An integrated analysis based on 46 years of ERA5 data reveals that COP31's November 9–20 window falls within the riskiest 39% of the year. In Antalya, November coincides with the Mediterranean climate's transition into the rainy season — an average of 44.5 mm of cumulative rainfall, an 11% chance of extreme rainfall exceeding 100 mm, and some of the year's strongest wind gusts all occur during this period. The second half of the window in particular (November 14–20) is markedly riskier — the daily risk score climbs sharply from November 17 onward (0.38 → 0.62). Under climate-change scenarios, the tendency for autumn rainfall in the Mediterranean to fall less frequently but more intensely reinforces this window's "mostly dry but prone to surprise severe events" character.
| Window | Avg Rain | P90 Rain | >100mm Prob. | Avg Max Gust | >20m/s Prob. | Temp | Risk Score |
|---|
In Antalya, November marks the Mediterranean climate's entry into the rainy season. Between the year's lowest-risk period (June–September, risk score 0.01–0.12) and its highest-risk period (December–January, risk score 0.75–0.87), November acts as a "rapid transition zone." The difference in risk between the first and last week of November is enormous: a risk score of 0.38 on November 9 jumps to 0.72 toward November 30. COP31 sits right at this threshold.
From November 9–20, the average temperature is 14.2°C and the average minimum temperature is 6.8°C. While this is a "cool but comfortable" range for conference attendees, in 5 of the 46 years (11%) the in-window minimum temperature dropped below 3°C. Once wind-chill is factored in, outdoor events can become uncomfortable. For comparison: the average temperature is 21°C in mid-May and 19°C in early October — both more comfortable and lower-risk.
During the COP period, the average 10m wind speed appears quite calm at ~1.5 m/s, yet gust values can reach 10× that. This reflects the "sudden storm in still air" pattern typical of the Mediterranean. Because the mean wind is low, wind-energy potential is limited, but gusts pose a serious threat to structural safety and outdoor events. In 11% of the 46 years, gusts above 20 m/s (72 km/h) were recorded — a level that marks the damage threshold for temporary structures.
The data show that the mid-May – early-June and late-September – early-October windows are far more suitable for COP31. Mid-May: average rainfall 25 mm (half of COP's), gust 11.8 m/s (19% below COP's), temperature 21°C, >100mm probability 3% (a quarter of COP's). Late September: rainfall 16 mm, gust 12 m/s, temperature 24°C, severe-event probability near zero. Both windows are viable for Antalya in terms of the diplomatic calendar, accommodation capacity, and flight connections.
Holding COP31 in mid-November in Antalya carries an "irony risk": a summit convened to discuss climate change being struck by a climate-driven disaster itself. The 46-year data show an 11% probability of 100mm+ rainfall (flood risk), an 11% probability of a 20m/s+ storm, and an 11% probability of both heavy rain and strong wind on the same day. These are not low probabilities — they occur roughly 1 year in 9. Given the tendency for extreme events to intensify under climate change, the actual probability may be higher than the historical average. Operationally: emergency planning, backup indoor capacity, stormwater drainage infrastructure, and early-warning systems are essential.
This page is an integrated meteorological risk assessment for the 9–20 November 2026 window, when the COP31 climate summit is scheduled to be held in Antalya, built from 46 years of ERA5 reanalysis data (1980–2025, over 404,000 hourly observations). The analysis compares rainfall, wind gust, mean wind and temperature statistics across 12-day rolling windows through the year to place mid-November's risk profile in context and to surface lower-risk alternative date windows.
The calculations and charts on this page are produced with Alkazar's UrClimate climate-risk analytics methodology, the same approach used in our project-level meteorological risk and climate-data services.
The explanation on this page is for general information and does not replace project-specific engineering services. Final values should be determined under the currently applicable edition of the relevant standard.