Highest temperature in Seattle on August 9?

Platform comparison

Market context

Seattle-Tacoma International Airport’s highest temperature on 9 August 2026 is the number that settles this market, with the key point for parsers being that the **Weather Underground Daily Observations** table overrides any summary high/low box. In practice, a programmatic watcher should scrape the KSEA daily history page, extract the maximum from the observations feed, and treat later corrections as valid only until the next day’s first datapoint appears, because that is the market’s stated revision cut-off.[1]

A zero-centimarket-style read at 0% YES usually means the crowd is effectively pricing the event as already locked, often because the relevant observation has been published and no alternate settlement band remains. For calibration, Seattle’s late-summer highs are typically in the upper 70s, and nearby reference pages show 9 August around 76–77°F, with daily climate normals and recent August histories clustering close to that level rather than far below it.[2][3][4] For a bot or conditional-order workflow, that means the useful edge is not guessing the weather, but verifying whether the live source has already been fixed, then checking whether the recorded maximum falls into the exact settlement bucket.

The main catalyst to watch is the timing of the final observation and any post-publication revision on Weather Underground, not a forecast update. If you are automating this, the dependency chain is simple: confirm the station ID, poll the daily observations table after the local afternoon peak, and only mark the market as final once the next day’s first datapoint appears or the page stops revising the prior date.[1][5] NWS and forecast pages can help with context on expected warmth, but they do not control settlement here; the settlement source is the Seattle-Tacoma Airport history record itself.[1][6]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Bot UK, which mirrors the Polymarket order book directly.

Resolution & payout

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UK Frequently Asked Questions

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