Polymarket weather markets: a complete guide for traders

What weather markets are

Polymarket lists daily contracts on weather thresholds across major cities: "Will the daily-high in NYC reach 28°C today?", "Will Tokyo's low go below 5°C?", etc. Resolution is mechanical — the contract reads the official station record and pays out YES or NO.

How they resolve

The market specifies a station (LaGuardia for NYC, Heathrow for London, etc.) and a threshold. At a fixed time (usually local midnight), the daily-high or daily-low is read from the station's public record. Above threshold = YES. Below = NO. Simple.

Where the edges live

• Forecast-to-reality lag:by 11 a.m., the running max-so-far is public; the market often hasn't fully repriced.
• Bias correction: raw GFS systematically overshoots in some cities and undershoots in others. We fit per-city corrections from years of residuals.
• Ensemble disagreement: when ECMWF and GFS disagree by more than 2°C, probability dispersion is high and casual bettors price the spread badly.

What you need to trade them

• Real-time station feed (ICAO-coded, 5-minute cadence).
• Multi-model ensemble forecast (ECMWF, GFS, ICON, JMA, UKMO).
• A per-city bias correction.
• A threshold-integration step that maps forecast distribution → probability.

We package all four behind one API. Pick a city from our markets index to see what each endpoint returns.

What you don't need

You don't need to build a meteorology team. You don't need to buy ECMWF forecasts at €4,500/year. You don't need to write your own bias correction. You need to know which markets are mispriced, when, and by how much.