Highest temperature in London on May 26?

Platform comparison

Active sub-markets

Market context

On 26 May 2026, the highest temperature recorded at London City Airport will determine which range this market settles into. The current 0% YES probability reflects the market's assessment of a specific temperature threshold being reached on that date. Polymarket prices this contract via USDC on Polygon, with conditional tokens representing discrete temperature bands. Traders are currently pricing out the upper ranges entirely, suggesting consensus around cooler conditions or uncertainty about which threshold the market is actually testing.

London's May temperatures historically cluster between 15–22°C, with occasional peaks into the mid-20s during settled high-pressure systems. The Met Office's 30-year climate averages show May as a transitional month where warm spells are possible but not dominant. Recent May records for the capital have seen highs of 26–28°C during anomalous warm events, though these remain outliers. The 0% pricing suggests traders expect conditions well below historical May extremes, or the market may be testing an unusually high threshold that rarely materialises in late spring.

The UK's weather forecast reliability extends reliably to about ten days ahead; traders should monitor the Met Office and BBC Weather from mid-May for high-pressure system positioning over the British Isles. Any Atlantic blocking pattern developing in late April or early May could shift expectations materially. The settlement window closes at 12:00 UTC on 26 May, so Wunderground's final recorded high at London City Airport—the official resolution source—will be locked in by early afternoon, leaving minimal time for late-day surprises to influence outcomes.

Methodology

This page reviews Highest temperature in London on May 26? across five venues. We show live odds for Polymarket-based markets (sourced from the Polygon order book); for other venues we list platform attributes, since the comparable contracts are not exposed via a public API on every venue. Every CTA points at PolyGram — the application we operate, where you trade directly against 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?

On PolyGram, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

PolyGram is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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 it cost to trade on PolyGram?

Zero. PolyGram routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.