Miami Lowest Temp May 14: Can 74-75°F Hold?

Miami’s overnight temperature on May 14 has split traders almost evenly, with the 74-75°F bracket sitting at 40.5% probability. That’s a meaningful lean, but far from settled. The market jumped 15.5% in the last 24 hours, suggesting fresh conviction entered this contract after a pattern shift in the regional forecast. With resolution arriving at noon on May 14, the window to reprice is closing fast.

Here’s what the measurements are telling us: Miami in mid-May typically posts overnight lows in the low-to-mid 70s, driven by sea surface temperatures in Biscayne Bay and the prevailing southerly flow off the Atlantic. A dry, subsiding air mass can push lows into the upper 70s. A front, even a weak one, can pull them toward 72°F or below. Right now, the 74-75°F bracket is the mode, but the spread of competing outcomes across this market tells you traders aren’t confident the mode wins.

How the Miami Overnight Low Contract Works

This contract resolves YES for the 74-75°F bracket if the official lowest temperature recorded in Miami on May 14 falls between 74°F and 75°F inclusive. The resolution source is Polymarket’s designated weather data feed. Resolution occurs at noon on May 14, 2026, based on the verified overnight low through that morning.

• 74-75°F (YES): $0.41 implied probability, 40.5% chance of resolving correct.
• 76-77°F: Competing bracket, trades separately on Polymarket.
• 72-73°F: Competing bracket for a cooler outcome.
• 78-79°F and above: Warmer brackets active in the same market structure.
• 70-71°F and below: Cooler-edge brackets with lower implied probability.

The 74-75°F bracket misses when Miami’s overnight low lands in any adjacent range. A warmer-than-expected night pushes the payout to the 76-77°F or higher brackets. A cooler night, driven by increased winds or a late-season front, shifts value to 72-73°F or below. The margin between brackets is just two degrees, so small forecast errors reprice this contract sharply.

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A Fifteen-Point Overnight Move and What It Means

The 15.5% price jump over the last 24 hours, combined with a flat one-hour reading and a trend score of 42.46, points to a single catalyst: a forecast update that improved alignment between the 74-75°F bracket and model output. That kind of move in a weather market almost always traces to a new National Weather Service forecast cycle or updated model ensemble data tightening around a specific low temperature range.

Total volume sits at $1,616, with $1,255 of that changing hands in the last 24 hours. Liquidity is $12,526. This is a thin market. At this volume level, a single mid-size trade can move the price by several percentage points. The 40.5% probability reflects genuine trader conviction, but it also reflects the fact that not many traders are in this market. Treat the price as directional, not definitive.

• The 74-75°F bracket holds the highest single-outcome probability in the market, making it the consensus mode for Miami’s May 14 overnight low.
• The 24-hour price gain of +15.5% followed forecast model updates and represents the sharpest single-day move this contract has seen based on recent price history.
• Open interest stands at zero dollars, meaning all current positions have been offset or the data feed is reflecting only unmatched orders. Monitor for a shift before resolution.
• Thin liquidity at $12,526 means any NWS forecast revision before midnight May 13 could trigger an outsized price swing in either direction.
• The one-hour flat reading suggests the market has absorbed the recent forecast update and is now in a wait-and-see posture ahead of the final observation window.

Lines Analysis: What the Miami Data Actually Supports

The National Weather Service Miami forecast office issues hourly updated guidance for the Miami International Airport station, which typically serves as the resolution anchor for weather-based contracts. Mid-May in Miami sits in the transition zone between the dry season and early wet season. The Bermuda High frequently extends westward during this period, limiting frontal penetration and keeping overnight lows in the 74-77°F corridor. That structural pattern supports the 74-75°F bracket as a reasonable modal outcome.

The case against the 74-75°F bracket centers on warm-side risk. Late spring in Miami carries genuine warm-side tail risk. If a persistent onshore southeasterly flow strengthens before May 14, overnight lows can stay elevated into the 76-78°F range. That would shift value to higher brackets. The 76-77°F bracket is the most direct competitor, and if NWS model output continues trending warmer in overnight cycles, the 40.5% probability on 74-75°F could erode quickly before resolution.

• NWS Miami’s next forecast package before midnight May 13 is the single highest-impact data release for this contract.
• GFS and Euro model ensemble overnight low output for Miami on May 14 will drive any remaining price discovery in this market.
• Sea surface temperatures in Biscayne Bay running above average would support warm-side outcomes and pressure the 74-75°F bracket downward.
• Any measurable increase in wind speed overnight from May 13 to 14 would mix the boundary layer and potentially suppress lows into the 72-73°F range.
• Convective activity along a pre-frontal trough could produce an unexpected low-side reading, repricing the cooler brackets above current probability.

The $1,616 total volume reflects a niche weather market with limited participation. The data favors the 74-75°F bracket as the modal outcome for mid-May Miami. But with two-degree resolution bands and a thin order book, the margin for a surprise is real. The market is pricing uncertainty, not science.

LINES VERDICT

Narrow Favorite, Thin Market

The 74-75°F bracket holds the strongest single-outcome position in this market, and the 24-hour price surge aligns with improving forecast support for that range. But thin liquidity and a two-degree resolution band mean this contract can reprice on a single NWS forecast update.

What the market says: 40.5% probability on the 74-75°F bracket reflects trader consensus around the modal overnight low for Miami on May 14. With resolution at noon on May 14, 2026, the remaining price discovery window is short. Thin volume means the price can move sharply if new forecast data hits before midnight.

Key unknown: The NWS Miami forecast package issued overnight on May 13 is the single most important data input. A shift in the projected overnight low of even two degrees would reprice this contract and redirect probability mass toward the 72-73°F or 76-77°F brackets.

Scientific and Meteorological Context

Miami’s May climate record shows overnight lows clustering between 72°F and 78°F during the second week of the month. The transition from the dry season toward early wet season typically happens in mid-to-late May, so May 14 sits near the edge of that shift. NOAA climate normals for Miami in mid-May show average overnight lows near 74-75°F, which is exactly the bracket the market is favoring. That alignment between normals and market pricing is notable. It suggests traders are anchoring to climatology in the absence of a strong directional signal from current models.

Before resolution at noon on May 14, the two events most likely to move price are a late-night NWS forecast revision and any observed shift in the Miami surface observation network toward a warmer or cooler overnight trend. The data doesn’t care about the politics of weather forecasting. The final observation will be what it will be.

Frequently Asked Questions

• What does 40.5% probability mean here? It means traders collectively assign a 40.5% chance that Miami’s official lowest temperature on May 14 falls between 74°F and 75°F inclusive. Every other temperature bracket shares the remaining 59.5%.
• What happens if the overnight low lands outside 74-75°F? The 74-75°F contract resolves worthless. Capital shifts to whichever bracket correctly captures the recorded low, whether that is 72-73°F, 76-77°F, or any other range.
• What data release would move this contract most? The NWS Miami overnight forecast package, typically issued between 11 PM and 1 AM local time, directly updates the projected overnight low and would reprice this market immediately.
• When does this contract resolve? Resolution occurs at noon on May 14, 2026, based on the verified overnight low temperature for Miami recorded through that morning.
• Is the volume reliable enough to trust the price? Total volume is $1,616, which is very thin. Liquidity at $12,526 means the order book has depth, but the price can move sharply on a small trade or a single forecast update before resolution.

This analysis reflects market conditions as of 2026-05-13 00:29:18. Prediction market probabilities are volatile and shift as new data and regulatory decisions emerge, especially as the 2026-05-14 12:00:00 resolution date approaches. Lines.com does not accept bets or provide financial or gambling advice. All market outcomes are uncertain.