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Market for Koinu, go have a look!

Based on the latest JTWC wind speed reading at 55kt, as well as data from local time 8am from HKO and CWA, Koinu has not reached the required strength for YES. Therefore, the market is now resolved as NO.

Thank you very much for your participation, and especially for @parhizj for providing such informative, enriching and detailed analyses of potential candidates along the way!

In a day I am likely to make a Koinu market (probably about its max strength, whether it will land in Taiwan or its impact on Hong Kong, but other ideas are welcome as well). Please stay tuned!

The market has now closed. At 1500Z / GMT+8 11:00pm, JTWC still denotes Koinu as a Tropical Storm, thus not fulfilling the conditions for YES outlined in the description. Weather agencies in Taiwan and Hong Kong are still showing Koinu as a TS / TS-equivalent, though they are data from local time 8pm on the 30th.

As no objection to the original closing time has been noted so far, I am leaning towards keeping with the closing time as the original one, and treat the closing time as cut-off time for the criterion. I will seek data points nearest to this time for judgment, though so far the resolution is apparently going to be NO.

I am going to wait until morning on October 1 in the region (approximately 6-8 hours later) for the regional agencies report the next tick of data. Meanwhile, you are still welcome to give comments regarding the resolution.

Last JTWC&JMA (21Z updates) have the most recent observed intensity as 45kt. I found a SMAP measurement of ~50kt earlier today. Looks like the wind speeds might be estimated as high as 50-60 kt range for 00Z, as SATCON has it at about ~55kt for the moment and it is trending upwards (multiplatform experimental CIRA has it at 50kt).

The next JTWC warning with intensity numbers is in ~4 hours (03Z).

@parhizj CWA and HKO at local times 8am are still reporting TS strength, but yes, I am going to wait for the next JTWC warning in about an hour for full clarity.

@SarkanyVar Its subject to change before the warning but it looks like it might be 55kt from the tcvitals

https://hurricanes.ral.ucar.edu/repository/data/bdecks_open/2023/bwp142023.dat

WP, 14, 2023100100,   , BEST,   0, 174N, 1295E,  55,  991, XX,  34, NEQ,   75,  100,   95,   40, 1006,  330,  35,   0,   0,   W,   0,   X, 315,   8,      KOINU, M,   ,    ,     ,     ,     ,     ,      TCGP EXTRA DATA, WP142023, JTWC, NCEP_TCVITALS, 

@SarkanyVar It's out now: 55kt

https://www.metoc.navy.mil/jtwc/products/wp1423web.txt

Forecast to become a hurricane in 12 hours. 😅 Looks like that RI concern I had from earlier was pretty close and warranted if they are forecasting a typhoon in 12 hours:

WTPN31 PGTW 010300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL STORM 14W (KOINU) WARNING NR 007//
RMKS/
1. TROPICAL STORM 14W (KOINU) 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:
   010000Z --- NEAR 17.4N 129.5E
     MOVEMENT PAST SIX HOURS - 320 DEGREES AT 08 KTS
     POSITION ACCURATE TO WITHIN 030 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
                            100 NM SOUTHEAST QUADRANT
                            095 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
   REPEAT POSIT: 17.4N 129.5E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   011200Z --- 18.5N 128.7E
   MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            120 NM SOUTHEAST QUADRANT
                            130 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 325 DEG/ 06 KTS
    ---

@parhizj That was a close call indeed!

@parhizj Koinu is a typhoon now at 09Z. So close!

TYPHOON 14W (KOINU) WARNING NR 008    
   UPGRADED FROM TROPICAL STORM 14W
   01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   010600Z --- NEAR 17.9N 129.0E
     MOVEMENT PAST SIX HOURS - 315 DEGREES AT 07 KTS
     POSITION ACCURATE TO WITHIN 015 NM
     POSITION BASED ON CENTER LOCATED BY A COMBINATION OF 
     SATELLITE AND RADAR
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT

There are still about 7 hours till the closing of this market. I originally set this to adhere to the end of October in the NW Pacific according to the GMT+8 timezone.

But due to the possible uncertainties with Koinu's development which can potentially affect the market resolution, I think there is a need to clarify whether the traders agree or disagree that:

1. The market trading should be closed according to the original closing time, or whether it should be extended until the end of October in every part of the world.
2. The cut-off time for the resolution criteria should be the same as the closing time, or whether it should be extended until the end of October in every part of the world.

Please kindly let me know in the comments what you think.

@SarkanyVar I don't predict the closing time offset will affect the resolution based on the current probabilities and forecast. I am still a bit confused about the closing time as it appears to other people... to me it appeared in my time zone (EDT) at midnight (+04 UTC). I think either the local timezone you mentioned (GMT+8) or UTC makes the most sense when creating the question but I am really ambivalent for this question for how you update the resolution time.

@parhizj To be honest, I never quite figured out the exact timezone specification on Manifold. A while ago for the sake of another market, I fiddled with the local settings, and I think for each individual it shows the time according to the timezone on your system, but the timezone used is not explicitly stated.

