Highest temperature in NYC on June 21?

Platform comparison

Active sub-markets

Market context

At LaGuardia Airport on 21 June, the market will pay out according to the *highest* Fahrenheit temperature recorded on Weather Underground for that day, not the forecast or the daily average. In simple terms, a **YES** share wins if the final maximum falls in the range attached to that outcome, while a **NO** share does not; the contract only settles once the next day’s first reading has been published, because that is when the day’s observations are treated as complete.[1][2]

The current crowd price of **0% YES** says traders are assigning almost no chance to the selected temperature band, which is a useful reminder that these contracts are range-specific, not a view on whether New York will be hot in general. LaGuardia’s June climate normal for maximum temperature is 83°F, with a record June maximum of 98°F, so a very warm day is not unusual even if the exact band needed for a YES outcome is narrow.[7] More broadly, June highs in New York often sit in the 70s and 80s, with occasional spikes higher, so the market is best read as a judgement on one particular interval rather than on “hot versus cool” alone.[6][9]

Traders should watch the weather pattern on the day itself: cloud cover, humidity, wind direction, and any heat advisory can all affect the afternoon peak, which is usually what sets the daily maximum. For a market like this, the key dependency is the published LaGuardia history table on Weather Underground, because the resolution uses that source’s final daily high and can change if late data revisions appear before the next day’s first datapoint.[1][2]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to Prediction Market UK, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

On Prediction Market UK, 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 Prediction Market UK?

Zero. Prediction Market UK 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.