Highest temperature in Seattle on July 16?

Platform comparison

Market context

Seattle-Tacoma International Airport is expected to record its peak daily temperature on 16 July 2026, a metric that will settle the prediction market currently showing a 0% implied probability for any outcome above the lowest range. Historical July data for the region indicates daytime highs typically reach 24°C to 26°C (75°F to 79°F), with the airport station often mirroring these city-wide averages despite its slightly cooler maritime influence [2][3]. The crowd’s current pricing, which heavily favours the 64–65°F range at 68% probability, suggests traders are anticipating a notably cooler day than the seasonal average, potentially influenced by recent marine layer persistence or cloud cover forecasts [1].

Traders monitoring this event should watch real-time updates from Wunderground, the designated resolution source, as the market resolves based on the highest temperature recorded for all times on the day [1]. Unlike Kalshi, which uses decimal odds and strict KYC, platforms like Polymarket operate with implied probabilities and lighter identity checks, creating divergent liquidity dynamics for weather events [1]. While Betfair and Smarkets offer decimal pricing that simplifies odds calculation for UK traders, Polymarket’s probability-based interface may obscure the true risk-reward ratio for those comparing books, particularly when the frontrunner outcome sits at 68% rather than a clear decimal price [1]. No specific weather announcements are scheduled, but the dependency on hourly Wunderground data means the settlement will hinge entirely on the final 12:00 UTC timestamp.

Sources: 1 · 2 · 3

Methodology

This page compares Highest temperature in Seattle on July 16? 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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

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.

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.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.