Highest temperature in NYC on July 21?

Platform comparison

Market context

On 21 July 2026, the highest temperature recorded at LaGuardia Airport will fall into one of several defined ranges. Polymarket currently prices all temperature bands at 0% YES, reflecting the market's nascent state roughly eighteen months before settlement. The contract resolves using Wunderground's historical data for that specific date, with settlement occurring at 12:00 UTC on the day itself. Traders entering positions now face substantial uncertainty: the conditional token structure on Polygon means capital is locked until resolution, with payouts denominated in USDC reflecting whichever temperature band ultimately contains the day's peak reading.

New York City's July temperatures exhibit consistent patterns across decades. Historical data shows LaGuardia's July highs typically range between 82°F and 88°F, with extreme readings occasionally reaching into the low 90s during heat waves. The 1999 heat wave produced readings above 95°F, whilst cooler Julys have settled around 80°F. The 2023 summer saw elevated temperatures across the Northeast, though July specifically remained within normal bounds. These historical distributions provide the baseline against which traders should calibrate their probability assessments across the available temperature bands.

Climate forecasting for summer 2026 remains speculative at this distance, though seasonal outlooks from NOAA typically emerge in June 2026. El Niño or La Niña conditions developing through early 2026 could influence Atlantic weather patterns. Urban heat island effects around LaGuardia itself—the airport's concrete and tarmac infrastructure—consistently elevate readings relative to surrounding areas. Traders should monitor spring 2026 climate indices and any emerging consensus on summer conditions, as these will sharpen probability estimates closer to settlement.

Methodology

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

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?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

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.