Climate Insights for Castelo

The climate in Castelo is warm and mild. The average annual temperature is 23°C and approximately 1035mm of precipitation falls per year. December is the wettest month, receiving around 190mm of rainfall. Castelo is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: January, February, March. The coldest months are July, August, June, when temperatures can drop to 14°C.

Castelo sees moderate temperature variation throughout the year, ranging from 14°C to 32°C. The warmest month is January, when average highs reach 32°C and the mean temperature sits around 26°C. July is the coolest month, with minimum temperatures around 14°C and an average of 20°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between August and September, with a 2°C shift in average temperatures.

Castelo is a moderately rainy area, receiving approximately 1035mm of precipitation annually, which averages out to around 86mm per month. The wettest month is December, averaging 190mm of rainfall. November and February also tend to see above-average precipitation. The driest month is July, with just 18mm. That's 172mm less than December, 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.

Castelo is relatively calm, with an average annual wind speed of 10km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is September, averaging 11km/h, though still comfortable for most outdoor activities. The calmest conditions occur in June, with average winds dropping to 9km/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.

It is currently autumn in Castelo, which began on March 20, 2026. Castelo is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in January at around 32°C, while the coldest stretch bottoms out in July near 14°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Castelo is during April, May, June, July, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 21°C with modest rainfall averaging 37mm per month. By contrast, January can be uncomfortably hot with temperatures reaching 32°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.

The table below shows monthly climate averages for Castelo 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.