Highest temperature in Seoul on July 9?

Platform comparison

Market context

Seoul is heating up fast as temperatures surged to 37.1°C on 8 July, the highest recorded July temperature since national data collection began in 1908, prompting meteorologists to warn that this summer could become South Korea’s hottest yet with peaks potentially exceeding 40°C[6]. This extreme spike, occurring just 24 hours before the settlement window, has shifted the real-world outlook from typical monsoon dampness to a record-breaking heatwave, directly explaining why the crowd-implied probability for the current temperature range sits at 0%[6].

Historically, Seoul’s July averages hover around 26–28°C, with highs rarely breaching 32°C unless during intense heatwaves, making the current 37.1°C reading an outlier that frames the 0% probability as a rational market reaction to unprecedented conditions[5][6]. Comparable cases from the early 2000s show similar deviations only during prolonged El Niño events, but the speed of this rise—jumping from monsoon lows to record highs in days—suggests a unique atmospheric driver rather than a seasonal norm[6].

Traders should monitor the Korea Meteorological Administration’s short-range forecasts for continued rain probability and wind shifts, as slight precipitation could temporarily cool the air but is unlikely to offset the overarching heat trend[7]. Recent reports confirm temperatures are climbing to 30–32°C with strong sunshine all weekend, indicating the heatwave will persist through 9 July, making further spikes above 40°C a credible risk if the current trajectory holds[9]. The Sinchon Water Gun Festival in late July may offer localized cooling, but its timing is irrelevant to the 9 July settlement, leaving the heatwave as the dominant catalyst[4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seoul on July 9? 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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

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's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.