TOTAL VOLUME:
$134.2b
24H VOL:
$134,145,987
24H TRANSACTIONS:
2,388,728,490
OPEN INTEREST:
$1,441,166,947
406,422
Markets across
30,383
events
MATCHED EVENTS:
2,688
PLATFORM COVERAGE:
5
Polymarket:
39%
VS.
Kalshi:
61%
Closed: May 30, 8:00 PM EST
Polymarket
This market tracks whether London will receive between 5–10mm of total precipitation during May 2026, measured at Heathrow Airport. On Polymarket, the leading outcome currently stands at 39.3%, while the scenario of 10–15mm of precipitation holds 38.0% probability. Resolution will be determined by the Met Office's official precipitation data for May 2026 from the Heathrow station, with precision to one decimal place. Watch for the Met Office's release of the Provisional figure for May 2026, expected by the end of the month, which will serve as the definitive resolution source.
Prediction market odds on Polymarket reflect trader consensus on London's May precipitation, often incorporating meteorological models and historical climate data faster than traditional analyst forecasts. While weather analysts typically issue seasonal outlooks months in advance, prediction markets update dynamically as new data arrives. The current market pricing suggests traders are weighing multiple precipitation scenarios. Comparing market odds to UK Met Office seasonal forecasts or long-range climate models can reveal whether traders are pricing in more or less precipitation risk than official forecasters expect. This divergence often highlights where new information or uncertainty is concentrated.
The Precipitation in London in May market resolves on May 31, 2026. Resolution is determined by official precipitation measurements recorded for London during the month of May. The specific outcome that resolves to yes depends on which precipitation band is confirmed by authoritative weather data. Traders should monitor the event's resolution criteria carefully, as the exact measurement source and methodology will determine which contract settles to one and which to zero. Early resolution is possible if precipitation data becomes conclusive before the end date.
Several factors could shift odds for Precipitation in London in May. Updated seasonal forecasts from the UK Met Office or European weather models may signal wetter or drier conditions ahead. El Niño or La Niña patterns, Atlantic storm tracks, and jet stream positioning all influence May rainfall over the UK. Real-time weather developments in April and early May will anchor trader expectations as the resolution date approaches. Historical precipitation patterns and climate anomalies may also prompt repricing. As May progresses and actual rainfall accumulates, market prices will converge toward the observed outcome, with late-month data driving final positioning before May 31, 2026.