Over the past 10 years, Lisbon Marathon runners have faced temperatures ranging from 16\u00b0C (60\u00b0F) on cooler years to 23\u00b0C (74\u00b0F) in warmer editions. The median temperature of 20\u00b0C (67\u00b0F) puts this race in the challenging category for running conditions.
Wind speeds average 13 km/h during race hours, with peak gusts reaching 23 km/h in challenging years. Humidity sits around 75%, and there is a 40% chance of rain on race day.
These conditions translate to an estimated pace impact of +5.9% compared to ideal running conditions. For a 4-hour marathoner, that means roughly 14 minutes slower than a perfect-weather day.