, 2021/06/04>
Intensity/Category Tropical Storm
Center Position 20.2N 118.8E
Direction and speed of movement NNE 20km/h (11kt)
Central pressure 1002hPa
Maximum wind speed 18m/s (35kt)
Maximum wind gust speed 25m/s (50kt)
Radius of probability circle 85km (45NM)
<Forecast for 21 JST, 2021/06/04>
Intensity/Category Tropical Depression
Center Position 22.4N 120.6E
Direction and speed of movement NE 20km/h (12kt)
Central pressure 1004hPa
Radius of probability circle 120km (65NM)

[mrbagyo]

[JW-_-]

That 12z run was seeing a healthy drink in is forecast.




Bom

[JW-_-]

00z GFS thinking. So yeah looking like the heavens will be opening up.

[Hayabusa]

Choi-wan may be crap throughout but I am amazed at its tenacity maintaining as a TS and models clearly failed this one in track.

[Iceresistance]

Choi-wan may be crap throughout but I am amazed at its tenacity maintaining as a TS and models clearly failed this one in track.

That is holding on for dear life!