Highest temperature in NYC on July 5?

Platform comparison

Market context

The underlying event is the highest temperature recorded at LaGuardia Airport on 5 July 2026, a date that has already seen extreme heat in the region. Recent records show LaGuardia hitting 102°F on 4 July, with midnight temperatures reaching 94°F, the warmest ever for that time in New York City[1][5]. This sets a high baseline for the following day, suggesting that a 0% implied probability for the 84–85°F range is likely mispriced, as historical comparables indicate peak temperatures in the 90s or higher during this heat wave[1][6].

Traders should monitor real-time updates from Wunderground and NWS forecasts for Central Park, which currently project daily highs between 81°F and 99°F for July 2026 at LaGuardia[3]. The key catalyst is whether the heat wave persists into the 5th, as recent data shows both LaGuardia and Newark hitting 104°F on 4 July, with dew points returning to the 70s and heat indexes peaking[6]. Analyst consensus, reflected in the 34.5% odds for the 84–85°F range, appears thin given the volume of only $5,602 and the strength of the preceding heat event[2]. Divergence between sportsbook lines and prediction-market odds suggests the market may be underestimating the likelihood of temperatures exceeding 90°F, especially with no major cooling systems announced.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 vs Polymarket. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.