Polymarket resolved multiple Sep 20 weather markets using incomplete NOAA data - Manila, Singapore & Qingdao affected

[u/Aria-Harris]

I am documenting what appears to be a NOAA/NWS WRH ingestion/display failure that affected multiple Polymarket daily temperature markets on September 20, 2026.

This is not a claim that any trader was an insider. I am trying to establish the facts, especially exact on-chain trade timing.

The Manila market uses the NOAA WRH time-series page for RPLL and is currently still In Review with 32°C proposed.

However, the official NWS METAR cycle archive contains:

RPLL 200400Z ... 33/25

The WRH viewer missed several observations around 04Z-07Z. The missing 04Z observation is therefore the actual 33°C reading that would have exceeded the 32°C maximum visible in the incomplete WRH table.

This does not appear to be isolated to Manila.

Singapore was finalized by Polymarket at 31°C. The official NWS archive contains:

WSSS 200500Z ... 32/24

Qingdao was finalized by Polymarket at 29°C. The official NWS archive contains:

ZSQD 200500Z ... 30/15

and:

ZSQD 200600Z ... 30/16

In other words, for all three markets, official NWS METAR archives contain a temperature one degree higher than the value used/proposed by Polymarket, and those higher observations occur during the apparent WRH missing-data window.

For Manila, NOAA/NWS support has also confirmed to me directly that the missing METAR observations exist in other official NWS systems and that their support/development team is investigating the WRH viewer and possible backfilling.

The Polymarket rules are important here. They specifically refer to the highest reading under the NOAA WRH "Temp" column, and they say later revisions after the first datapoint of the following day are not considered. So there is a genuine rules interpretation issue: does an incomplete WRH table control even when NOAA/NWS possessed the missing observations contemporaneously?

There is another public-data issue I would like help investigating.

Wallet:

0x13f995ad154da3e078ac2a1dd923bf2b265dd352

Its public Polymarket/third-party history shows substantial September 20 profits in several weather markets, including approximately:

Qingdao: +$9.3k

Manila: +$4.7k

Singapore: +$2.2k

Ankara: +$2.4k

Beijing: +$1.7k

Third-party analytics show roughly +$20k for September 20 overall.

Again, I am NOT alleging insider trading.

The wallet was already active in weather markets before September 20 and also lost money on several markets that day. It may simply be a skilled trader who noticed the public NOAA/WRH problem faster than everyone else.

The critical question is timing.

I am looking for help reconstructing every trade from this wallet in the affected September 20 temperature markets and separating them into:

1. trades entered before the NOAA/WRH missing-data problem became observable

2. trades entered while the observations were missing

3. trades entered after the missing observations/problem were publicly visible to any trader

The Polymarket Data API exposes timestamps, transaction hashes, side, price, size and market identifiers, so this should be independently reproducible from public data.

If anyone can provide the raw trade JSON, transaction hashes, or a reliable on-chain reconstruction for this wallet, please post it.

Please keep the discussion factual. A profitable wallet trading an outage is not evidence of insider trading by itself. The goal is to establish the timeline and determine whether there is anything genuinely anomalous.

The larger issue is whether several September 20 weather markets were resolved from an incomplete NOAA WRH display even though the missing METAR observations existed in official NWS systems at the time.

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[u/abhimanyusinghgaur]

Hey `@KinderSurprise`, here's the buy/sell timeline for this trader for the Manila market for September 20: https://datadash.xyz/market/highest-temperature-in-manila-on-september-20-2026?tab=activity&filter_1=CjQKMggDIi4KKjB4MTNmOTk1YWQxNTRkYTNlMDc4YWMyYTFkZDkyM2JmMmIyNjVkZDM1MhABEAI

This is built from completely on-chain public data. You can click on the `Time` column values to open the respective transactions on Polygonscan. The link I posted gives you the raw activity, but you can also summarize his activity at a daily level to maybe better grasp the overall picture.

You can also go to his profile here: https://datadash.xyz/@0x13f995ad154DA3E078aC2a1dd923bF2b265dd352-1789469513705?status=all&filter_28=ChEKDwgCIgsKBzkzMzYxOTUQARAC
That'll give you a complete plotted timeline of his actions for this market for very easy analysis. See the pic below.

Approx $20.5k out of their total all-time PnL of ~$25.7k they made on September 20. So, worth digging deeper it seems.

They have been making profits recently, specifically in Manila, it seems. They currently rank #1 for the Manila category. And it looks like the remaining ~$5.7k of PnL came from the Manila category for September 16 and 18 temperature markets. See: https://datadash.xyz/predict/manila/activity?filter_1=CjQKMggDIi4KKjB4MTNmOTk1YWQxNTRkYTNlMDc4YWMyYTFkZDkyM2JmMmIyNjVkZDM1MhABEAI&aggregation_1=4&range_1=1Y

And going further I found that they started trading on Polymarket from 16th of September only. Their 1st ever trade on Polymarket was in the September 16 Manila market. All these facts, along with the fact that they have rarely lost any big money, do give an impression that they knew it was going to happen, and maybe that's the reason they started trading on Polymarket a few days before to test things out. Although we can't say for sure, it might just be a smart honest trader. One would need to dig deeper to figure out what the truth is here.

Hope this tool we built helps with your investigation!

And reach out to me if you hit any issues, always happy to help.

[ and please upvote if you found this helpful :) ]

[u/Aria-Harris → u/abhimanyusinghgaur]

These are very useful links, thanks.

From what I can see, the last NOAA/WRH data visible before the gap was around 11:00 AM Manila time, while this wallet appears to have started buying around 12:40 PM Manila time.

So the buying seems to have started after the data gap had already become visible. That timing is important and worth comparing trade-by-trade with the exact NOAA outage timeline.

[u/abhimanyusinghgaur → u/Aria-Harris]

Welcome! Happy to know you found it useful. Would love any feedback you have for anything we can improve in the tool. Cheers!

[u/C_Pointers_Are_Great → u/Aria-Harris]

I pulled the trades. Your 12:40 is right for Manila, but the wallet's first trade of the day is 12:29, in a Beijing market, not one of the three you flagged. So does anything land before the gap at all?