Highest temperature in Seoul (Incheon) on August 12?

Platform comparison

Market context

Seoul's August weather patterns show consistent heat during the summer monsoon season, with daily highs typically ranging between 28–32°C at Incheon International Airport, the official measurement station for this market. The 0% crowd probability reflects either extreme confidence in a specific temperature band or minimal trading activity; comparison platforms like Kalshi and Betfair often show wider probability distributions on regional weather markets due to their larger trader bases, whereas Polymarket's smaller liquidity pools can produce sharper, more volatile odds movements on niche outcomes. The resolution mechanism—drawing from Weather Underground's Daily Observations table rather than summary figures—introduces a technical distinction that traders on different platforms may interpret differently, particularly if secondary sources report conflicting highs.

Historical August data for Incheon shows that temperatures above 33°C occur roughly once per decade during this month, whilst readings below 26°C are exceptionally rare. The 2023 and 2024 summer seasons saw peak temperatures of 31–32°C in mid-August, establishing a baseline for assessing the current market's implied range. Traders should monitor the Korea Meteorological Administration's seasonal forecasts and any tropical cyclone activity in the Western Pacific, as typhoons approaching the Korean peninsula in early August can suppress temperatures significantly. The settlement window closes at midday UTC on 12 August 2026, creating a hard deadline for measurement; platforms differ on how they handle partial-day closures, with some accepting final readings at market close and others requiring full 24-hour observation periods.

Methodology

We read Highest temperature in Seoul (Incheon) on August 12? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). On-chain settlement clears in minutes — the fastest payout path of the four.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Robinhood Prediction Markets offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.