Climate Overview
The climate in San Juan Opico is hot. The average annual temperature is 25°C and approximately 1781mm of precipitation falls per year. June is the wettest month, receiving around 347mm of rainfall. San Juan Opico is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: March, April, February. The coldest months are January, February, December, when temperatures can drop to 19°C.
Temperature
San Juan Opico sees moderate temperature variation throughout the year, ranging from 19°C to 33°C. The warmest month is March, when average highs reach 33°C and the mean temperature sits around 26°C. January is the coolest month, with minimum temperatures around 19°C and an average of 24°C. On average, daily temperatures fluctuate by about 10°C between overnight lows and afternoon highs.
Precipitation
San Juan Opico is a fairly wet location, receiving approximately 1781mm of precipitation annually, which averages out to around 148mm per month. The wettest month is June, averaging 347mm of rainfall. September and October also tend to see above-average precipitation. The driest month is February, with just 2mm. That's 345mm less than June, 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
San Juan Opico is relatively calm, with an average annual wind speed of 11km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 14km/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. There is moderate seasonal variation in wind speed, with a 6km/h gap between the calmest and windiest months. Wind tends to be stronger during winter months, driven by seasonal pressure systems. The seasonal averages break down to 14km/h in winter, 11km/h in spring, 8km/h in summer, 9km/h in autumn.
Seasons
89 days until Summer
It is currently spring in San Juan Opico, which began on March 20, 2026. San Juan Opico 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 March at around 33°C, while the coldest stretch bottoms out in January near 19°C. Summer is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 20 to 33°C. Rainfall is heavy, totalling around 308mm across the season with a monthly average of 103mm. Winds are generally light, averaging 11km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 21 to 31°C. Rainfall is heavy, totalling around 775mm across the season with a monthly average of 258mm. Winds are generally light, averaging 8km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 20 to 30°C. Rainfall is heavy, totalling around 685mm across the season with a monthly average of 228mm. Winds are generally light, averaging 9km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 19 to 32°C. Precipitation is minimal, with only around 13mm for the entire season. Winds are generally light, averaging 14km/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 San Juan Opico is during January, February, November and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 24°C with modest rainfall averaging 24mm per month. By contrast, March can be uncomfortably hot with temperatures reaching 33°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.
Monthly Climate Data
The table below shows monthly climate averages for San Juan Opico 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.
