Highest temperature in Atlanta on May 22?

Platform comparison

Active sub-markets

Market context

Polymarket is pricing the Hartsfield-Jackson Atlanta airport high for 22 May almost entirely into the lowest bucket, with the crowd giving 0% to a YES outcome in the market’s current state. The contract settles in USDC on Polygon via conditional tokens, and the relevant level is the day’s final recorded maximum at KATL as shown on Wunderground once the historical data are complete.

That pricing is consistent with the broader seasonal pattern in Atlanta rather than an extreme forecast call. Late May highs in the city commonly sit in the low-to-mid 80s Fahrenheit, and recent market references point to a forecast around 83–85°F under mostly cloudy skies with scattered afternoon showers. AccuWeather’s May outlook also keeps daily highs mostly between the upper 70s and upper 80s, while WeatherSpark notes that Atlanta’s May daily highs typically rise from about 76°F to 83°F and only rarely push much above 90°F. In that context, the shortest path to the upper buckets would be a stronger-than-expected warm-up and a lack of cloud or rain suppression.

For traders, the main inputs are the National Weather Service forecast updates, airport observations through the day, and whether showers or thunder are timed for the afternoon peak heating window. The market’s settlement source is the Wunderground history page for KATL, so the final print matters more than any citywide estimate or nearby station reading. With the settlement window ending at noon UTC, the contract is effectively tied to the airport’s completed daily record rather than any intraday move in the futures-like market price on-chain.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Atlanta 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.

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.