Highest temperature in NYC on July 4?

Platform comparison

Market context

On 4 July 2026, LaGuardia Airport in Queens is set to record its peak daytime temperature, a real-world event that will determine the outcome of a prediction market on NYC’s highest heat. The crowd currently implies a 0% chance of any temperature exceeding 98°F, yet historical data from this week shows LaGuardia hit 104°F on 2 July 2026, shattering the 1966 record of 101°F and coming within three degrees of the all-time high of 107°F[3][7]. Just days prior, the airport also recorded its warmest midnight ever at 94°F, breaking a 2013 record and confirming an intense, persistent heat dome over the East Coast[1][5]. This recent extremity suggests the consensus view of 0% is dangerously contrarian, with value likely sitting in the 98–99°F range, which Polymarket traders already price at 41%[2].

Traders must monitor the National Weather Service’s daily climatological updates and Wunderground’s hourly logs for LaGuardia, as the market resolves on the highest temperature recorded at any time on 4 July[4]. The primary catalyst is the continuation of the current heat dome, which has already driven NYC temperatures above Phoenix’s for the first time in recent history[3]. With July 2026 forecasts projecting daily highs between 81°F and 99°F and overnight lows up to 83°F, the window for extreme heat remains wide open[10]. Any sudden shift in wind patterns or cloud cover could alter the peak, but the prevailing trend of record-breaking heat makes the 0% implied probability appear fundamentally mispriced against the evidence of 104°F recorded just two days prior[7].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in NYC on July 4? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Who Will Win 2026, which mirrors the Polymarket order book at 0% fees.

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

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 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.