Highest temperature in Miami on August 13?

Platform comparison

Market context

Miami International Airport will record its highest temperature on 13 August 2026, with traders currently assigning zero probability to any outcome occurring. The market resolves based on Weather Underground's Daily Observations table rather than summary figures, establishing a precise measurement standard that eliminates ambiguity between different reporting methodologies.

August temperatures in Miami exhibit minimal variance year-on-year, with historical records showing the daily high typically ranges between 89–92°F during this period. The National Weather Service reports that Miami's August average high stands at 90°F, with extreme outliers rare; the city has recorded only three days exceeding 95°F in August across the past two decades. This consistency explains why prediction markets and traditional weather forecasting services converge on narrow probability distributions for specific temperature brackets. The zero crowd probability reflects confidence that the actual reading will fall within a predictable band rather than uncertainty about whether measurement will occur.

The primary catalyst affecting August 2026 temperatures will be Atlantic hurricane activity and tropical moisture patterns, which typically intensify during peak season. The National Oceanic and Atmospheric Administration's seasonal outlook, released in May 2026, will provide initial guidance on whether above-normal or below-normal conditions are expected. Any significant tropical system affecting South Florida in early August could suppress daytime highs through cloud cover and precipitation, whilst an extended high-pressure system could elevate readings toward the upper boundary of historical norms. Real-time atmospheric monitoring from mid-July onwards will sharpen forecasts considerably closer to the settlement date.

Methodology

We track Highest temperature in Miami on August 13? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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.