When someone sets the closing date of a market, the exact time used is most likely also set at the end of the day according to the system timezone. So if I wanted to set the market to end at Sep 30 23:59 at GMT+8, I would have to set my system to the +8 timezone first. A bit unwieldy, to be honest.

@SarkanyVar I searched the discord and it looks like it is always displayed/created according to the users time zone... so as the creator you could just add the hours to whatever your local timezone is.

For instance since my timezone is currently UTC-04 right now, if I wanted it to close at 00:00 UTC+08, I would set it at 12:00 my local time. I think I've done this for one of my own markets but I tend to forget these details. However, if you want it to resolve per a local time zone (and not just UTC offsets) then you have to be careful about things like daylight savings time.

JTWC and JMA updates still do not predict hurricane strength by resolution time, but there is a lot of uncertainty in both track and uncertainty due to the stage of development, complex scene, and uncertainty in the position and from the intensity of the storm winds.

The JTWC prognostic reasoning is interesting to read after looking at the complex scene from the imagery earlier today, quoting:

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED CIRA PROXY VISIBLE SATELLITE IMAGERY DEPICTS A COMPLEX SCENE 
OF DEEP CONVECTION FRACTURED INTO TWO PRIMARY MASSES. BEST TRACKING 
HAD BEEN ALONG THE SOUTHEASTERN MASS, HOWEVER IT HAS BEEN GRADUALLY 
DECLINING WHILE THE CONVECTION TO THE NORTHWEST HAS BEEN IMPROVING IN 
APPEARANCE. HOWEVER, BOTH APPEAR TO BE IN AN ENVELOPE OF A BROAD LOW 
LEVEL CIRCULATION CENTER (LLCC). THE FOOTPRINTS OF THE MOST RECENT 
ASCAT PASSES MISSED THE LLCC, BUT SUGGEST EITHER AN ELONGATED LLCC, OR
THE POSSIBILITY OF TWO DISTINCT LLCCS. NO OTHER RECENT MICROWAVE
IMAGERY IS AVAILABLE TO HELP REFINE THE INITIAL POSITION, WHICH WAS
ASSESSED WITH LOW CONFIDENCE BASED ON THE LARGER LOW LEVEL BANDING
OBSERVED IN THE PROXY VISIBLE IMAGERY, AND SERVES AS A CENTRAL POINT 
OF THE SCENARIOS DESCRIBED ABOVE. THIS POSITION IS IN AGREEMENT WITH 
THE GFS AND ECMWF ANALYZED CENTERS. ALTHOUGH THE ASCAT PASSES INDICATE 
THE PRESENCE OF 35 KNOT WINDS, THESE ARE UNDER THE DEEP CONVECTION TO 
THE NORTHWEST AND APPROXIMATELY 100 NM FROM THE ASSESSED CENTER. THE 
INITIAL INTENSITY WAS ASSESSED AT 30 KNOTS GIVEN THE OVERALL POOR 
ORGANIZATION OF THE LOW LEVEL VORTEX AND IN AGREEMENT WITH AGENCY 
DVORAK FIXES FROM T1.5 TO T2.0, AS WELL AS AVAILABLE OBJECTIVE 
INTENSITY ESTIMATES. CIMSS WIND SHEAR ESTIMATES ARE GENERALLY 
FAVORABLE AT 10 TO 15 KNOTS. TD 14W IS TRACKING WESTWARD UNDER THE 
INFLUENCE OF MID-LEVEL SUB-TROPICAL RIDGING (STR) TO THE NORTH, WITH 
MODERATE EQUATORWARD OUTFLOW.

Updates to CWA, JMA, and JTWC forecasts show nothing warranting concern for this question

As mentioned, model guidance from 00z shows the increased agreement in the models and intensity below 60 kt by resolution time.

Edit: Looking at the late guidance from 06 it is roughly on schedule actually for TS intensity as some of the models do show speeds that high (the time resolution isn't that high). Timestamp for the measurement of ASCAT is 13:02 UTC and the models other than AVNO (GFS) do have it at TS intensity at around time...

recent partial ASCAT shows some 35-40 kt winds

CIRA (experimental) satellite product puts it it at 39kt

CIMSS now has RI probabilities for 14W

https://tropic.ssec.wisc.edu/real-time/ai-ri/wp142023_history.html

4% for AI-RI, and 15% for AI-RI Consensus for RI-36H +45 kt (from 12UTC of 25kt to push it into 70kt by Oct. 1 00 UTC) (nothing more fine grained than that for now). This gives me some relief that the market probability isn't too far off as compared to the previous CIRA RI probabilities.

