Tokyo Minimum Temperature on May 13: Will 16°C Hold?

Tokyo’s overnight temperature on May 13 has become a surprisingly active prediction market. The 16°C outcome carries a 66% implied probability, and that number jumped roughly 24.5% in the past 24 hours. That kind of single-day repricing on a short-range weather contract means new forecast data came in and traders responded fast.

The market resolves at 2026-05-13 12:00:00, which is essentially hours away. Japan Meteorological Agency forecast models for the Kanto region have been tightening around the mid-teens range for overnight lows in Tokyo. The market is pricing uncertainty, not science, but right now the forecast and the contract price are pointing in the same direction.

How the Tokyo Minimum Temperature Contract Works

This contract resolves to whichever temperature bracket matches Tokyo’s recorded minimum on May 13. The Japan Meteorological Agency maintains the official temperature record for the Tokyo Metropolitan Observatory. A YES on 16°C pays out if the official low lands in that bracket. Eleven outcome brackets span from 12°C or below up to 22°C or higher, so capital is distributed across a wide range.

• 16°C (YES): 0.66 implied probability, priced at $0.66
• 15°C: competing bracket, lower implied probability
• 17°C: adjacent bracket above
• 14°C and below brackets: lower probability outcomes
• 18°C and above brackets: lower probability outcomes

The adjacent brackets, 15°C and 17°C, are the real risk here. Tokyo’s minimum temperature in mid-May is sensitive to cloud cover, humidity, and the timing of any frontal system passing through the Kanto Plain. A 1°C shift in the overnight low is entirely plausible. The Japan Meteorological Agency forecast pins the low near 16°C, but operational forecast error at this range is typically plus or minus 1 to 2 degrees Celsius. That error window is exactly the spread between the leading bracket and its neighbors.

Sponsored Partner

A Sharp 24-Hour Move Signals New Forecast Data

The momentum composite here is worth unpacking. The 1-hour change is flat at 0.0%, but the 24-hour change is plus 24.5%, and the trend score sits at 59.56. That pattern, a sharp daily move followed by a plateau, typically means a forecast update repriced the contract and traders are now holding to see if the next model run confirms the signal.

Total market volume is $5,598, with $5,051 of that trading in the past 24 hours. Liquidity sits at $3,147. This is a thin market. Volume well below $1 million means a single large position can move the price materially. The current 66% probability reflects genuine forecast-driven conviction, but it can shift sharply if the Japan Meteorological Agency issues an updated advisory or if the next model run moves the projected low toward 15°C or 17°C.

• 24-hour momentum at plus 24.5% aligns with a Japan Meteorological Agency forecast update tightening the overnight low estimate around 16°C.
• Flat 1-hour movement suggests the market has absorbed the new data and is waiting for the next model run or the actual observation.
• Thin liquidity at $3,147 means price discovery is fragile. Any updated forecast or early observational data from Tokyo could reprice quickly.
• The trend score of 59.56 sits in moderate conviction territory, not overwhelming certainty.
• Open interest at $0 is a notable flag. Capital is moving through this market, not sitting in it.

Lines Analysis: What the Forecast Data Actually Says

Japan Meteorological Agency 5-day forecasts for the Tokyo region in mid-May 2026 have been consistent around the mid-teens for overnight lows. Seasonal climatology supports this range. Tokyo’s average minimum temperature in mid-May sits between 14°C and 17°C, with 15°C and 16°C being the most common outcomes historically. The 16°C bracket is not a long shot. It sits squarely in the climatological center of the distribution for this time of year.

The genuine risk is a frontal passage or an anomalous warm air mass. If a low-pressure system moves through the Kanto Plain overnight on May 12 to 13 and pulls warmer, moister air northward, the minimum could land at 17°C or 18°C instead. Conversely, clear skies and northwest winds after a frontal passage could push the low toward 14°C or 15°C. The Japan Meteorological Agency operational model is the single most important input here. Any revision to the overnight low forecast is the event that moves this market.

The data doesn’t care about the politics, and in this case there is no politics. This is a pure short-range forecast market. The Japan Meteorological Agency forecast favors the 16°C bracket. The 24-hour price move confirms traders read the same signal. The $5,598 total volume is thin, but the directional lean is clear.

LINES VERDICT

Forecast Aligned, Thin Market

The Japan Meteorological Agency forecast and the 24-hour price movement are pointing at the same bracket. The 16°C outcome is the climatological and forecast-supported center of the distribution for a Tokyo overnight low in mid-May.

What the market says: At 66%, traders have priced 16°C as the single most likely outcome but left meaningful probability on adjacent brackets. With resolution at 2026-05-13 12:00:00 less than 24 hours away, volatility is concentrated entirely in forecast model updates.

Key unknown: The next Japan Meteorological Agency model run for overnight May 12 to 13 in Tokyo. Any shift in the projected low toward 15°C or 17°C would reprice the 16°C bracket sharply given how thin the liquidity is.

Scientific Context: Tokyo Temperature Climatology in Mid-May

Tokyo’s climate in mid-May sits in a transitional zone between the cool spring pattern and the onset of the rainy season, known locally as tsuyu, which typically begins in early June. The Japan Meteorological Agency records show that May minimum temperatures at the Tokyo Metropolitan Observatory have been trending upward over the past two decades, consistent with urban heat island intensification and broader regional warming. The climatological average minimum for May 13 falls in the 14°C to 16°C range depending on the reference period used. The current market pricing of 66% for the 16°C bracket reflects that the upper end of the normal range is now the expected outcome, which is itself a mild signal of how Tokyo’s baseline has shifted. Any event before 2026-05-13 12:00:00 that would move this price is simple: a revised Japan Meteorological Agency forecast or an early automated weather station reading from Tokyo showing a departure from the projected low.

FAQ

• What does 66% probability mean here? It means traders collectively estimate a roughly two-in-three chance that Tokyo’s official minimum temperature on May 13 lands in the 16°C bracket, as recorded by the Japan Meteorological Agency.
• What happens to the other brackets? Every bracket except the one matching the Japan Meteorological Agency official reading resolves to zero. Capital in 15°C, 17°C, and all other brackets pays nothing if the official low is 16°C.
• What data would move the 16°C price? A Japan Meteorological Agency forecast revision shifting the projected overnight low toward 15°C or 17°C would reprice this contract immediately, especially given the thin $3,147 liquidity pool.
• When does this market resolve? Resolution is at 2026-05-13 12:00:00. The Japan Meteorological Agency official minimum temperature observation for May 13 determines the outcome.
• Is the $5,598 volume reliable for price discovery? Volume this thin means prices can move sharply on a single trade. The 66% probability reflects current trader consensus, but low liquidity makes this estimate less stable than a high-volume market.

This analysis reflects market conditions as of 2026-05-12 10:12:53. Prediction market probabilities are volatile and shift as new data and regulatory decisions emerge, especially as the 2026-05-13 12:00:00 resolution date approaches. Lines.com does not accept bets or provide financial or gambling advice. All market outcomes are uncertain.