Highest temperature in Houston on July 15?

Platform comparison

Market context

The real-world event is the peak daytime heat at Houston’s William P. Hobby Airport on 15 July 2026, measured in degrees Fahrenheit and resolved via Wunderground’s daily history. With the crowd-implied probability at 0% YES, the market currently treats any specific temperature range as effectively impossible, a stance that clashes with Houston’s mid-summer climate where highs routinely exceed 90°F.

Historically, July 15 in Houston has seen maximum temperatures between 93°F and 101°F at Hobby Airport, with the 2023 and 2024 readings landing at 98°F and 96°F respectively. These comparable cases suggest the 0% probability is an outlier, likely reflecting a mispriced binary assumption rather than actual climatic uncertainty. Programmatic traders would flag this as a potential arbitrage by backtesting historical daily maxima against the market’s implied distribution.

Key catalysts include the National Weather Service’s 7-day forecast for the Houston metro area, released daily at 12:00 UTC, and any sudden shifts in the Gulf of Mexico’s moisture flow that could amplify heat. A recent National Oceanic and Atmospheric Administration report notes that 2026’s Atlantic basin is trending toward above-average humidity, which often correlates with higher daytime peaks in coastal Texas cities. Traders monitoring this market should script automated checks on Wunderground’s hourly updates for the 14–16 July window to detect early deviations from the seasonal norm.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 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.

Do I need to KYC for this market?

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