Per JMA, now TS Koinu (35 kt)

https://www.jma.go.jp/bosai/map.html#6/20.231/125.969/&typhoon=TC2316&contents=typhoon&lang=en

😦

Latest RIPA consensus (CIMSS) shows some slightly possibilities for resolving YES: 18UTC + 36 hours (Oct 1, 06 UTC). It is useful to reference the paper for RIPA in this case (https://journals.ametsoc.org/view/journals/wefo/33/3/waf-d-18-0012_1.xml), which says for the latest run of RIPA, 45kt RI, LRE has better reliability, and that in the verification, a forecast probability of 51% had an observed probability of ~30% (this is similar to the AI in RIPA consensus value of 28%). Hopefully, the next RI run for 00Z and models guidance 18Z should show the timeline clearer.

That the question closes at midnight EDT (which is Oct 1, 04 UTC) means this one data point is of concern for this question resolving YES...

Updated JMA/CWA/JTWC forecasts (18Z)... none of them show RI on this specific time frame to cat.1, so I would like to defer to them for the most likely scenario... however the JTWC has stated low confidence in the intensity forecast for the next 72 hours and forecasting RI is hard.

An Operational Rapid Intensification Prediction Aid for the Western North Pacific

Abstract This work describes tropical cyclone rapid intensification forecast aids designed for the western North Pacific tropical cyclone basin and for use at the Joint Typhoon Warning Center. Two statistical methods, linear discriminant analysis and logistic regression, are used to create probabilistic forecasts for seven intensification thresholds including 25-, 30-, 35-, and 40-kt changes in 24 h, 45- and 55-kt in 36 h, and 70-kt in 48 h (1 kt = 0.514 m s−1). These forecast probabilities are further used to create an equally weighted probability consensus that is then used to trigger deterministic forecasts equal to the intensification thresholds once the probability in the consensus reaches 40%. These deterministic forecasts are incorporated into an operational intensity consensus forecast as additional members, resulting in an improved intensity consensus for these important and difficult to predict cases. Development of these methods is based on the 2000–15 typhoon seasons, and independent performance is assessed using the 2016 and 2017 typhoon seasons. In many cases, the probabilities have skill relative to climatology and adding the rapid intensification deterministic aids to the operational intensity consensus significantly reduces the negative forecast biases.

None of the official forecasts (JTWC, CWA, JMA) are forecasting RI, but interpreting latest RI suggests about a 30% chance of becoming a hurricane by Oct. 1, 12 UTC (using 40kt intensity RI25 and taking 30% (taking observed probability from verification bin) of predicted 57% LRE; RI-AI has it above 20%).

JTWC also just upgraded it to a TD and has forecast the intensity as a TS by Oct. 1.

https://www.metoc.navy.mil/jtwc/products/wp1423web.txt

Late guidance 06Z from the four models agree TD-TS intensity by Oct. 1

@parhizj Intriguing punctuation to a very calm September in NW Pacific. If 14W becomes Koinu only in October (or never), it would be the least cyclonically active September in the region since CWA's records began in 1958.

@SarkanyVar By what metric? # storms ?

@parhizj I believe so. Citing a CWA meteorologist below:

https://udn.com/news/story/7266/7473439

獨／9月至今只有海葵颱風生成 氣象署：可能創歷史新低 | 聯合新聞網

中央氣象署表示，菲律賓東方海面靠近關島一帶區域目前有一個熱帶擾動低壓，未來有發展為熱帶性低氣壓，最快可能在中秋連假期間生...

Rough translation:

Forecaster Lin Dingyi of CWA said that if the tropical disturbance develops into Typhoon Koinu, it is forecast to approach Taiwan or pass through the Bashi Channel next Monday and Tuesday. However, in the past, the paths of autumnal cyclones have been quite variable, and how close it is to Taiwan still depends on the strength of the Pacific high, therefore there is still great uncertainty.

Lin Dingyi also said that in previous years, there would be an average of 5 or 6 typhoons (see note) in September. So far there was only Typhoon Haikui (also see note) in early September, which is much lower than the average. If Koinu only develops in October, it means that there was only one typhoon in September this year, the lowest number since records began in 1958; if Typhoon Koinu forms within September, there would be a total of two typhoons, also the lowest number since 1986.

---

Note: CWA's terminology is a bit different from the other agencies. They call TSs 'mild typhoons' (輕度颱風), so sometimes TSs are also referred to as typhoons in Taiwan. I believe therefore the average number of 5 to 6 refer to named storms, including mild typhoons / TSs.

But here I do think within the context of records, they mean typhoons as in those reaching Cat-1 equivalent strength or above, because they seem to be discounting Yunyeung which also reached TS level. Haikui reached typhoon strength on Sep 1 so it counts as a September typhoon, just barely.

For interest, I also checked the ACE records of NW Pacific. September 2023 ACE thus far is (212.3 - 203.1) = 9.2. From historical ACE September records of NW Pacific from 1950-2021, the lowest September ACE is 5.3 in 1960, second lowest is 10.3 in 1973. So while to-be Koinu might add to the final ACE number, it still speaks to a September that is towards the very calm end of the spectrum.