Climate Overview
The climate in La Unión is warm and mild. The average annual temperature is 22°C and approximately 2517mm of precipitation falls per year. La Unión receives a notable amount of rainfall throughout the year, including during its driest month. La Unión is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: May, April, June. The coldest months are January, February, December, when temperatures can drop to 17°C.
Temperature
La Unión sees moderate temperature variation throughout the year, ranging from 17°C to 30°C. The warmest month is May, when average highs reach 30°C and the mean temperature sits around 25°C. January is the coolest month, with minimum temperatures around 17°C and an average of 20°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows.
Precipitation
La Unión is a very wet location, receiving approximately 2517mm of precipitation annually, which averages out to around 210mm per month. The wettest month is September, averaging 335mm of rainfall. June and October also tend to see above-average precipitation. The driest month is April, with just 76mm. That's 259mm less than September, the wettest month. Precipitation varies noticeably between seasons, with the second half (July to December) of the year generally seeing more rainfall.
Wind
La Unión is relatively calm, with an average annual wind speed of 9km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is March, averaging 10km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 8km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 2km/h between the calmest and windiest months.
Seasons
89 days until Summer
It is currently spring in La Unión, which began on March 20, 2026. La Unión is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in May at around 30°C, while the coldest stretch bottoms out in January near 17°C. Summer is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 18 to 30°C. Rainfall is heavy, totalling around 353mm across the season with a monthly average of 118mm. Winds are generally light, averaging 10km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 20 to 29°C. Rainfall is heavy, totalling around 898mm across the season with a monthly average of 299mm. Winds are generally light, averaging 9km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 19 to 29°C. Rainfall is heavy, totalling around 904mm across the season with a monthly average of 301mm. Winds are generally light, averaging 8km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 17 to 25°C. Rainfall is heavy, totalling around 362mm across the season with a monthly average of 121mm. Winds are generally light, averaging 9km/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 La Unión is during February, March and April, when the weather is most comfortable for travellers. During these months, average temperatures hover around 22°C with modest rainfall averaging 88mm per month. By contrast, May can be uncomfortably hot with highs reaching 30°C, while January is the coldest period with lows dropping to 17°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.
Monthly Climate Data
The table below shows monthly climate averages for La Unión 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.
