Highest temperature in Buenos Aires on May 22?

Platform comparison

Active sub-markets

Market context

Polymarket is effectively pricing this Buenos Aires airport temperature contract as a dead cert on the “no” side, with the market showing 0% YES and the outcome to be settled from the highest reading recorded at Minister Pistarini Intl Airport on 22 May. Because the resolution is based on the day’s finalised Wunderground history entry, the key number is the single highest observed Celsius value before the settlement window closes at 12:00 UTC. In practical terms, traders are holding conditional tokens on Polygon and posting USDC against a very narrow weather range, so any late morning spike in Ezeiza would matter more than the overnight low.

The seasonal backdrop is fairly cool for Buenos Aires in late May. Climate averages put daily highs around 60°F to 61°F, or roughly 15°C to 16°C, with lows in the low 50s°F. World Weather Information Service shows a forecast for 22 May of 7°C to 13°C, which is below the longer-run May norm and suggests a modest ceiling rather than a warm afternoon. Comparable May market pricing on Polymarket has also been concentrated around low-teens outcomes: recent Buenos Aires temperature markets for 20 May and 21 May were already dominated by 14°C and 12°C respective frontrunners, with alternative brackets priced at 0%.

For traders, the main catalysts are the morning forecast updates and any last-minute shift in cloud cover, rain, or wind direction at Ezeiza, rather than broader citywide conditions. Wunderground’s final airport history page is the settlement source, so the live airport reading matters more than headlines about central Buenos Aires. The latest public forecast cited by the World Weather Information Service points to partly cloudy conditions and a 13°C daytime high, which is consistent with a limited upside case and helps explain why the market is sitting at 0% YES despite the contract still needing a final observed maximum to settle.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Buenos Aires on May 22? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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.

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 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.