Highest temperature in Tokyo on August 8?

Platform comparison

Market context

Tokyo is in a familiar mid-summer heat pattern, with forecast highs around the low 30s Celsius and an observed morning reading already in the low 30s at Haneda, which fits the usual August profile rather than an outlier cool spell.[1][2][4] Long-run climate guides and August averages for Tokyo point to daytime maxima near 30–31°C, with muggy conditions and frequent heat peaks, so any market on the day’s top temperature is normally anchored to whether the city merely reaches seasonal norms or breaks above them.[6][11][13] On that basis, a 0% yes price looks less like a view that Tokyo will stay mild and more like a reflection of how tightly the market is framed to a specific temperature bucket on a single date.

The main catalyst for traders is the day’s actual progression at Tokyo Haneda Airport Station, not the broader city forecast banner, because the contract settles on the highest figure in Weather Underground’s Daily Observations table.[4] That means intraday updates, short-lived afternoon spikes, sea-breeze shifts, and any late-reported observation matter more than general forecast headlines; AccuWeather’s same-day forecast and Timeanddate’s hourly profile both imply a hot, settled afternoon, which would keep the highest reading in play if temperatures edge higher than the current morning values.[1][2][14] Weather Underground’s live page already shows conditions in the 30s Celsius, so the key dependency is whether the recorded maximum climbs into the next bracket before the settlement window closes.[4]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Political prediction markets differ structurally from sports betting: thinner liquidity, longer settlement windows, higher sensitivity to single news events. This page shows the live Polymarket quote for Highest temperature in Tokyo on August 8? plus platform attributes for the three reference venues, so you can see at a glance where the deepest market for this question sits.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

UK Frequently Asked Questions

How accurate are political prediction markets?

Historically more accurate than polls. Polymarket's Brier score on US 2024 elections was ~0.11 — better than 538 (~0.14) and every mainstream poll. Markets aggregate information with real skin in the game.

What resolution source is used for elections?

Polymarket defines the source per contract — usually Associated Press (AP Race Call), Reuters or the official electoral commission. The source is stated in contract details before the market opens.

Can prediction markets influence election outcomes?

Markets reflect expectations rather than create them. Studies show public-facing markets can anchor expectations, but don't influence the underlying outcome. Political markets are information, not advocacy.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Are UK election prediction markets available from the UK?

Yes. Betfair Exchange and Smarkets offer UKGC-regulated UK election markets (seat counts, party share, constituency results). Polymarket also lists UK election contracts with deeper global liquidity. Betfair winnings are typically tax-free for UK individuals; Polymarket profits are subject to HMRC CGT.