Climate Overview
The climate in Castanhal is hot. The average annual temperature is 27°C and approximately 2539mm of precipitation falls per year. Castanhal receives a notable amount of rainfall throughout the year, including during its driest month. Castanhal sits near the equator, so seasonal temperature differences are minimal throughout the year.
Temperature
Castanhal has relatively stable temperatures year-round, staying within a 10°C range. The warmest month is October, when average highs reach 33°C and the mean temperature sits around 28°C. July is the coolest month, with minimum temperatures around 23°C and an average of 27°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows.
Precipitation
Castanhal is a very wet location, receiving approximately 2539mm of precipitation annually, which averages out to around 212mm per month. The wettest month is February, averaging 487mm of rainfall. March and April also tend to see above-average precipitation. The driest month is October, with just 36mm. That's 451mm 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
Castanhal is relatively calm, with an average annual wind speed of 2km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is October, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in April, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.
Seasons
92 days until Spring
It is currently winter in Castanhal, which began on June 21, 2026. Castanhal sits near the equator, so the traditional four-season cycle is less pronounced — temperatures remain relatively stable year-round. The warmest period peaks in October at around 33°C, while the coldest stretch bottoms out in July near 23°C. Spring is next, beginning on September 23, 2026 — 92 days from now.
Spring
Temperatures range from 23 to 33°C. Rainfall is relatively light, with around 143mm over the season and a monthly average of 48mm. Winds are generally light, averaging 3km/h. Light layers work well as temperatures warm through the season — a great time to be outdoors.
Summer
Temperatures range from 23 to 32°C. Rainfall is heavy, totalling around 955mm across the season with a monthly average of 318mm. Winds are generally light, averaging 2km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 23 to 31°C. Rainfall is heavy, totalling around 1178mm across the season with a monthly average of 393mm. Winds are generally light, averaging 2km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 23 to 32°C. Precipitation is moderate at around 264mm for the season, averaging 88mm per month. Winds are generally light, averaging 2km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Monthly Climate Data
The table below shows monthly climate averages for Castanhal 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.
