Highest temperature in Houston on August 9?

Platform comparison

Market context

Houston’s maximum on 9 August at Hobby Airport is the key number here, and the market is not about the headline “high” shown in a weather app summary if that conflicts with the Daily Observations table. The crowd price at 0% YES implies the contract is either mispriced or simply illiquid, because late-summer Houston commonly sits in the low-to-mid 90s Fahrenheit and AccuWeather’s August outlook has daily highs mostly between 90°F and 97°F, with the National Weather Service also showing a 92°F daytime high for Houston that day.[1][8]

On comparable Houston August days, the outcome usually hinges on whether the airport station briefly reaches one temperature band above forecast, rather than on the night-time low or the “feels like” figure. Hobby Airport’s climate normals put the record maximum for early August at 105°F, underlining that a move into the upper 90s is entirely plausible even when forecasts look restrained.[11] On platforms, Polymarket-style contracts often display an implied probability directly, whereas Kalshi, Betfair and Smarkets may present decimal odds or back/lay prices; the same temperature range can therefore look different after spread and commission. Betfair and Smarkets also tend to be more sensitive to fees and available liquidity, while KYC access can vary by jurisdiction, so a 0% reading on one venue need not mean the event is impossible.

For traders, the main catalysts are the official updates from the Houston/Galveston NWS office and the airport METARs feeding the Hobby Airport observation record, especially if cloud cover, thunderstorms or a late-afternoon surge in heat index alter the actual peak temperature.[7][8] Weather Underground resolution will depend on the observed Daily Observations entry for the station, so a difference of even one degree can move settlement into an adjacent band if the market’s ranges are tight.[18]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Houston on August 9? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi Alternative, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Kalshi Alternative has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.