Highest temperature in NYC on August 21?

Platform comparison

Market context

LaGuardia was running slightly cooler than a classic late-summer spike on 21 August, with recent forecasts clustering around the upper 70s to lower 80s rather than a clear push into the mid-80s. That leaves the market’s 0% yes price tied to a fairly ordinary temperature distribution: a modest daytime high, but not one that obviously threatens the higher resolution bands.

The historical frame here is straightforward. Late-August highs in New York often sit in the upper 70s or low 80s when onshore flow or cloud cover is present, while the 80s-plus outcomes usually need stronger heat and lighter winds. Recent official forecasting for the city pointed to upper 70s to lower 80s, and LaGuardia-specific market weather feeds showed highs near 78°F with clouds and a small rain chance, which is consistent with a low-ceiling temperature day rather than an extreme outlier.

For traders, the main catalysts are the hourly temperature trend, any change in cloud cover, and whether showers arrive early enough to cap the afternoon peak. Winds off the north and north-east can suppress the maximum at LaGuardia, while any late clearing would matter more for the settlement band than the morning conditions. The key check is the highest value in the Daily Observations table before the settlement window closes, because that figure, not the summary high-low line, determines the outcome.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

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UK Frequently Asked Questions

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