Climate Overview
The climate in Arroyo Grande is warm and mild. The average annual temperature is 21°C and approximately 2814mm of precipitation falls per year. Arroyo Grande receives a notable amount of rainfall throughout the year, including during its driest month. Arroyo Grande is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: May, April, July. The coldest months are February, January, December, when temperatures can drop to 14°C.
Temperature
Arroyo Grande sees moderate temperature variation throughout the year, ranging from 14°C to 29°C. The warmest month is May, when average highs reach 29°C and the mean temperature sits around 23°C. February is the coolest month, with minimum temperatures around 14°C and an average of 19°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between February and March, with a 2°C shift in average temperatures.
Precipitation
Arroyo Grande is a very wet location, receiving approximately 2814mm of precipitation annually, which averages out to around 234mm per month. The wettest month is September, averaging 378mm of rainfall. June and October also tend to see above-average precipitation. The driest month is April, with just 105mm. That's 273mm 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
Arroyo Grande is relatively calm, with an average annual wind speed of 8km/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 9km/h, though still comfortable for most outdoor activities. The calmest conditions occur in June, with average winds dropping to 7km/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 Arroyo Grande, which began on March 20, 2026. Arroyo Grande 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 29°C, while the coldest stretch bottoms out in February near 14°C. Summer is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 16 to 29°C. Rainfall is heavy, totalling around 405mm across the season with a monthly average of 135mm. Winds are generally light, averaging 9km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 18 to 27°C. Rainfall is heavy, totalling around 893mm across the season with a monthly average of 298mm. Winds are generally light, averaging 8km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 17 to 27°C. Rainfall is heavy, totalling around 983mm across the season with a monthly average of 328mm. Winds are generally light, averaging 8km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 14 to 24°C. Rainfall is heavy, totalling around 533mm across the season with a monthly average of 178mm. Winds are generally light, averaging 9km/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 Arroyo Grande 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.
