Climate Overview
The climate in Grajaú is hot. The average annual temperature is 27°C and approximately 1011mm of precipitation falls per year. March is the wettest month, receiving around 210mm of rainfall. Grajaú sits near the equator, so seasonal temperature differences are minimal throughout the year.
Temperature
Grajaú sees moderate temperature variation throughout the year, ranging from 21°C to 36°C. September is the hottest month, with daytime highs reaching 36°C and an average of 29°C. July is the coolest month, with minimum temperatures around 21°C and an average of 27°C. On average, daily temperatures fluctuate by about 10°C between overnight lows and afternoon highs.
Precipitation
Grajaú is a moderately rainy area, receiving approximately 1011mm of precipitation annually, which averages out to around 84mm per month. The wettest month is March, averaging 210mm of rainfall. January and February also tend to see above-average precipitation. The driest month is August, with just 3mm. That's 208mm less than March, 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
Grajaú 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 July, averaging 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in March, 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
93 days until Spring
It is currently winter in Grajaú, which began on June 21, 2026. Grajaú sits near the equator, so the traditional four-season cycle is less pronounced — temperatures remain relatively stable year-round. The warmest period peaks in September at around 36°C, while the coldest stretch bottoms out in July near 21°C. Spring is next, beginning on September 23, 2026 — 93 days from now.
Spring
Temperatures range from 23 to 36°C. Rainfall is relatively light, with around 115mm over the season and a monthly average of 38mm. Winds are generally light, averaging 2km/h. Light layers work well as temperatures warm through the season — a great time to be outdoors.
Summer
Temperatures range from 23 to 33°C. Rainfall is heavy, totalling around 487mm across the season with a monthly average of 162mm. Winds are generally light, averaging 2km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 23 to 32°C. Rainfall is heavy, totalling around 397mm across the season with a monthly average of 132mm. Winds are generally light, averaging 2km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 21 to 35°C. Precipitation is minimal, with only around 13mm for the entire season. Winds are generally light, averaging 3km/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 Grajaú 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.
