Highest temperature in Miami on August 6?

Platform comparison

Market context

The last 24–48 hours of pricing have kept the market anchored around a sub-90°F outcome, with the crowd currently splitting most of its weight between **88–89°F** and **86–87°F**, while **0% YES** suggests no meaningful bid for a hotter-than-expected spike. That is consistent with the latest Miami guidance pointing to daily highs in the high 80s, and with the event being resolved from the **Wunderground Daily Observations** at Miami International Airport rather than a headline summary number.[1][2]

In comparable late-summer Miami cases, the main swing factor is usually not background heat, but whether afternoon shower or thunderstorm coverage trims the top reading before the first observation after midnight locks the result. August norms in Miami are still hot, but the distribution tends to cluster tightly; recent historical and forecast data both point to highs around the upper 80s to low 90s, which leaves the market’s current centre of gravity near 88°F looking more defensible than a leap into the 90s.[1][3][10]

For traders, the key watchpoint is the day’s observation sequence at KMIA: if early afternoon temperatures top out before convective cloud and rain build, the upper end of the range becomes more plausible; if showers arrive earlier, the settlement range can stay lower. The market description also notes that revisions to recorded temperatures remain relevant until the first datapoint for the following date is published, so late database updates on Wunderground can still matter after the day ends.[2]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Miami on August 6? 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.

UK Frequently Asked Questions

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.