Highest temperature in Dallas on August 21?

Platform comparison

Market context

Dallas Love Field’s 21 August heat looks priced as a near-certainty, with the market’s crowd-implied probability at 100% YES. In handicapper terms, that leaves the favourite fully installed and the real question is only where within the listed temperature bands the day lands, not whether it clears the threshold.

The historical read is straightforward: late-August Dallas often sits in the upper 90s to low 100s, and the surrounding forecast set-up has pointed to another very hot afternoon. Current published expectations from local and national weather outlets clustered around roughly 105-106°F for the day, with midday observations already in the 90s and heat index values running above 100°F, which supports the consensus side rather than the underdog. That makes a contrarian miss only plausible if cloud cover, wind shift, or earlier-than-expected cooling caps the peak below the top band.

The catalysts to watch are the day’s actual station observations rather than the headline daily high/low summary, because this market settles on the Daily Observations table at Weather Underground. The key dependency is simply whether the final Love Field reading is logged before the settlement window closes, and whether any late updates adjust the highest recorded value. With the favourite already fully reflected in price, any value sits in the banding itself: a modestly lower peak remains the only live angle for anyone looking against the consensus.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Dallas on August 21? 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, which mirrors the Polymarket order book at 0% fees.

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.

UK Frequently Asked Questions

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.

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.

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

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