Denver's weather on May 19 is predicted through this narrow 66-67°F range market, which expires at the close of that date. At 2% odds for YES, traders are expressing strong skepticism that the day's high temperature will land in this precise band. This represents only a 1-degree Fahrenheit window—a notably tight constraint in daily weather forecasting, where even the most accurate meteorological models carry uncertainty bands of several degrees. Spring weather in Denver typically brings highly variable conditions with daily highs ranging anywhere from the low 60s to low 70s Fahrenheit, depending on weather systems moving across the region. A 66-67°F peak suggests cool weather, potentially linked to persistent cloud cover, precipitation events, or an organized cool front moving through the area. The market's 2% valuation reflects the inherent difficulty of predicting such a narrow temperature range; even experienced forecasters maintain wide confidence intervals around specific daily high temperatures. The current price implies traders expect the actual May 19 maximum to either fall below 66°F or exceed 67°F by a meaningful margin.
Deep dive — what moves this market
Denver's high-altitude climate and semi-arid continental weather patterns create unique forecasting challenges that complicate predicting any single day's peak temperature. The city sits at 5,280 feet elevation where rapid daytime solar heating can produce temperature swings of 20-30 degrees Fahrenheit between daily highs and lows, even during late May when the season transitions toward summer. The 66-67°F target represents a notably cool peak—roughly 10-15 degrees below Denver's May statistical average high temperature of around 76-78 degrees Fahrenheit. For this narrow range to occur on May 19, several weather conditions would need to align with precision: either a strong Pacific cool front would need to move through the region, sustaining significant cloud cover throughout daylight hours and actively suppressing solar heating, or an organized weather system would need to bring rain or light snow at elevation while limiting afternoon warming potential. The absence of strong upper-atmospheric dynamics or organized frontal systems in extended-range forecasts as of mid-May makes traders collectively skeptical of this outcome materializing. Conversely, factors that could push toward YES include an unexpected early-season cold pattern propagating from Canada, high-altitude moisture transport from the Pacific, or a cut-off low-pressure system stalling near the region. Historical weather records suggest that 66-67°F highs in Denver are far more common in April or early June than in mid-May; during May's meteorological transition period, steady warming and pressure from higher sun angles typically dominate the weather pattern. The 2% odds assignment reflects market participants' collective judgment that mainstream numerical weather models do not support a cool-suppressed day; traders are effectively pricing in roughly 98% confidence that Denver's peak will fall outside this band. This conviction level represents extraordinarily high certainty for a weather-dependent market, even accounting for the narrow range constraint inherent in the question. Recent spring weather patterns across the High Plains have trended warmer than normal, further supporting trader skepticism about a late May cool-down. The market resolution will depend entirely on official National Weather Service Denver-Boulder data recorded at the official observation station; no subjective interpretation or outside data applies.
What traders watch for
May 19 high temperature data from National Weather Service Denver-Boulder station determines the outcome; official records finalize at market expiration.
Extended-range weather forecasts through May 18-19 will be monitored by traders; any hint of a cool front could shift market pricing.
Upper-atmosphere pressure patterns and jet stream positioning in the 48-72 hours before May 19 will influence whether cool air advects to the region.
Historical temperature data shows 66-67°F highs are rare in Denver during May; comparison to climate records informs trader conviction levels.
How does this market resolve?
The market resolves YES if the National Weather Service Denver-Boulder official station records a maximum temperature between 66-67°F (inclusive) on May 19, 2026. Otherwise, it resolves NO.
Prediction markets aggregate trader expectations into real-time probability estimates. On Polymarket Trade, every market question resolves YES or NO based on a specific event outcome; traders buy shares of the side they believe will resolve positively. Prices range 0¢ (certain no) to 100¢ (certain yes) and naturally reflect the crowd-implied probability of YES. This page summarizes the market state for readers arriving from search; for live trading (place orders, see order book depth, execute a trade) open the full interactive page linked above.
