Climate Overview
The climate in Ascensión is hot. The average annual temperature is 25°C and approximately 1302mm of precipitation falls per year. February is the wettest month, receiving around 206mm of rainfall. Ascensión is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: September, October, November. The coldest months are July, June, August, when temperatures can drop to 17°C.
Temperature
Ascensión sees moderate temperature variation throughout the year, ranging from 17°C to 33°C. The warmest month is September, when average highs reach 33°C and the mean temperature sits around 27°C. July is the coolest month, with minimum temperatures around 17°C and an average of 22°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between August and September, with a 2°C shift in average temperatures.
Precipitation
Ascensión is a fairly wet location, receiving approximately 1302mm of precipitation annually, which averages out to around 108mm per month. The wettest month is February, averaging 206mm of rainfall. January and December also tend to see above-average precipitation. The driest month is July, with just 12mm. That's 194mm less than February, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Ascensión is mildly breezy, with an average annual wind speed of 12km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is August, averaging 14km/h, though still comfortable for most outdoor activities. The calmest conditions occur in March, with average winds dropping to 11km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 3km/h between the calmest and windiest months.
Seasons
89 days until Winter
It is currently autumn in Ascensión, which began on March 20, 2026. Ascensión is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in September at around 33°C, while the coldest stretch bottoms out in July near 17°C. Winter is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 21 to 33°C. Precipitation is moderate at around 300mm for the season, averaging 100mm per month. Winds are generally light, averaging 13km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 23 to 31°C. Rainfall is heavy, totalling around 611mm across the season with a monthly average of 204mm. Winds are generally light, averaging 12km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 19 to 30°C. Rainfall is heavy, totalling around 322mm across the season with a monthly average of 107mm. Winds are generally light, averaging 11km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 17 to 31°C. Rainfall is relatively light, with around 68mm over the season and a monthly average of 23mm. Winds are generally light, averaging 13km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Best Time to Visit
The best time to visit Ascensión is during May, June, July and August, when the weather is most comfortable for travellers. During these months, average temperatures hover around 23°C with modest rainfall averaging 31mm per month. By contrast, September can be uncomfortably hot with temperatures reaching 33°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.
Monthly Climate Data
The table below shows monthly climate averages for Ascensión based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
