Highest temperature in Tokyo on August 5?

Platform comparison

Market context

Tokyo is already running hot this morning, and the question now is how far the afternoon maximum can climb before the day cools. The latest hourly forecast points to temperatures rising from the high 20s Celsius before dawn to around 88°F, or about 31°C, in the early afternoon, with no precipitation expected[7]. That leaves the market anchored to a fairly tight late-summer range rather than an extreme outlier.

The 0% implied probability for the YES outcome is consistent with Tokyo’s August climate, where average maximums are usually around 31°C and highs above 30°C are common but prolonged mid-30s spikes are not the norm[9][11]. At Haneda specifically, the first two August 2026 daily observations already sit in the mid-30s for the prefecture’s coastal stations, while Tokyo city itself has also posted readings in the mid-30s earlier this month, underscoring that the market is about the day’s peak rather than the morning baseline[2]. Recent Tokyo day-ahead markets have also resolved in the high-20s to mid-30s Celsius band, reinforcing how tightly summer outcomes cluster around a few plausible brackets[18].

The main catalysts are the updated midday forecast, any sudden shift in cloud cover or sea-breeze strength over the Tokyo Bay area, and the actual Haneda observation sequence used by the resolution source. Japan is in an elevated summer-heat regime this year, with Reuters reporting record heat elsewhere in the country and authorities warning about continued extreme temperatures[13]; that broader pattern supports upside risk if a hot air mass persists into the afternoon. Traders should watch whether the forecast lifts above 31°C, because a small move in the top-end forecast can matter more than the overnight readings in a market settled on the day’s highest temperature[7][13].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Tokyo on August 5? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Prediction Today, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Prediction Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.