Highest temperature in NYC on July 20?

Platform comparison

Market context

The market resolves to the highest temperature recorded at LaGuardia Airport on 20 July 2026, with settlement in USDC and a 0% crowd-implied probability for any outcome outside the frontrunner range. Polymarket data shows the 82–83°F range currently commands 100% probability, effectively pricing out all other temperature bands including 69°F or below at 0% [1]. This extreme consensus suggests traders view the historical heatwave context as decisive for this specific date.

July 2026 saw a record-breaking heatwave across the East Coast, with NYC, DC, and Atlantic City simultaneously shattering long-standing temperature records that had persisted for 14 to 154 years [2]. The event occurred during a holiday weekend when millions were outdoors, indicating a sustained atmospheric pattern rather than a transient spike. Given this historical precedent, the 0% probability for lower ranges aligns with the documented intensity of the recent July heat, framing the current pricing as a rational reflection of extreme weather continuity.

Traders should monitor the Wunderground daily history for KLGA as the official resolution source, specifically checking for any data anomalies or station recalibrations before the 2026-07-20T12:00:00Z settlement window closes. While weather lacks direct crypto macro tie-ins like BTC funding rates, on-chain mechanics for USDC settlement remain standard, with no whale flow dependencies affecting the contract outcome. The primary catalyst remains the actual meteorological reading, which will be verified against the Wunderground archive to determine the final temperature range [1].

Sources: 1 · 2

Methodology

This page reads Highest temperature in NYC on July 20? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed alongside for venue context. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

How does UMA secure the resolution?

The UMA Optimistic Oracle uses a bond system: a proposer posts a bond, a two-hour challenge window opens. On dispute the losing side forfeits the bond — financial incentive for honest resolution.

How volatile are crypto prediction markets?

Crypto markets react to spot prices — a 5% BTC move typically shifts a "BTC above X by date" market 10-20%. Polymarket crypto market liquidity is usually six-figure USD, sufficient for active trading.