Trade: Highest temperature in Miami on May 9?

Market context

On 9 May 2026, the highest temperature recorded at Miami International Airport will fall within one of several defined ranges. The settlement will use historical weather data from Weather Underground, capturing the single highest reading across the full calendar day at this official station. The current order book on Polymarket shows 0% implied probability, indicating no traders are currently backing any specific temperature range at meaningful odds.

Miami's May weather typically ranges between 75°F and 90°F, with historical data from the National Weather Service showing average highs around 86–88°F during this period. Extreme readings above 95°F or below 75°F on any given 9 May are uncommon but not unprecedented; the station's records show occasional outliers driven by tropical systems or unusual pressure patterns. The current flat probability distribution suggests the market has not yet attracted sufficient liquidity to establish consensus around any particular range, leaving significant gaps in the order book.

Traders monitoring this market should track Atlantic hurricane season activity and upper-level atmospheric patterns as May approaches. The National Oceanic and Atmospheric Administration's seasonal forecasts and real-time weather models from the European Centre for Medium-Range Weather Forecasts will provide the most reliable guidance on whether conditions favour above-normal or below-normal temperatures. Any tropical system development in the western Atlantic could materially shift temperature expectations, though such systems remain relatively uncommon in early May compared to later summer months.

Resolution source

This market settles from the official outcome published at https://www.wunderground.com/history/daily/us/fl/miami/KMIA. A proposer submits the final result to the UMA optimistic oracle on Polygon; the two-hour dispute window closes and payouts clear in USDC.

How to trade this market step by step

The mechanics for trading "Highest temperature in Miami on May 9?" are the same as any other PolyGram event contract. Each YES share resolves to $1 if the event happens, or $0 if it doesn't. The current price between 0¢ and 100¢ is the market's probability estimate, set live by the order book.

1. Sign in on polygram.ink with your email — no full KYC under $1,500 lifetime trading volume.
2. Deposit USDC on Polygon (lowest fees, ~$0.01 per transaction) or Ethereum. Funds credit after 12 confirmations.
3. Pick a side. Buy YES if you believe the event will happen; buy NO if you think it won't. The current YES price reflects the market's collective probability.
4. Size your position. If you stake 100 USDC at 50% YES, you'll receive shares that pay $200 if YES resolves true — a 100% gross return. If NO resolves, your shares are worth $0.
5. Set risk controls (optional). Stop-loss, take-profit, and limit-order types all supported. Use the trade ticket's slippage box to cap your maximum entry price.
6. Wait for resolution. When the event resolves on-chain via the UMA optimistic oracle, the winning side settles to 100¢ automatically and USDC hits your balance within seconds. Withdrawable to any wallet you control.

How active is this market?

$72K in lifetime turnover and $0 of resting liquidity puts this market in the above the median by volume for weather contracts on PolyGram. Order-book depth is thin — large orders may need to be split across the book or executed as limit orders.

The market has been open for under a month — fresh enough that information asymmetry remains a real factor.

Higher-volume markets tend to have tighter spreads and faster price discovery — meaning the displayed YES/NO percentages are more likely to reflect the true crowd-implied probability rather than a single trader's directional view.

Key terms

YES / NO share

A binary outcome token that pays $1.00 if the underlying claim resolves true (YES) or false (NO), and $0 otherwise. The market price between 0¢ and 100¢ is the implied probability.

CLOB

Central limit order book. The matching engine that pairs YES buyers with NO buyers (effectively the same trade). Polymarket's CLOB on Polygon executes trades on-chain via the conditional-tokens framework.

Liquidity

USDC capital sitting in resting limit orders inside the order book. Deeper liquidity means smaller slippage on large trades and a tighter bid-ask spread.

UMA optimistic oracle

The on-chain dispute system that settles each Polymarket market. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution.

Slippage

The difference between the displayed mid-price and your fill price. Affects market orders most; limit orders avoid slippage but may take time to fill.

Conditional token

ERC-1155 outcome share issued by Gnosis Conditional Tokens on Polygon. The token type that resolves to $1.00 or $0.00 at settlement.

See the full prediction-market glossary →

Frequently asked questions

Risk and regulatory note

Prediction-market positions can lose 100% of staked capital. Outcomes are uncertain by definition — historical accuracy of crowd-implied probabilities is high in aggregate but not for any single market. PolyGram does not provide investment advice. Trade only with capital you can afford to lose.

Regulatory status varies by jurisdiction. Germany, the United States, and most EU countries treat Polymarket-style event contracts under one of three frameworks: financial derivative, gambling product, or unregulated novel asset. Consult local counsel before trading.

Related prediction markets

Explore more prediction market odds and trading opportunities on PolyGram:

• All weather prediction markets
• How prediction markets work
• Browse all prediction markets on PolyGram
• Top prediction market traders
• Back to PolyGram home