Climate Overview
The climate in Dehiwala-Mount Lavinia is hot. The average annual temperature is 28°C and approximately 2480mm of precipitation falls per year. Dehiwala-Mount Lavinia receives a notable amount of rainfall throughout the year, including during its driest month. Dehiwala-Mount Lavinia sits near the equator, so seasonal temperature differences are minimal throughout the year.
Temperature
Dehiwala-Mount Lavinia has relatively stable temperatures year-round, staying within a 6°C range. The warmest month is February, when average highs reach 31°C and the mean temperature sits around 28°C. January is the coolest month, with minimum temperatures around 25°C and an average of 27°C. Daily temperature variation is modest, with an average difference of 3°C between highs and lows.
Precipitation
Dehiwala-Mount Lavinia is a very wet location, receiving approximately 2480mm of precipitation annually, which averages out to around 207mm per month. The wettest month is November, averaging 377mm of rainfall. May and October also tend to see above-average precipitation. The driest month is February, with just 49mm. That's 328mm less than November, 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
Dehiwala-Mount Lavinia is mildly breezy, with an average annual wind speed of 14km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is June, averaging 20km/h, though still comfortable for most outdoor activities. The calmest conditions occur in March, with average winds dropping to 8km/h, making it an ideal period for wind-sensitive activities. Wind speeds vary significantly across the year, with a 12km/h difference between the calmest and windiest months. This level of variation is worth factoring into travel plans. Wind tends to pick up during the summer months. The seasonal averages are 13km/h in winter, 12km/h in spring, 19km/h in summer, 14km/h in autumn.
Seasons
87 days until Winter
It is currently autumn in Dehiwala-Mount Lavinia, which began on September 23, 2026. Dehiwala-Mount Lavinia sits near the equator, so the traditional four-season cycle is less pronounced. Temperatures remain relatively stable year-round. The warmest period peaks in February at around 31°C, while the coldest stretch bottoms out in January near 25°C. Winter is next, beginning on December 21, 2026 (87 days from now).
Spring
Temperatures range from 26 to 31°C. Rainfall is heavy, totalling around 623mm across the season with a monthly average of 208mm. Winds are generally light, averaging 12km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 26 to 29°C. Rainfall is heavy, totalling around 619mm across the season with a monthly average of 206mm. Winds are moderate at around 19km/h. Light, breathable clothing is ideal. Perfect conditions for outdoor activities.
Autumn
Temperatures range from 25 to 29°C. Rainfall is heavy, totalling around 944mm across the season with a monthly average of 315mm. Winds are generally light, averaging 14km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 25 to 31°C. Precipitation is moderate at around 294mm for the season, averaging 98mm per month. Winds are generally light, averaging 13km/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 Dehiwala-Mount Lavinia 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.
